JP2010112963A - Preloaded microscale device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein in a microfluidic device a bed is preferably preserved or transported in a dried state, but the bed may become malfunctioned depending on the drying, maintenance, transformation, or reconstruction. <P>SOLUTION: A microfluidic device comprising one, two or more micro-channel structures 101, each of which comprises a reaction micro-reaction spaces (104a-104h) for retaining a solid phase material in the form of a wet porous bed. Each of one, two or more micro-channel structures 101 includes the solid phase material in a dry state together with a bed-preserving agent comprising one or more compounds having bed-preserving activity. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a microfluidic device for carrying out experiments, each comprising an interaction between a solid phase material (= support material) and a solute (S or S ′) present in a liquid. device). The solid phase material is present in the device as a porous bed during the experiment. The device allows one or more experiments to be performed in parallel within the device.

  Parallelism means that at least the interaction between the solute and the solid phase material occurs in parallel for two or more experiments. The reagents / reactants used can vary.

  The term “solute” refers to true solutes, viruses containing microorganisms, suspended cells, suspended cell parts and lysed or colloidal forms, which are referred to herein as a liquid flow through a porous bed. Including various other reactants that are small enough to be transported by

The term “microfluidic device” refers to one or more devices in which a stream is used to transport various types of reactants, analytes, products, samples, buffers, etc. This means that the microchannel structure is provided. The term “micro” in “microchannel structure” means one or more cavities having a cross-sectional area dimension of ≦ 10 ³ μm, preferably ≦ 5 × 10 ² μm, for example ≦ 10 ² μm and Intended to have a conduit. The device is capable of processing liquid aliquots in the nanoliter (nl) range (including the picoliter (pl) range). The nl range has an upper end of 5,000 nl, but in most cases relates to a volume of ≦ 1,000 nl, for example ≦ 500 nl or ≦ 100 nl.

The interaction between the solute and the porous bed is, for example,
a) Separation of the solute from the liquid, i.e. the solute is retained on the solid phase material with the result that the porous bed plus solute can be separated from the liquid,
b) catalytic reactions, eg interactions as part of an enzymatic reaction,
c) intended for solid phase synthesis and / or d) solid phase derivatization.
Patent publications (WO and US applications and issued US patents) cited herein are hereby incorporated by reference in their entirety.

Background publication WO 02075312 (Gyros AB) focuses on affinity assays for characterizing reaction variables by binding soluble reactants to a solid phase material, including an immobilized counterpart to the affinity reactant. I guess. The solid phase is represented by a porous bed placed either by the inner wall of the reaction microcavity or in the microreaction space.

  WO 03093802 (Gyros AB) describes performing a catalytic assay on one part of the catalyst system used in immobilized form. The assay is exemplified by an enzyme system. Immobilization techniques and solid phase materials are basically the same as in WO 02075312 (Gyros AB).

  US 5,726,026 (Univ. Pennsylvania) and US 5,928,880 (Univ. Pennsylvania) describe a microfluidic device comprising a detection / reaction zone containing a solid phase in the form of particles. It is described in. Streptavidin is immobilized on the particles. The particles can be dried or lyophilized.

  US 6,479,299 (Caliper) discusses the pre-distribution of soluble and insoluble reagents (assay components) during the manufacture of microfluidic devices.

  Applicants have identified a microscale fluid containing a plurality of microchannel structures, each containing a column of reversed-phase solid phase material (hydrophobic beads) (WO 02057775 (Gyros AB) and WO 02075776 (Gyros AB)). A device (Gyrolab MALDI SP1) is commercially available. The solid phase material is in a dry state. The device packaging is specially designed to ensure that the beads are held in place during storage and transport.

  WO 00056808 (Gyros AB), WO 01047437 (Gyros AB), WO 01054810 (Gyros AB), WO 02057775 (Gyros AB) and WO 02075776 (Gyros AB) generally deliver microfluidic devices in dry form. Suggested in terms.

  US 5,354,654 (Ligler et al) suggests a kit comprising a solid support with an immobilized ligand-receptor complex lyophilized with a freeze stabilizer. Support packing in a macroscale column is suggested.

  US 5,998,155 (Squibb) and US 5,691,152 (Squibb) describe compositions with high biotin binding activity. The biotin binding moiety is immobilized on a polymer support. The support can be in the form of beads, (a) a filler that protects the beads from damage during freeze-drying and helps the beads re-swell, (b) chemistry during freeze-dry and storage. It can be lyophilized together with a protective agent that inhibits the reaction, (c) a buffer, and the like.

There are a number of technical problems associated with providing a type of microfluidic device discussed above in the background problem market. We have found that if a customer attempts to introduce a hydrophilic porous bed into the equipment, there is a high risk of getting a malfunctioning bed. Overall, this will lead to increased variability between and within devices in the performance of the floor / microchannel structure, reduced sensitivity and reproducibility for assays performed within the structure, and the like.

  In the macro world, a general trend has been to provide packed columns with solid phase based separation media in the form of wet beds. The loss of liquid during storage due to evaporation is typically low compared to the overall volume. The situation is quite different for microfluidic devices where the bed volume is typically in the nl-range and evaporation becomes readily noticeable due to wicking. The result is a high risk for rapid uncontrolled drying of the bed and an unacceptable risk for the creation of a mix of channels, cavities and air that will disturb the liquid flow characteristics of the bed. For solid phase materials containing biologically active reactants, the risks for non-renewable and irreversible changes in activity are also apparent. Fully or partially dried solid phase material in a microfluidic device can be combined with fluid flow characteristics and bonding, with essentially the same channel-to-device variations between the wet bed prior to drying. There are difficulties to reconstitute into a finely aligned and uniform porous bed / column with activity.

  These problems are typically more pronounced for solid phase materials that are hydrophilic and / or swellable in water than are hydrophobic that do not swell in water. See Figures 2a-b and 3.

Our experience with wet hydrophilic floors has instilled the idea that the floor should be dried under controlled conditions. However, it has further proved difficult to achieve a dry solid phase material that could be reconstituted into a fine porous bed / column in a desirable manner, eg
Solid phase materials typically carry reactants that are sensitive to drying, storage and transport.
• The binding of solutes to the porous bed in the microfluidic device can be monitored spectroscopically through a detection window associated with the porous bed. The creation of undesirable channel, cavity and air mixing will increase the noise level for detection and thus also reduce sensitivity and reproducibility.
There is a significant risk that during the transport of a microfluidic device with a porous bed, solid phase material can leak out of the microcavity. The danger to the loss of dispensed reagents and analytes by reaction with leaked solid phase material at undefined locations within the microchannel structure is obvious.
This type of problem is most serious if the floor is made of particles.

It is an object of the invention to provide an improved microfluidic device that solves the problems discussed above. Thus, the purpose of the drying can be reconstituted after storage and transport of the equipment into a wet bed with essentially the same performance as a wet bed of the same solid phase material that has not been converted to a dry state. Providing a microfluidic device comprising a solid phase material in a state. If the solid phase material contains an immobilized reactant, its activity, eg, binding activity, such as the ability to bind solutes, is essentially unchanged by conversion to dry state, storage, transport and reconstitution. There will be. This is especially true for activity under flow conditions.
The object includes providing a method for the manufacture of the device and, inter alia, the use of the device for separation and / or assay purposes.

FIG. 1 shows a subgroup (100) of microchannel structures (101a-h) of a microfluidic device utilized in the experimental part.

Figures 2a and b show a swellable solid phase material in particle form (Superdex® peptide, Amersham Biosciences, Uppsala, Sweden) placed in a microreaction space (104a-h). In FIG. 2a, the particles are lyophilized. The particles are grouped and randomly distributed in a micro reaction space. There is no packed bed. Figures 2a and b show a swellable solid phase material in particle form (Superdex® peptide, Amersham Biosciences, Uppsala, Sweden) placed in a microreaction space (104a-h). In FIG. 2b, the solid phase material is aligned and reconstructed into a wet porous bed.

FIG. 3 shows monodispersed essentially non-swellable and hydrophilic particles packed in a porous bed and lyophilized in a microreaction space (104a-h). The floor looked essentially the same after reconfiguration (not shown).

Figures 4a and b show the effect of drying (lyophilization) with potassium phosphate buffer on the performance of a packed bed of particles on which streptavidin is immobilized. The fluorescence intensity is typically shown radially through the floor (floor length) with a peak at the doorway. The direction of flow is from right to left. Store at + 4 ° C for one month. The effect was measured with a fluorescent myoglobin immunoassay (shown below) at four different concentrations of myoglobin and compared to the performance of a bed of identical material that was not dried (lyophilized) (slurry). The myoglobin concentrations were 4.56 nM (Graph 4), 22.8 nM (Graph 3), 91.2 nM (Graph 2) and 273.6 nM (Graph 1). FIG. 4a is after lyophilization and storage with potassium phosphate. Figures 4a and b show the effect of drying (lyophilization) with potassium phosphate buffer on the performance of a packed bed of particles on which streptavidin is immobilized. The fluorescence intensity is typically shown radially through the floor (floor length) with a peak at the doorway. The direction of flow is from right to left. Store at + 4 ° C for one month. The effect was measured with a fluorescent myoglobin immunoassay (shown below) at four different concentrations of myoglobin and compared to the performance of a bed of identical material that was not dried (lyophilized) (slurry). The myoglobin concentrations were 4.56 nM (Graph 4), 22.8 nM (Graph 3), 91.2 nM (Graph 2) and 273.6 nM (Graph 1). FIG. 4b shows no drying.

Figures 5a-d show the effect of three different drying procedures with a bed preservative (sugar variant, trehalose) on the performance of a packed bed of particles to which streptavidin is covalently bound. Storage and measurement are the same as for FIGS. FIG. 5a shows no drying. The myoglobin concentration for the various graphs is the same as in FIGS. Figures 5a-d show the effect of three different drying procedures with a bed preservative (sugar variant, trehalose) on the performance of a packed bed of particles to which streptavidin is covalently bound. Storage and measurement are the same as for FIGS. FIG. 5b is drying at atmospheric pressure (by wicking). The myoglobin concentration for the various graphs is the same as in FIGS. Figures 5a-d show the effect of three different drying procedures with a bed preservative (sugar variant, trehalose) on the performance of a packed bed of particles to which streptavidin is covalently bound. Storage and measurement are the same as for FIGS. FIG. 5c is vacuum drying. The myoglobin concentration for the various graphs is the same as in FIGS. Figures 5a-d show the effect of three different drying procedures with a bed preservative (sugar variant, trehalose) on the performance of a packed bed of particles to which streptavidin is covalently bound. Storage and measurement are the same as for FIGS. FIG. 5d is lyophilized. The myoglobin concentration for the various graphs is the same as in FIGS.

FIG. 6 shows the standard curve for the immunoassay shown in the experimental part with a sample of myoglobin (concentration of 0-274 nM myoglobin diluted in PBS with 1% BSA). Solid phase dried at atmospheric pressure (PS-PheDex-Streptavidin in 100 mM trehalose), stored at + 4 ° C. for 1 month. The y-axis indicates fluorescence and the x-axis indicates log concentration.

When intimately mixed with the solid phase material of the present invention , adverse effects such as pre-distribution, drying, storage, transport, reconstitution, etc. of the solid phase material intended to be used as a fine porous bed in a microfluidic device It has now been found that there are certain compounds and / or combinations of compounds that will reduce the. These adverse effects are for example:
a) unacceptable formation of channels, cavities, air, etc. and / or
b) leakage of solid phase material from a desired location within the microchannel structure, and / or c) reduced binding activity of an immobilized reactant, such as an affinity reactant.

  A compound or combination of compounds that reduces these adverse effects will subsequently help restore the dry solid phase material to an efficient wet porous bed, so it is a “bed preservative” or simply “preservative”. Will be called. In accordance with the principles of the invention, the bed preservative is simply contained in a liquid layer of wet solid phase material prior to drying / dehydration. Drying can occur inside the microfluidic device or outside. By using a suitable inlet device (102, 103a-h) and / or a single volumetric unit (108a-h), such as a distribution manifold (106a-h), as described herein, We have found that the accuracy for the formation of a predetermined volume of reconstituted wet bed can be further increased. Variations between channels due to drying, storage, transport and / or reconstitution of the filled solid phase material can be easily kept to a minimum.

  A common flow control as defined in WO 02075312 (Gyros AB) restores the volume of the porous bed wetted in parallel within the microreaction space of at least one subset of the microchannel structure of the microfluidic device. Sometimes it has also been found to be beneficial to increase accuracy. Centrifugal force is useful, for example, to improve the yield of an efficient porous bed if it is applied to settle and restore the bed.

First embodiment: microfluidic device This embodiment comprises one, two or more microreaction spaces (104a-h) each intended to hold a solid phase material in the form of a porous bed A microfluidic device comprising a microchannel structure (101). The device is a hydrophilic hydrophilic in the dry state, in which the microreaction spaces (104a-h) in one, two or more microchannel structures (101) contain compounds or combinations of compounds that act as bed preservatives. It includes a solid phase substance. These compounds thus ensure that an acceptable wet porous bed can be restored after the reconstituted liquid has passed through the dry solid phase material.
Floor preservative (s) include
a) a solid phase material, possibly containing an immobilized reactant (eg an affinity reactant)
(i) conversion of the solid phase material from wet to dry, and / or
(ii) Ability to stabilize during subsequent storage and / or transport, and / or b) to assist in reconstitution into a dry, wet porous bed.

  The term “acceptable wet porous bed” means that experimental results from the bed can be used, ie the bed is functional. The term “unacceptable” means that the experimental results are discarded. Thus, bed preservatives increase the probability of obtaining an acceptable bed. Thus, the use of the principles of the present invention allows the yield of a functional bed or microchannel structure on a microfluidic device to be ≧ 70% of the total number of microfluidic device floors or microchannel structures, such as ≧ 80% or ≧ 90%. Or it can help to increase to ≧ 95% or ≧ 98%.

  The term “dry” refers to the liquid present in the solid phase material when the amount of liquid remaining after drying is saturated with the liquid concerned (no free liquid layer appearing at the top of the bed). It means ≦ 50% of the quantity, for example ≦ 30% or ≦ 20% or ≦ 10%. In many cases, this means that the amount of liquid in the solid phase material after drying and / or storage is ≦ 20% (w / w), for example ≦ 10% or ≦ 5%. . Liquid typically refers to water.

Floor preservative (additive)
Porous bed damage during drying / dehydration and storage typically depends on stresses induced during the conversion from wet to dry in a manner similar to that for biologically active materials To do. The choice of bed preservative will depend on drying conditions, solid phase material, type of immobilization reactant, and the like. The same compound (s) can act as a bed preservative for one solid phase material and / or immobilization reactant, but can negatively affect other combinations. Thus, individual preservative candidates [either as a single compound or as a combination of compounds (s)] and conditions for conversion to a dry state and / or for storage and / or reconstitution It may be extremely important to test these conditions before using the candidate for a particular solid phase material. Testing is typically done by trial and error, and a) physical inspection of the bed to find unwanted channels, cavities and air contamination, and / or b) fluidity, activity of the immobilized reactants, Or the like.

The measurement of the activity of the immobilized reactant / ligand can be carried out using i) an activity profile in the flow direction and / or perpendicular to the flow direction (eg distribution of activity in the bed), ii) eg in a standard type assay or porous It may include measuring the total activity of the bed, etc., by testing the behavior of the bed with actual future use of the sex floor. If the immobilized reactant is an affinity reactant that can capture solutes, the distribution of solutes in the bed after adsorption (capture) can be used, for example, reactant channels, cavities, air inclusions, or localized Abnormal local behavior caused by inactivation can be found. The total amount of adsorbed solute can give an overall picture, eg, a measurement of the average state of the immobilized reactant after reconstitution. The adsorption for the test is preferably carried out under conditions where the flow, ie the liquid containing the solute, can flow through the porous bed. These types of tests are typically standard beds and / or a) the indicated values b) preset specifications c) the same type of freeze-dried lyophilized / dried solid phase material to be tested Includes comparison with standard behavior that can be given by the behavior of a bed prepared from solid / undried solid phase material, etc.

The sub-process with the greatest risk of damage is mainly a drying process (dehydration process) and storage in that state. The freeze process can also cause significant damage if lyophilization is part of the conversion. For biologically active substances, it is well known that specific stabilizers may be required for each substep. Therefore, stabilizers are named according to the type of sub-process in which they are active, for example, frozen stabilizer refers to freezing, dissolution stabilizer refers to dehydration / drying, and long-term stabilizers are stored. Point to. See, for example, Arakawa et al (Advanced Drug Delivery Reviews 46 (2001) 307-326). In the context of the present invention, a similar classification is used for floor preservatives.
Compounds that aid in the reconstitution of dry solid phase material into a wet porous bed are called bed reconstituting agents and are bed preservatives.

  The bed preservative may be active with respect to at least one to all steps: drying / dehydration, freezing, storage and reconstitution. The potency of a particular agent will depend on the conditions of the particular process, the solid phase material and / or the immobilization reactant to be stabilized.

  The floor preservative useful in the present invention is typically hydrophilic in the sense that it is water soluble. Thus, many bed preservatives typically have one or more heteroatoms selected from oxygen, nitrogen and sulfur, between the total number of carbon atoms and the total number of oxygen, nitrogen and sulfur atoms. The ratio is ≦ 6, for example ≦ 4 or ≦ 2.

  Typical bed preservatives include: a) a carbohydrate structure that also includes a sugar alcohol structure, b) a polyhydroxy structure (ie, an organic polyol that also includes a polyhydroxy polymer), c) an amino acid structure that includes a peptide structure and an imino acid structure. D) inorganic salts, e) organic salts, in particular carboxylates, f) amine structures including amino acid structures and ammonium structures, h) and the like.

  Suitable compounds with carbohydrate structures are substituted with sucrose, lactose, glucose, trehalose, maltose, isomaltose, cellobiose, inositol, ethylene glycol, glycerol, sorbitol, xylitol, mannitol, optionally at one or both of its ends. Polysaccharides including polyethylene glycol, dextran, maltodextrin, monosaccharides, disaccharides and oligosaccharides can be found. The compound having a carbohydrate structure is also typically a polyol.

Suitable polyols are polysaccharides such as polyvinyl alcohol, poly (lower hydroxyalkyl (C _2-4 ) acrylic acid, optionally partially substituted on the hydroxy group by acetate or lower hydroxyalkyl groups (C _2-4 ). Ester) polymers and the corresponding polymethacrylic acid ester polymers and the like, as well as monomeric compounds having two or more hydroxy groups. In a typical polyol, each hydroxy group is bonded directly to the sp ³ -hybridized carbon.

Suitable polymers are typically found among polymers having multiple functional groups containing heteroatoms selected from oxygen and nitrogen. Related functional groups are —O (CH ₂ CH ₂ O) _n — (where n is ≧ 2, eg ≧ 5), —CONH— or —CONH ₂ (wherein H is a suitable hydrophilic group) Amides, such as may be substituted with organic groups, hydroxy (OH), esters (-COOR where R is a suitable hydrophilic organic group), and the like. Specific examples are polyethylene glycol, dextran and other polysaccharides, polyvinyl pyrrolidone, polypeptides, the above-mentioned polyacrylate and methacrylate polymers, the above-mentioned polyvinyl alcohol, and the like.
The term “polymer” also includes copolymers that are part of the specific polymer referred to.

  Bed preservatives, which are dissolution stabilizers, are believed to act during the drying / dehydration process by replacing the water bound to the solid phase material to be stabilized. Thus, these bed preservatives are found primarily in compounds that can participate in hydrogen bonding / coordination with solid phase materials. With current knowledge, the most typical candidates for solution stabilization are, for example, polyols (including diols, triols, etc.) with polymer structures and / or carbohydrate structures (oligomers are included in the polymer) Found in. If the solid phase material comprises an immobilized reactant, for example with a peptide structure, the most effective candidates have a carbohydrate structure, preferably a disaccharide, and include sucrose, lactose, glucose, trehalose, maltose, It is believed to be found in isomaltose and cellobiose.

  Many times, suitable bed preservatives, such as dissolution stabilizers and stabilizers for long-term storage, are optionally mixed with one or more other components present in the microreaction space. It has the ability to exist in a glassy state in the reaction space.

  Bed preservatives present in the dry state of the solid phase material are typically non-volatile. This does not exclude that volatile freeze stabilizers are included during lyophilization.

Protective agent (additive)
The solid phase material in the dry state may also contain one or more so-called protective agents that inhibit undesired chemical reactions of the solid phase material and / or the immobilized reactant. Suitable protective agents are found among free radical scavengers, antioxidants, reducing agents and the like.

Other additive dry solid phase materials also have a non-volatile buffer component, such as at least one buffer component that is anionic, such as in phosphate buffer, citrate buffer, etc. A suitable buffer may be included, such as a buffer with two. Other buffering agents can also be used. The buffer component typically provides a high buffer capacity within a suitable pH range of pH 1-13, preferably in the range of 3-11. For the solid phase material to be lyophilized, a phosphate buffer having potassium as a counter ion is particularly preferred.
One or more antibacterial agents may also be included, for example other additives such as bacteriostatic agents, bactericides, antiviral agents and the like.

  Possible fillers can also be included as additives. The filler may have a bed preserving effect on the solid phase material as generally discussed above for the bed preservative.

  A microcavity adhesive (a kind of bed preservative) keeps the solid phase material in the microreaction space, thus helping to restore the dry solid phase material to the wet porous bed . Such drugs act by bringing the particles into close contact with each other and / or the inner walls of the microreaction space. Microcavity adhesives can be found among the bed preservative candidates discussed above, for example, those that exhibit carbohydrate and / or polymer structure.

  Various additives (bed preservatives, buffering agents, protective agents, fillers, etc.) typically range from 0.0001 to 25% of the solid phase material in the dry state, for example ≧ 0.00. It is present in an amount of 001% or ≧ 0.01% or ≧ 0.1% and / or ≦ 10% or ≦ 1%. These ranges apply to each individual additive as well as the total amount of additives, provided that the total amount should not exceed the upper limit of the range. Measuring the optimal range of effective amounts and the sufficient bed preservative effect of individual bed preservatives requires experimental testing as discussed above. The% value refers to the weight of the additive (s) relative to the total weight of the solid phase material in the dry state.

  Additives (stabilizers, buffer substances, protective agents, antibacterial agents and / or fillers) transport the liquid from the reconstituted porous bed, e.g., through the reconstituted wet bed ( It is typically soluble in aqueous media so that it can be easily removed by washing.

The microreaction space (104a-h) and the solid phase material microreaction space (104a-h) are defined as the part of the microchannel structure (101a-h) in which the solid phase exists. This means that for a solid phase in the form of a porous bed, the bed volume and the microreaction space (104a-h) will match and have the same volume. If the solid phase is the inner wall of the microconduit, the microreaction space (104a-h) is defined as the volume between the most upstream and the most downstream ends of the solid phase.

  The microreaction space (104a-h) is typically a straight or bent microconduit that may or may not continuously expand and / or narrow. In the same apparatus, all microreaction spaces typically have essentially the same shape and / or size. In a microfluidic device having a microreaction space according to the present invention of different shape and / or size, the microreaction space / microchannel structure (104a-h / 101a-h) is a Can be divided into groups containing minute reaction spaces that are not present in Each group may be located within a sub-area of the device that is separate from other groups of sub-areas.

  The microreaction space (104a-h) has at least one cross-sectional dimension that is ≦ 1,000 μm, for example ≦ 500 μm or ≦ 200 μm (depth and / or width). The minimum cross-sectional dimension is typically ≧ 5 μm, for example ≧ 25 μm or ≧ 50 μm. The total volume of the microreaction space is typically in the nl range, for example ≦ 5,000 nl, such as 1,000 nl or ≦ 500 nl or ≦ 100 nl or ≦ 50 nl or ≦ 25 nl.

A porous bed is a) a population of porous or non-porous particles, or b) a porous monolith.
The monolith bed may be in the form of a porous membrane or a porous plug.
The term “porous particles” has the same meaning as in WO 02075312 (Gyros AB).

  Suitable particles are spherical or spheroid (beaded) or non-spherical. Suitable average diameters for the particles used as the solid phase are typically found in the range of 1-100 μm, preferably ≧ 5 μm, for example ≧ 10 μm or ≧ 15 μm and / or ≦ 50 μm. Also smaller particles can be used, for example having an average diameter of up to 0.1 μm. The outlet ends (111a-h) of the microreaction space (104a-h) and the particle design should match each other so that the particles can be retained in the microreaction space (104a-h). Certain types of particles, particularly those of colloidal dimensions, can be agglomerated. In these cases, the size of the lumps should be within a given range, even if the lumped particles are even smaller by themselves. See, for example, WO 02075312 (Gyros AB). Diameter refers to the “hydrodynamic” diameter.

The particles used can be monodisperse (monosize) or polydisperse (polysize) in the same sense as in WO 02075312 (Gyros AB).
The solid phase material may or may not be transparent.

  The solid phase substrate can be made from inorganic and / or organic materials. Typical inorganic materials include glass, and typical organic materials include organic polymers. Polymeric materials include inorganic polymers, such as glass and silicone rubber, and organic polymers that can be synthetic or biological sources (biopolymers). The term biopolymer includes semi-synthetic polymers within which are polymer backbones derived from natural biopolymers. Typical synthetic organic polymers are cross-linked and are often obtained by polymerization of monomers containing polymerizable carbon-carbon double bonds. Examples of suitable monomers are hydroxyalkyl acrylates and the corresponding methacrylic esters, acrylamides and methacrylamides, vinyl and styryl ethers, alkene-substituted polyhydroxy polymers, styrene and the like. Typical biopolymers may or may not be cross-linked. In most cases they exhibit carbohydrate structures such as agarose, dextran, starch and the like.

The term “hydrophilic” with respect to a porous bed intends sufficient wettability of the surface of the pores to water that is spread by capillary action (adsorption) throughout the bed when in contact with excess water. . This expression also means that the inner surface of the bed that comes into contact with water during adsorption will each expose a plurality of polar functional groups having heteroatoms selected, for example, in oxygen and nitrogen. means. Suitable functional group, a hydroxyl group, ethylene oxide group (in _{-X- [CH 2 CH 2 O-]} n ( wherein, n> a first integer, X is nitrogen or oxygen)), amino group An amide group, an ester group, a carboxy group, a sulfone group, and the like, and preferably a group that is essentially uncharged regardless of pH, for example, in the range of 2-12. For a particulate solid phase material, this means that at least the outer surface of the particle should exhibit polar functional groups. The hydrophilic functional group may be present on or part of a so-called extender arm (tentacle).

  If the solid phase substrate is hydrophobic or not sufficiently hydrophilic, for example based on styrene (co) polymers, the surface to be contacted with the aqueous liquid can be rendered hydrophilic. Typical protocols include coating with a compound or mixture of compounds that exhibit the same type of polar functionality as discussed above, treatment with oxygen plasma, and the like.

The dry solid phase material may be swellable when in contact with the reconstituted liquid. Swellable materials are further susceptible to problems associated with (a) shrinkage / swelling after reconstitution and non-uniform filling and / or flow-through and / or (b) leakage of dry particles during storage and transport. looks like. In this regard, the term “swellable” refers to a substance (particles per se or particles) when a dry substance (as defined above) comes into contact with a reconstituted liquid (which can be aqueous such as water). It means that an increase in the volume of the monolith) can be detected. The increase in volume can be, for example, ≧ 10% or ≧ 75% of the volume of the dry substance. Solid materials that are not swellable according to this definition are considered non-swellable.
The solid phase material can be rigid or elastic.

  The solid phase material may or may not contain an immobilized reactant that has the ability to participate in organic, inorganic, biochemical reactions, etc. with the solute. Depending on the situation and the type of reactant and solute, the interaction between the immobilized reactant and solute can be part of a separation process, catalytic reaction, solid phase synthesis, solid phase derivatization, and the like.

Immobilized reactant will now illustrated by a solute (S) affinity for partner _{(affinity counterpart) (AC S)} , affinity reactants that are capable of forming a solute and an affinity complex (AC S _-S) Is done. Affinity binding is typically based on (a) electrostatic interactions, (b) hydrophobic interactions, (c) electron-donor acceptor interactions, and / or (d) bioaffinity binding.
Bioaffinity binding is typically complex and includes a combination of interactions, such as (a)-(c) above.

Thus, the immobilized affinity counterpart (AC _S) is:
(a) electrically charged or chargeable, ie positively charged nitrogen (eg primary, secondary, tertiary or quaternary ammonium groups and amidinium Groups) and / or negatively charged groups (eg, carboxylate groups, phosphate groups, phosphonate groups, sulfate groups and sulfonate groups); and / or
(b) contains one or more hydrocarbyl groups and other hydrophobic groups; and / or
(c) optionally hydrogen and / or sp-, sp ² - and / or sp ³ - bonded to hybridized carbon, including one or more heteroatoms (O, S, N); and / or
(d) including a combination of features (a) to (c),
It can happen.

  A bioaffinity reactant / ligand is a member of a bioaffinity pair. Exemplary bioaffinity pairs are: a) antigen / hapten and antibody, b) complementary nucleic acid, c) immunoglobulin binding protein and immunoglobulin (eg, IgG or its Fc-part and protein A or G), d) Lectins and corresponding carbohydrates, e) biotin and (strept) avidin, e) members of the enzyme system (enzyme substrates, enzyme cofactors, enzyme inhibitors, etc.), f) IMAC groups and histidyl and / or cysteinyl and / or Or an amino acid sequence of a phosphate esterified residue (ie, IMAC motif), etc. Antibodies include antigen-binding fragments and antibody mimetics. The term “bioaffinity pair” also includes affinity pairs in which one or both members are synthetic, eg, mimics one or both of the natural bioaffinity pairs. The term IMAC means immobilized metal chelate.

The term “affinity reactant” also includes reactants that are capable of reversible covalent binding, eg, by formation of disulfides. The reaction of this type is typically, HS- or -S-SO _n - represents a group (n = 0, 1 or 2, the free valence is attached to a carbon). See US 5,887,997 (Batista), US 4,175,073 (Axen et al), and 4,563,304 (Axen et al).

  The immobilization reactant / ligand (affinity reactant) can also be a catalyst system or a member of a catalyst system, such as a catalyst, cocatalyst, cofactor, substrate or cosubstrate, inhibitor, promoter, and the like. For enzyme systems, the corresponding members are enzymes, cocatalysts, cofactors, coenzymes, substrates, cosubstrates and the like. The term “catalytic system” also refers to a chain catalyst system, for example a series of systems in which the product of the first system is a substrate such as a second catalyst system and the entire biological cell or part of such a cell. including.

Immobilized Affinity reactant (AC _S) should be selected to have an appropriate selectivity and specificity to interact with solute of interest with respect to the solid phase material with respect to the intended application. General methods and criteria for the proper selection of affinity reactants and reaction conditions are well known in the art.

Immobilized Affinity reactant (AC _S) and solute affinity constant for the formation of a complex comprising _{(S) (K S - AC} = [S] [AC S] / [S - AC S]) is applied It is an important criterion for optimizing and varies depending on the application. For affinity assays, the affinity constant is typically ≦ 10 ⁻⁸ mole / l or ≦ 10 ⁻⁹ mole / l. This type of assay is typically a sample solutes in response to flow conditions and immobilized AC _S and animal or organism samples (animal or organisms, such as human patients and other animals, mammals Related to the amount of analyte in animals (including samples from animals as well as from laboratory animals). This does not exclude that affinity partners with even weaker affinity can be used for this type of sample, other samples and affinity assays, and other applications. Thus, depending on the application, the affinity constant is relatively large, such as up to 10 ⁻³ mole / l or up to 10 ⁻⁴ mole / l or up to 10 ⁻⁵ mole / l or up to 10 ⁻⁷ mole / l. Or less than 10 ⁻⁸ mole / l or less than 10 ⁻¹¹ mole / l.

  Reactant / ligand immobilization techniques may be selected among techniques commonly known in the art. Thus, binding to a solid phase material can be via covalent binding, affinity binding (eg, biospecific affinity binding), physical adsorption, and the like.

Immobilization via affinity binding may utilize an immobilized affinity pair in which one of the members (immobilized ligand or L) is tightly bound, eg, covalently, to a solid phase material. . Another member of the pair (immobilized binding agent, B) is used as a conjugate comprising an affinity counterpart AC _S to binder B and solute S (immobilized conjugate). Examples of immobilized affinity pairs are: a) streptavidin / avidin / neutravidin and biotinylated reactant (or vice versa), b) antibody and haptenated reactant (or vice versa), c) IMAC group As well as amino acid sequences containing histidyl and / or cysteinyl and / or phosphoesterified residues linked to or part of the reactant (ie, IMAC motif).

  The term “conjugate” refers primarily to covalent conjugates, where both moieties have a peptide structure, such as chemical conjugates and recombinantly produced conjugates. The term also refers to so-called natural conjugates, i.e. affinity reactants that are spaced apart from each other and show two binding sites that direct affinity towards two different molecular elements, e.g. on one side of the molecule. Include natural antibodies that contain species and class-specific determinants on (= part) and antigen / hapten binding sites on the other side (= part).

  The immobilized ligand L has two or more binding sites for the immobilized binder B and / or the immobilized binder B has one, two or more binding sites for the ligand L. It is believed to be advantageous to have (or vice versa).

Preferred immobilized affinity pairs (L and B) typically have an affinity that is at most equal to or greater than the corresponding affinity constant for streptavidin and biotin, ≦ 10 times or ≦ 10 ² times or ≦ 10 ³ times greater Constant (K _L−B = [L] [B] / [L−B]). This will typically mean affinity constants that are approximately ≦ 10 ⁻¹³ mole / l, ≦ 10 ⁻¹² mole / l, ≦ 10 ⁻¹¹ mole / l and ≦ 10 ⁻¹⁰ mole / l, respectively. . Preferably, L and B are selected among biotin binding compounds and streptavidin binding compounds, respectively (or vice versa).

The affinity constants discussed above, Biacore (Uppsala, Sweden) by the biosensor (surface plasmon resonance) from, i.e., affinity reactants to be immobilized on the gold surface was coated with dextran (AC _S and L ) Refers to the value obtained.

At least one of the members of the affinity pair to be used in the present invention, in particular the bioaffinity pair, comprises a) an amino acid structure comprising peptide structures such as poly and oligopeptide structures, b) a carbohydrate structure, c) a nucleic acid structure. It typically shows a structure selected among: a nucleotide structure comprising, d) a lipid structure such as a steroid structure, a triglyceride structure and the like. In this regard, the affinity pair of terms, immobilized affinity pair (L and B), refers to an immobilized affinity reactant and the solute (AC _S and S) as well as other affinity pairs can be used.

The solid phase material in a dry state can be in an activated form otherwise. In other words, it is ready for direct covalent immobilization by reaction with the functional group of the desired reactant. The functional groups that can be used on the desired reactant are typically selected among electrophilic and nucleophilic groups so that the activating group is nucleophilic or electrophilic, respectively. Depends on whether or not. Examples of functional groups that can be used are amino groups and other groups including substituted or unsubstituted —NH ₂ , carboxy groups (—COOH / —COO ⁻ ), hydroxy groups, thiol groups, keto groups, and the like.

Other features of the microfluidic device The microchannel structure (101a-h) of the microfluidic device comprises a functional part that allows the entire protocol of the experiment to be performed within the structure. Thus, the microchannel structure (101a-h) of the microfluidic device is a) for example with inlet / inlet holes (105a-b, 107a-h), possibly together with volumetric units (106a-h, 108a-h). Inlet device (102, 103a-h), b) microconduit for liquid transport; c) microreaction space (104ah); d) micromixing space / unit; e) separation of particulate matter from liquid A unit for separating the components dissolved or suspended in the sample from each other, eg by capillary electrophoresis, chromatography, etc .; g) micro detection space; h) waste conduit / microcavity (112, 115a-h); i) valves (109a-h, 110a-h); j) vents to ambient air (116a-i); etc: One, two, three or more functional parts selected from The functional portion can have more than one functionality, for example, the microreaction space (104a-h) and the microdetection space can be matched. The various types of functional units in the microfluidic device are Gyros AB / Amersham Pharmacia Biotech AB: WO 99055827, WO 99058245, WO 02074438, WO 02054312, WO 03018198 (US 20030044322), WO 03034598, SE 03026507 (SE 00004617). , US SN 60 / 508,508), SE 0315393 (US SN 60 / 472,924) and Tecan / Gamera Biosciences: described in WO 0107487, WO 0108486, WO 00007285, WO 00007455, WO 00006560, WO 98007019, WO 098053311. Has been.

  In an advantageous manner, the microreaction spaces (104a-h) intended for a hydrophilic porous bed have their respective inlets (105a-b, 107a-h) and at least one volumetric unit (106a-h, 108a-h) connected to one or more inlet devices (upstream) (102, 103a-h). In one advantageous variant, there is one separate inlet device (103a-h) per microreaction space (104a-h) intended to contain the microchannel structure (101a-h) and solid phase material. In another advantageous variant, the inlet device (102) comprises all or a subset (100) of the microreaction space (104a-h) intended to contain the microchannel structure (101a-h) and the solid phase material. A common inlet (105a-b) and one volumetric unit (106a-h) for each microchannel structure / microreaction space (101a-h / 104a-h) of the subset (100). It has a distribution manifold.

  In both variants, each of the volumetric units (106a-h, 108a-h) in turn communicates with its microchannel structure (101a-h), for example the downstream part of the microreaction space (104a-h). ) The microchannel structures connected together by a common inlet device (102) and / or a common distribution manifold define a group of microchannel structure subsets (100). Each volumetric unit (106a-h, 108a-h) typically has a valve (109a-h, 110a-h) at its outlet end. This valve is for example a chemical surface property at the outlet end (WO 99585245 (Amersham Pharmacia Biotech AB)) and / or geometry, such as a boundary between a hydrophilic and a hydrophobic surface (hydrophobic surface cut). It is typically passive, taking advantage of changes in physics / physical surface properties (WO 98007019 (Gamera)).

  Typical inlet devices with inlets, volumetric units, distribution manifolds, valves, etc. are presented in WO 02074438 (Gyros AB), WO 02075312 (Gyros AB), WO 02077775 (Gyros AB) and WO 02075776 (Gyros AB). ing.

The microfluidic device may also include other common microchannel / microconduit connecting different microchannel structures. The common channel, including their various parts such as inlets, outlets, vents, etc., is considered the respective part of the microchannel structure with which they are communicating.
A common microchannel makes it possible to interpret microfluidic devices in which the microchannel structure forms a network. See, for example, US 6,479,299 (Caliper).

Each microchannel structure has at least one inlet hole (105a-b, 107a-h) for liquid and excess air (vent) (116a-i) and possibly also for liquid (waste channel (112) At least one exit hole.
The microfluidic device may also comprise a microchannel structure that has no microreaction space for holding solid phase material in accordance with the present invention.

  The microfluidic device contains a plurality of microchannel structures / devices that are intended to contain a solid phase according to the present invention. In this context, plural means two, three or more microchannel structures, typically ≧ 10, such as ≧ 25 or ≧ 90 or ≧ 180 or ≧ 270 or ≧ 360. As discussed above, the microchannel structure of the device can be divided into groups or subsets (100), each of which can be a manifold, a common waste, for example, depending on the size and / or shape of the microreaction space. It can be defined by a common microchannel (102, 112), such as a common entrance device (102) with channels (112) and the like. The number of microchannel structures in a group or subset is typically in the range of 1-99% of the total number of microchannel structures in the device, for example 5-50% or 5-25% or 10-50%. Is in range. This typically means that each group typically comprises 3-15 or 3-25 or 3-50 microchannel structures. Each group may be located in a specific area of the device.

  Different principles may be utilized to transport liquids in the microfluidic device / microchannel structure between two or more of the functional parts described above. Inertial forces can be used, for example, by rotating the disk as discussed in the next paragraph. Other useful forces are capillary forces, dynamic forces, capillary forces, non-dynamic forces such as hydrostatic pressure, and the like.

The microfluidic device is typically in the form of a disc. A preferred form has an axis of symmetry (C _n ) perpendicular to or coincident with the disc plane, where n is an integer of ≧ 2, 3, 4 or 5, preferably ∞ (C _∞ ). . In other words, the disc may be square, such as a square, and other polygonal shapes, but is preferably circular. Once the appropriate disc format has been selected, centrifugal force can be used to drive the liquid flow. Rotating the device about an axis of rotation that is typically perpendicular to or parallel to the disk plane can create the necessary centrifugal force. In most obvious variants on the priority date, the axis of rotation coincides with the axis of symmetry described above.

  For the preferred centrifugal force-based variants, each microchannel structure includes one upstream section that is at a shorter radial distance than the downstream section (from the axis of rotation). The microreaction space intended for the porous bed is typically in an intermediate radial position between the two sections.

  If centrifugal force is used for particle bed formation and / or reconstitution and / or to drive liquid flow through the bed, the microreaction space is directed radially outward from the axis of rotation. They are typically arranged together.

  Preferred devices typically have a size and / or shape similar to a conventional CD-format, for example, a size ranging from 10% to 300% of a circular disc with a conventional CD-radius (12 cm). It is a disk type. The upper and / or lower side of the disc may or may not be flat.

The microchannel / microcavity of the microfluidic device is from an essentially planar substrate surface that shows a lidless channel / cavity covered by another essentially planar substrate (lid) in the next step. Can be manufactured. See WO 91016966 (Pharmacia Biotech AB) and WO 01054810 (Gyros AB). Both substrates are preferably made from a plastic material, for example a plastic polymer material.
The adhesion activity and hydrophilicity of the internal surface should be balanced for application. See, for example, WO 01047637 (Gyros AB).

  The terms “wettable (hydrophilic)” and “non-wettable (hydrophobic)” mean that the surface has a water contact angle of ≦ 90 ° or ≧ 90 °, respectively. In order to facilitate efficient transport of liquid between different functional parts, the internal surfaces of the individual parts should be inherently wettable, preferably ≦ 60 °, for example ≦ 50 ° or ≦ 40. It has a water contact angle of ° or ≤30 ° or ≤20 °. These wettability values apply to at least one, two, three or four inner walls of the microconduit. If one or more inner walls have a higher water contact angle, this can be compensated by a lower water contact angle for the inner wall (s). In particular, the wettability in the inlet device should be adapted so that once the liquid begins to enter the cavity, the aqueous liquid can fill the intended microcavity by capillary action (self-suction). It is. The hydrophilic internal surface in the microchannel structure is a vent that simply functions as a vent to, for example, a passive valve, an anti-wicking means, an ambient atmosphere (see FIG. In order to introduce one square), one or more local hydrophobic surface cuts may be included in the hydrophilic inner wall. See, for example, WO 99058245 (Gyros AB) and WO 02074438 (Gyros AB).

  Contact angle refers to the value at the working temperature, typically + 25 ° C., is static and is measured by the methods exemplified in WO 00056808 (Gyros AB) and WO 01047637 (Gyros AB) Can do.

Second embodiment: A method for the conversion of a plurality of wet porous beds into a dry / dehydrated state, optionally reconstituted into a plurality of wet porous beds. This embodiment is defined in the heading of this chapter. It is a method. This method
i) a microfluidic device comprising a plurality of microchannel structures (101) each comprising a microreaction space (104a-h) containing a hydrophilic porous bed saturated with a liquid containing a bed preservative. Providing,
ii) converting the bed in each microreaction space (104a-h) to a solid phase material in a dry and / or dehydrated state while being retained in the microreaction space;
iii) optionally reconstituting the solid phase material obtained in step ii) into a wet porous bed in each microreaction space (104a-h):
It consists of these processes.
This aspect also relates to a method for reducing channel-to-channel variations in a microfluidic device with respect to the performance of a reconstituted porous bed.

The solid phase material may or may not show reactants that can interact with the solute in the liquid aliquot that is subsequently introduced. Various properties are discussed below and elsewhere in this specification.
Step (iii) is carried out under flowing conditions with a residence time and flow rate through the bed, for example, as preferably discussed for the third aspect of the invention.

  A porous particle bed can be created by flowing a dispersion of particles through all or one or more subsets (100) of the microreaction space (104a-h) of the microfluidic device. The particles then settle to form a porous bed at the outlet end (111a-h) of each microcavity (104a-h). The formation of the bed can be facilitated by the use of gravity and / or the use of centrifugal force, the latter preferably acting along the flow direction of the respective microreaction space (104a-h). Desirable additives such as those discussed above are present in the liquid dispersion and / or are introduced by passing the additive-containing liquid through the bed after it has been formed. The microfluidic device together with the liquid-saturated bed containing the additive is stored until conversion to a dry state.

Porous monolithic floors are typically used during device manufacture, for example,
a) by polymerization, or b) by placing a ready-made porous monolith,
Introduced into each of the at least one subset (100) of the microreaction space (104a-h) of the microfluidic device.

  In option a), a preferred variant is to carry out the polymerization in a sealed manner with a microreaction space (104a-h) and a corresponding microchannel structure (101a-h). In option b), the preferred variant inserts a monolith while at least the microreaction space (104a-h) is not covered (and the rest of the microchannel structure (101a-h) is covered) It is to be. After introduction of the porous bed and, if necessary, sealing of the microcavity, the bed is saturated with a solution containing the preservatives discussed above and stored until conversion to a dry state.

Conversion of the bed to a dry state can be accomplished by removing the liquid under reduced pressure, for example, below and / or above the freezing point of the liquid in which the bed is saturated. Removal under reduced pressure and below the freezing point typically means lyophilization. Alternatively, the liquid is removed from the settled dispersion with or without warming to atmospheric pressure.
If the device is designed to drive liquid transport by centrifugal force, so-called spin-drying can be used. See the description of FIG. 1 in the experimental part.

Due to the small dimensions between the walls around the microreaction space and the internal edges, wicking will be an important factor in drying / dehydration / evaporation, especially at atmospheric pressure.
Reconstitution of a wet porous bed means that the reconstitution liquid can flow through each of the microreaction spaces containing the solid phase material in the dry state. See the experimental part.

  An important tool for treating solid phase material evenly and / or in parallel among several structures is the respective microchannel structure (101a-h) as discussed in the first aspect. In a preferred variant, it is to provide an inlet device (102 / 103a-h) that is common (102) to a group / subset (100) of microchannel structures / microreaction spaces (101a-h / 104a-h) . Thus, this type of design would facilitate parallel distribution of solid phase material and parallel reconfiguration and conditioning of the porous bed. Thereby, in order to achieve the best benefits of the present invention, at least the inlet device (102, 103a-h), the distribution manifold, and / or the individual volume metering units (106a-h, 108a-h) are described herein. Hydrophilic surface properties within the limits discussed elsewhere in the document, as well as at the exit of each volumetric unit (106a-h, 108a-h), preferably, for example, a local hydrophobic surface break It is important to provide a valve function (109a-h, 110a-h) that is passive (meaning no moving parts).

Third aspect of the invention: Use of the device The use of the innovative microfluidic device, broadly speaking,
(i) providing a microfluidic device according to the first aspect of the invention;
(ii) in a predetermined number of microchannel structures / reaction spaces (101a-h / 104a-h), preferably under dry conditions, to dry solid phase material into a wet porous bed Restructuring,
(iii) a liquid containing a solute (S ′) at a position upstream of the wet porous bed in one or more microchannel structures (101a-h) containing the wet porous bed. Providing,
(vi) transporting liquid through the wet bed in at least one of the one or more microchannel structures (101a-h):
It consists of the process.

Steps (i) and (ii)
These steps are in accordance with the first and second aspects of the present invention.

Steps (iii) and (iv)
The solute (S ′) is typically capable of interacting with a wet porous bed.
Step (iii) involves the solute (S ′) being formed or distributed in the device / microchannel structure. If applicable, formation is typically at or within a wet porous bed / microreaction space (104a-h). Distribution is typically to the inlets (105a-b, 107a-h) at a location upstream of the porous bed / microreaction space (104a-h).

  Steps (iii) and (iv) are performed to allow the interaction between the solute (S ′) and the porous bed to occur. As mentioned in the introduction, the process comprises (a) a separation process and / or (b) catalytic reaction, (c) solid phase synthesis, and / or (d) solid phase material / porous bed derivatization. Can be part of

Separation among others,
i) capturing, i.e., porous bed shows' affinity structure with ability to bind to) (affinity ligand, affinity reactant) (AC 'solute (S a _S'). As the liquid containing the solute (S ′) passes through the bed, the solute (S ′) will then be captured / bound to the porous bed via AC ′ _{S ′} . After passing through the porous bed, the liquid will lack or have a reduced amount of solute (S ′). AC ′ _{S ′} and S ′ would correspond to AC _S and S, respectively, discussed above.
ii) Size exclusion, ie the porous bed is more prone to retain smaller molecules compared to larger molecules. The solute (S ′) will be delayed relative to the movement of the liquid tip and therefore will initially be enriched in the wet porous bed.
iii) Electrophoresis, i.e. the porous bed, functions as a means of anti-convection and / or anti-diffusion. :
including.
For many separation protocols, a combination of two or more captures, size exclusions, electrophoresis, etc. is utilized, either in a continuous bed or in the same bed.

  Separation can be part of a purification or enrichment protocol for solutes present in the liquid. The solute separated from the liquid can be a contaminant or element to be purified, enriched, etc. Separation can be part of various types of affinity assays, including synthetic protocols, preparation protocols, cell-based assays, nucleic acid assays, immunoassays, enzyme assays, and the like.

  An affinity assay that utilizes a capture step to bind a solute to a solid phase material is typically intended to characterize the reaction variables involved in the affinity reaction of the assay. In this context, reaction variables have two main types: 1) variables related to affinity reactants, and 2) reaction conditions. Type 1 variables consist of two main subgroups: a) activities including presence and / or absence, concentrations, relative amounts, activities such as binding activity and enzyme activity, etc., and b) eg affinity constants , The nature of the affinity reactant, including the affinity itself, such as specificity. See WO 02075312 (Gyros AB). The molecular element for which a type 1 reaction variable is characterized is called an analyte.

  Catalytic reactions in the context of the present invention are those in which the solid phase material exhibits one or more immobilized members of the utilized catalytic system (e.g., affinity structure, affinity ligand, affinity reactant), while the same system. Other members include being solutes. Catalytic reactions involve the formation of an affinity complex between an immobilized member (affinity structure, affinity ligand, affinity reactant) and at least one solute member. At least one member corresponds to the substrate for the catalyst system. The reaction results in a product that typically has a different chemical composition and / or structure compared to the substrate. The product may or may not be immobilized on the bed during the reaction.

  The term “catalyst system” includes more complex variants including a single catalyst system and a series of linked single enzyme systems, whole cells, cell parts exhibiting enzymatic activity, and the like. The bed can function as a catalytic reactor, such as an enzyme reactor.

  The process during which interaction with the solute occurs is part of a catalytic assay, such as an enzymatic assay, to characterize one or more members of a catalyst system or other reaction variable (e.g., reaction conditions). It can be. The assay can be for measuring the activity of a particular catalyst, substrate, co-substrate, co-factor, co-catalyst, etc. in a liquid sample. The molecular element / elements corresponding to the activity to be measured are called the analyte / analytes. See, for example, WO 03093802 (Gyros AB).

  In the context of an assay, the term analyte is derived from the element to be featured in the original sample as well as the analyte that is formed during the assay and is quantitatively related to the analyte in the original sample. Contains the elements. The solute discussed above can be the original analyte or an analyte-derived element.

  Solid phase synthesis includes, for example, polymer synthesis, such as oligopeptide and oligonucleotide synthesis, and the synthesis of other small molecules on solid phase material. Immobilization reactants used in polymer synthesis may exhibit the structure of corresponding monomers, such as nucleotides, carbohydrates, amino acid structures, and mimetics of these structures. Also included is the synthesis of a library of immobilized members of a combinatorial library. Such members have a relatively low molecular weight (eg <10,000 Daltons including possible spacers to the polymer backbone).

In the context of the present invention, solid phase derivatization often has the goal of introducing an immobilized reactant or activated functional group onto a wet porous bed. Thus, solid phase derivatization involves the introduction of reactive structures or groups that allow immobilization of the desired reactants via covalent bonds or via affinity / adsorption bonds. Thus, starting from a wet porous bed that exposes the immobilized ligand L, and the immobilized conjugate (BR = S ′; B is the immobilized affinity binder B and R is immobilized. by passing the liquid containing should reactant R), the reaction product R is rigidly coupled vital on a porous bed and immobilized conjugate B-AC _S as discussed above for L Will be exposed. If R is affinity counterpart _{AC S (B-R = B} -AC S) for the solute S, on a porous bed caused to capture the solute S from liquid containing the solute S / to separate Can be used as discussed in

The transport during step (iv) includes the continuous flow of liquid through the porous bed or the liquid transport is stopped when the liquid is in the bed. Interactions between reactants and solutes immobilized on the bed can thus take place under flow conditions or under static conditions, respectively. We have previously found that if this type of reaction takes place under flow conditions, more information can be obtained regarding the reaction variables in the affinity reaction (WO 02075312 (Gyros AB)). Flow rate and / or residence time, for example, the amount of solute (S) adapted to be coupled to an affinity partner AC _S immobilized to the solid phase, with a perturbation of the minimum by diffusion (non-diffusion limiting conditions) Can be adjusted to reflect the actual reaction rate or affinity between the immobilized affinity reactant, typically AC _S , and the solute, typically solute S.

  This also applies to the present invention, but for applications where the main interest is the total amount of solutes to be bound / captured, capture under flow conditions utilizing either diffusion-limited or non-diffusion-limited conditions. Does not exclude that can be used. Thus, the appropriate flow rate through the porous bed depends on a number of factors, such as the immobilized reactants and solutes and their size, the volume of the microreaction space, the porous bed containing the solid phase material, and the like. Typically, the flow rate typically gives a residence time of ≧ 0.010 seconds, such as ≧ 0.050 seconds or ≧ 0.1 seconds, with an upper limit that is typically 2 hours or less, such as 1 hour or less. Should. Exemplary flow rates are within 0.01 to 1000 nl / sec, such as 0.01 to 100 nl / sec and more typically 0.1 to 10 nl / sec. These flow rate ranges can be useful for bed volumes in the range of 1-200 nl, such as 1-50 nl or 1-25 nl. Residence time refers to the time it takes for a liquid aliquot to contact the solid phase / porous bed in the microreaction space. These ranges are also applicable to other uses of innovative microfluidic devices including separations, catalytic assays, solid phase synthesis, solid phase derivatization and the like.

Best Mode The best mode of the present invention in the filing of this application is given in the experimental section, a solid phase shown with trehalose as a bed preservative and potassium phosphate as a further additive (buffer). A microfluidic device containing a substance and having a microchannel structure is shown in FIG.

Part of the experiment The microfluidic device used for the experiment was circular and had the same dimensions as a conventional CD (compact disc). This microfluidic device will continue to be called CD. The CD has 14 microchannel structures (101a-h) arranged in an annular zone around the center (rotation axis) of the disk with a common waste channel (112) for each group near the periphery. One group (100) was contained. A group (100) of eight microchannel structures (101a-h) is shown in FIG. 1, and FIGS. 1-2 of WO02075312 (Gyros AB) and WO03024548 (US 20030054563) (Gyros AB) and WO Similar to the group of microchannel structures illustrated in the corresponding figure of 030245598 (US 20030053934) (Gyros AB) and functions in the same manner. The dimensions have essentially the same size as in these earlier patent applications.

  Each subset (100) has one common inlet device (102), one separate inlet device (103a-h) per microchannel structure and one micro reaction space (104a-h) per microchannel structure. Eight microchannel structures (101a-h) are provided. A common inlet device for each microchannel structure (101a-h) a) two common inlets (105a-b) that will also serve as excess liquid outlets, and b) one volumetric unit (106a-h). The volumetric units (106a-h) will function as a distribution manifold for the downstream portion of the microchannel structure. Each of the separate inlet devices (103a-h) is part of only one microchannel structure and comprises an inlet (107a-h) and a volume metering unit (108a-h). Between the respective volumetric units (106a-h, 108a-h) and their downstream parts, respectively, there are preferably passive valve functions (109a-h, 110a-h). The microreaction space (104a-h) of the microchannel structure (101a-h) is downstream of both the common inlet device (102) and the separate inlet device (103a-h) of the microchannel structure (101a-h). To position.

  At the exit end (111a-h) of each microreaction space, the depth is lowered from 100 μm to 10 μm in two steps to prevent particles from leaking out of the microreaction space. Each microreaction space (104a-h) is in the downstream direction connected to the outlet microconduit (113a-h), illustrated as the outer bend in FIG. 1, and connected to the waste function (115a-h). Having outlet ends (114a-h). In the periphery there is a common waste channel (112). Vents (116a-i, hydrophobic cuts) along with valves (109a-h, hydrophobic cuts) define the volume of liquid aliquots to be distributed downstream from the respective volumetric units (106a-h). .

  By placing an appropriate amount of aqueous liquid at the inlet of the inlet device, capillary action will fill the volumetric unit (s) connected to the inlet with liquid. By rotating the disk about its center, liquid can be forced through the valves (109a-h, 110a-h) between the volumetric unit and the downstream part.

  If the microreaction space (104a-h) is located at a shorter radial distance from the axis of rotation than the outlet end (114) of the outlet microconduit (113), wetting-drying of a wet packed bed can be used. . This is independent of the shape of the outlet microconduit (113).

Experiment
Instrumented immunoassays are performed in an automated system. System (Gyrolab workstation type 2 prototype with laser-induced fluorescence (LIF) module, Gyros AB, Uppsala, Sweden), CD-spinner, holder for microtiter plate (MTP) and 5 syringe pumps, 2 And 2 with a robot arm with 10 capillary holders connected to it. Two of the capillaries transferred all reagents and buffers from the MTP to one of the two common inlets (105a-b) in the CD. The other eight capillaries transferred individual samples from the MTP to separate individual inlets (107a-h) in the CD.

  The Gyrolab workstation is a fully automated robotic system controlled by application specific software. Application specific methods within the software control the rotation of the CD at a precisely controlled rate, thereby controlling the movement of liquid through the microstructure as the application progresses. Special software was included to reduce background noise.

  See also WO 0205312 (Gyros AB), WO 030255548 and US 20030054563 (Gyros AB), WO 030255585 and US 20000003576 (Gyros AB), WO 03056517 and US 200301515663 (Gyros AB) and also www.gyros.com.

The solid phase bead material loaded into the microstructure of the solid phase, streptavidin immobilization, packing, drying / dehydration and reconstitution microfluidic device may be either porous or solid in nature. For example, polystyrene (PS) particles (15 μm, Dynal Biotech, Oslo, Norway) were selected for the solid phase. The beads were modified by passive adsorption of phenyl-dextran (PheDex) to create a hydrophilic surface and subsequently streptavidin (Immunopure Streptavidin, Pierce, Perbio Science UK Limited, Cheshire, United Kingdom) and CDAP chemistry ( They were covalently linked using Kohn & Wilchek, Biochem. Biophys. Res. Commun. 107 (1982), 878-884). Other particles such as Superdex peptide and Sepharose HP (Amersham Biosciences, Uppsala, Sweden) are also covalently linked using streptavidin and CDAP chemistry (without phenyl-dextran coating). Streptavidin-biotin is a well-known bioaffinity pair. Polystyrene particles are solid and are not swellable in the reconstitution liquid used. Superdex peptides and Sepharose HP are porous to many affinity reactants and can swell in the reconstitution liquid used.

Suspension of particles in potassium phosphate buffer (10 mM) after conjugation with streptavidin, with or without bed preservative (in this case sugar additive (10-100 mM)) or bed preservative Were distributed in the common distribution channel via the inlets (105a-b) and moved through the structure by centrifugal force. Centrifugal force combined with vents (109a-h, 113a-i) divides the suspension into common inlet devices (102) in equal quantities, each of which has its own micro reaction space ( 104a-h) forms a packed bed of particles (columns) packed in each microreaction space (104a-h) against a two-phase depth (111a-h) at the outlet end (111a-h) . The approximate volume of the column was 15 nl. The column / bed was dried / dehydrated by three different methods:
Drying at atmospheric pressure with the aid of siphoning: After spinning the microfluidic device containing the wet porous bed at 6000 rpm for 1 minute to remove as much liquid as possible, the device is placed in a jewelry box, It was enclosed in a polymer-coated aluminum bag.
Vacuum drying: A microfluidic device containing a wet porous bed was placed on a tray and placed in a vacuum drying oven (Heraeus vacutherm VT6060M). The temperature was set at 25 ° C. and the pressure was reduced to 0.1 mbar by vacuum. The apparatus was held at this pressure and temperature for half an hour until the product was dry. The pressure was then allowed to reach atmospheric pressure. The device was then placed in a jewelry box and enclosed in a polymer-coated aluminum bag.
Freeze drying (lyophilization): A microfluidic device containing a wet porous bed was placed on a tray and placed in a −80 ° C. freezer (the device was also placed in a normal −20 ° C. freezer). You can leave it for an hour). After a few minutes, the trays were transferred to a lyophilizer (Heto, LyoPro 3000) in which all columns in the apparatus were frozen and the condenser temperature was set at -57 ° C. The pressure was reduced (by vacuum) to 0.1-0.06 mbar. The apparatus was held at this pressure and temperature until all the ice had sublimed (approximately 12 hours or overnight). The pressure was then allowed to reach atmospheric pressure for 2 minutes before the chamber was opened and the lyophilized product was provided into the apparatus. The device was placed in a jewelry box and enclosed in a polymer-coated aluminum bag.

The apparatus is stored at + 4 ° C. for one month, after which the drying column is placed in 15 mM phosphate buffer (PBS) containing 0.15 M NaCl, 0.02% NaN ₃ and 0.01% Tween®20. Re-wet / reconstitute once at pH 7.4, rotating through a common distribution channel and at the appropriate speed. Each addition of solution delivers 200 nl of liquid to a separate column (104a-h). Finally, the function of the reconstituted bed was tested in the immunoassay shown below at four different analyte (myoglobin) concentrations and compared to the corresponding bed that had not been dried / dehydrated. The results are presented in FIGS. 4-5 and show that it is more or less essential to include a bed preservative to reconstitute the dried / dehydrated solid phase material into an effective wet porous bed. ing.

Immunoassay our myoglobin assay of capture antibody (= AC _S), monoclonal anti - myoglobin 8E11.1 (LabAS, Tartu, Estonia) the Sulfo-NHS-LC- biotin (Pierce, prod # 21335, Perbio Science UK Limited, Cheshire , United Kingdom). The protein concentration of monoclonal anti-myoglobin 8E11.1 was 1-10 mg / ml and after it was incubated for 1 hour at room temperature with a 3-fold molar excess of biotinylation reagent in 15 mM PBS supplemented with 0.15 M NaCl. Gel through either NAP-5 column (Amersham Biosciences, Uppsala, Sweden) or Protein Desalting Spin Column (Pierce, # 89849-P, Perbio Science UK Limited, Cheshire, United Kingdom) Filtered.

  To load streptavidin-immobilized particles with biotinylated antibody, at a concentration of 0.2-2 mg / ml of antibody (depending on how much streptavidin is packed in the column) The solution was distributed in the common distribution channel via the inlets (105a-b) and moved through the structure by centrifugal force. The flow rate through the column was controlled by the rotational speed (rotational flow 1). After the capture antibodies bind to the column, they are washed once by the addition of PBS (added with 0.01% Tween 20) to a common distribution channel (inlet 105a or b) followed by a rotation step. went.

  To demonstrate the myoglobin assay in the Gyrolab workstation, a six point standard curve was created (Figure 6). Samples of myoglobin (diluted in PBS supplemented with 1% BSA) with concentrations ranging from 0-274 nM were distributed by capillaries to individual inlets (107a-h). During the first two steps of the rotary flow method, a sample volume of 200 nl was defined in the volumetric units (108a-h). In order to reach suitable kinetic conditions under the capture step (binding myoglobin to 8E11.1), the sample flow rate should not exceed 1 nl / sec. The sample flow rate was controlled by rotational flow 2. After sample capture, the column was washed twice by adding PBS (added with 0.01% Tween 20) to a common distribution channel (inlet 105a or b) followed by a rotation step. Excess detection antibody (monoclonal anti-myoglobin 2F9.1 (LabAs, Tartu, Estonia)) was then added via a common distribution channel (inlet 105a or b), using a similar slow flow rate (rotating flow 3) . The detection antibody was labeled with the fluorophore Alexa 633 (Molecular Probes, Eugene, USA). Excess labeled antibody was washed away by four additions of PBS (added with 0.01% Tween 20) to a common distribution channel (inlet 105a or b) followed by a rotation step.

  The complete assay was analyzed in a laser induced fluorescence (LIF) detection module. See further WO 0205312 (Gyros AB), WO 030255548 and US 20030054563 (Gyros AB), and WO 03056517 and 10 / 331,399 (Gyros AB).

  An overview of the operating methods implemented in the system is presented in Table 1.

  Certain innovative aspects of the invention are defined in further detail in the appended claims. Although the invention and its advantages have been described in detail, various changes, substitutions and alterations can be made here without departing from the spirit and scope of the invention as defined in the appended claims. It should be understood that this can be done in Further, the scope of this application is not intended to be limited to the specific embodiments of the processing methods, machines, manufacture, material components, means, methods and steps described herein. Perform substantially the same function or achieve substantially the same results as the corresponding embodiments described herein, as would be readily recognized by the skilled person from the disclosure of the invention, Processing methods, machines, manufacturing, material compositions, means, methods or steps that may exist or will be developed later may be utilized in accordance with the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims (22)

A method of converting a plurality of wet porous beads to a dry / dehydrated state, wherein the dry / dehydrated state is optionally reconfigured into a plurality of wet porous beads, the method comprising:
i) a microfluidic device comprising a plurality of microchannel structures (101a-h), each comprising a bed preservative comprising one or more compounds having bed preservative activity Providing a microfluidic device comprising a microreaction space (104a-h) comprising a hydrophilic porous bed saturated with
ii) converting the bed in each microreaction space (104a-h) to a solid phase material that is dry and / or dehydrated while being retained in the microreaction space;
iii) optionally reconstituting the solid phase material obtained in step ii) into a wet porous bed in each microreaction space (104a-h);
A method comprising the steps of: The process according to claim 1, wherein step (iii) is carried out under flowing conditions. At least one of said one or more compounds a) represents a hydrophilic group which may or may not be nonionic, and b) is water-soluble. The described method. 4. A method according to any one of claims 1 to 3, characterized in that at least one of the one or more compounds is a polyol. The method according to any one of claims 1 to 4, characterized in that at least one of the one or more compounds exhibits a carbohydrate structure, for example a polysaccharide structure or an oligosaccharide structure. 6. A method according to any one of the preceding claims, characterized in that at least one of the one or more compounds is a disaccharide, preferably trehalose. The method according to claim 1, wherein at least one of the compounds is a microcavity adhesive. 8. A method according to any one of the preceding claims, characterized in that the liquid comprises a non-volatile buffer, for example a phosphate buffer which may contain potassium ions as counter ions. . The conversion to the dry state is effected under reduced pressure from a porous bed saturated with an aqueous liquid, e.g. above or below the freezing point of the liquid or with a porous bed saturated with water at ambient atmospheric pressure. 9. Process according to any one of claims 1 to 8, characterized in that it is achieved by drying with or without warming. 10. The method according to claim 1, wherein a) the solid phase material is in the form of porous or non-porous particles, and b) the porous bed is a packed bed of these particles. The method described in item 1. 11. A method according to any one of the preceding claims, characterized in that the solid phase material is swellable or non-swellable. 12. A microchannel structure (101) according to any one of claims 1 to 11, characterized in that each microchannel structure (101) is designed for driving a liquid flow by centrifugal force through at least part of the structure. Way. Solid phase material is immobilized reactant, typically comprising an affinity reactant AC _S for affinity capture solute S, according to any one of claims 1-12 method. Immobilized reactant is a member of the immobilized affinity pairs including an affinity partner B to L and L, and AC _S is affinity counterpart for solute S, the immobilization of the conjugate B-AC _S into the porous bed 14. The method according to claim 13, characterized in that it is the intended immobilized ligand L. Affinity constant (K _S -AC) for the formation of a complex (S--AC) between a solute (S) and an affinity partner (AC _S ) for the solute, ie (K _{S -AC} ) = [S] _{[AC S] / [S -} AC S] is characterized in that it is a maximum ¹⁰ -6 mole / l, the process described in claim 14. The affinity constant of the immobilized affinity pair, ie KL _{′ −− B ′} = [L ′] [B ′] / [L ′ −− B ′], is up to 10 ³ above the corresponding affinity constant for streptavidin and biotin. 16. The method of claim 15, characterized in that it is twice as large and preferably the affinity pair L 'and B' is selected (or vice versa) from a biotin-binding compound and a streptavidin-binding compound, respectively. 6. B has one or more binding sites for L and L has two or more binding sites for B, or vice versa. 16. The method described in 16. At least one of S and AC _S and / or at least one of L, B, AC _S and S, poly / oligo - peptide comprising the peptide structure and protein structure, carbohydrate structure, nucleotide structure comprising a nucleic acid structure, as well as lipid structures 18. A method according to any one of claims 13 to 17, characterized in that it comprises a structure selected from within. Step (iii)
(iv) providing a liquid containing a solute (S ′) upstream of the wetted porous bed in one or more microchannel structures (101a-h) comprising the wetted porous bed thing;
(v) transporting liquid through the wet bed in at least one of the one or more microchannel structures (101a-h):
The method according to any one of claims 1 to 18, wherein the method is performed by a method further comprising the steps of: 20. A method according to claim 19, wherein the solute (S ') can interact with the wet porous bed. The solute (S ′) is formed within the microfluidic device / microchannel structure, preferably upstream of or within the wet porous bed / microreaction space (104a-h); 21. Method according to claim 19 or 20, wherein the structure is distributed to the inlets (105a-b, 107a-h), preferably upstream of the porous bed / microreaction space (104a-h). Step (iv) or (v) is one of (a) separation method and / or (b) catalytic reaction, (c) solid phase synthesis, and / or (d) derivatization of solid phase material / porous bed. The method according to any one of claims 19 to 21, which is a part.

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