EP1671700A2 - Steuerung von Betriebsbedingungen in fluidischen Systemen - Google Patents
Steuerung von Betriebsbedingungen in fluidischen Systemen Download PDFInfo
- Publication number
- EP1671700A2 EP1671700A2 EP06002978A EP06002978A EP1671700A2 EP 1671700 A2 EP1671700 A2 EP 1671700A2 EP 06002978 A EP06002978 A EP 06002978A EP 06002978 A EP06002978 A EP 06002978A EP 1671700 A2 EP1671700 A2 EP 1671700A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- fluid
- channel
- temperature
- microchannel
- fluids
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
- B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
- B01L3/50—Containers for the purpose of retaining a material to be analysed, e.g. test tubes
- B01L3/502—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures
- B01L3/5027—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip
- B01L3/502723—Containers for the purpose of retaining a material to be analysed, e.g. test tubes with fluid transport, e.g. in multi-compartment structures by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip characterised by venting arrangements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
- B01L2200/00—Solutions for specific problems relating to chemical or physical laboratory apparatus
- B01L2200/06—Fluid handling related problems
- B01L2200/0684—Venting, avoiding backpressure, avoid gas bubbles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
- B01L2300/00—Additional constructional details
- B01L2300/08—Geometry, shape and general structure
- B01L2300/0809—Geometry, shape and general structure rectangular shaped
- B01L2300/0816—Cards, e.g. flat sample carriers usually with flow in two horizontal directions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
- B01L2300/00—Additional constructional details
- B01L2300/14—Means for pressure control
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
- B01L2400/00—Moving or stopping fluids
- B01L2400/04—Moving fluids with specific forces or mechanical means
- B01L2400/0475—Moving fluids with specific forces or mechanical means specific mechanical means and fluid pressure
- B01L2400/0487—Moving fluids with specific forces or mechanical means specific mechanical means and fluid pressure fluid pressure, pneumatics
Definitions
- Microfluidic systems have advanced to the point where they are beginning to supplant conventional technologies in biological, chemical and biochemical analyses.
- routine separation based analyses e.g., nucleic acid separations, protein sizing separations, and the like are now routinely performed in microfluidic systems, e.g., the Agilent 2100 Bioanalyzer and Caliper LabChip® systems.
- high throughput analytical operations e.g., pharmaceutical screening, high throughput genetic analysis, and the like, are also being transitioned from multi-well formats into microfluidic formats, such as the Caliper HTS sipper chip systems.
- These microfluidic systems have allowed for increases in throughput while requiring substantially smaller volumes of reagents, smaller equipment footprint, and having more reproducible, automatable, integratable operations.
- U.S. Patent No. 5,880,071 describes methods of reducing effects of electrokinetic biasing of reagents within electrically driven microfluidic channel systems.
- U.S. Patent No. 6,043,080 to Lipshutz et al. describes the use of gas venting membranes within a miniature chamber, to permit degassing of fluids within a miniature fluidic environment.
- the present invention is generally directed to methods of controlling environmental conditions within a fluidic system, where such environmental conditions can affect the operation of the system in its desired function, and fluidic channels, devices and systems that are used in practicing these methods.
- Such environmental conditions are generally directed to the fluids themselves, the movement of such fluids through these systems, and the interaction of these fluids with other components of the system, e.g., other fluids or solid components of the system.
- the present invention is directed to a method of moving a volume of a reaction mixture.
- the method comprises flowing a volume of a first fluid through a first channel segment, where the first fluid region comprises an environmental control reagent.
- a first volume of a second fluid is flowed into the first channel segment immediately before or after the step of flowing the volume of the first fluid through the first channel segment.
- the invention provides microscale channels that comprise a first fluid region disposed therein, the first fluid region comprising at least one environmental or operation control reagent.
- a second fluid region is also typically disposed therein, where the second fluid region comprises at least a first reactant.
- the present invention generally provides methods for optimizing the operation of microscale channel based systems through the use of environmental or operation control reagents within the fluids that are being transported through the capillary channels.
- the environmental or operation control reagents are transported in fluid regions that are different from fluid regions that contain the reagents of interest for a given analysis, although such reagents may optionally be disposed within the fluid regions that contain the reagents of interest.
- the phrase "environmental control reagent” or “operation control reagent” refers to a reagent that typically is not involved directly in the reaction of interest, but instead modifies, controls or provides an indication of the state of the environment within a microscale channel in which a reaction of interest is taking place, so as to control that environment or provide the user with information as to the state of that environment such that external controls may be applied.
- Some specific and preferred examples of environmental controls include modifying the surface characteristics of the microscale channel, adjusting the viscosity and/or the channel flow resistance, and reducing the potential for gas evolution within the channel.
- Operation control reagents that are used as indicators or diagnostic reagents typically include, e.g., pH indicators, redox indicators, conductivity indicators, and any of a variety of dyes or labels that indicate the presence or absence of particular species, e.g., proteins, nucleic acids, etc. Because the environmental control reagents are flowed through the microscale channels, either as a constant stream, or in periodic pulses, they continually modify and control the environment within those channels or provide constant indicators as to the state of that environment. This is a particularly useful function where one or more environmental conditions within a microscale channel can change over time or deteriorate with respect to the performance of the reaction of interest.
- serially oriented microfluidic analyses e.g., where analytes are separately and serially introduced into a microscale channel.
- the serial processing is also multiplexed using multiple separate channels, e.g., where a large number of different analytes are subjected to analysis by serially introducing each into a separate one of multiple parallel channels.
- spacer fluid regions are ideal vehicles for the environmental control reagents described herein.
- conditions for a given analytical reaction can be optimized without having to account for the presence of the environmental control reagent within the reaction fluid region.
- a wide variety of different analytes can be tested without having to mix them with these environmental control reagents.
- Figure 1 is a schematic illustration of a serial process analysis that includes multiple reaction fluid regions interspersed with spacer fluid regions that include environmental control reagents.
- reaction fluid regions 104, 108 and 112 are flowed through a microscale channel segment 102.
- Spacer fluid regions 106, 110 and 114 which include the environmental control reagents, are interspersed between the reaction fluid regions.
- the spacer fluid regions 106, 110 and 114 include the environmental control reagents as described herein.
- the reaction fluid regions optionally include the environmental control reagents, in preferred aspects the environmental control reagents are primarily contained within the spacer fluid regions.
- the environmental control reagent is flowed through the channel segment immediately following each region of reaction fluid, e.g., such that the fluid region containing the environmental control reagent(s) are interspersed among reaction regions.
- the environmental control reagent region is adjacent to and abutting the reaction fluid region, to optimize the environmental control function that those reagents perform.
- the period between environmental control reagent additions can be increased, e.g., after 2, 5, 10 or even 20 or more reaction fluid regions, and their optionally associated spacer fluid regions, have passed through the particular channel segment.
- an environmental control reagent may be transported through a channel only once or a few times for the lifetime use of a given channel structure, and may increase the useful lifetime of a channel network.
- one exemplary environmental control reagent type is a channel surface modifying reagent.
- surfaces can have properties, e.g., surface charges, hydrophobicity, etc., which promotes the sticking of proteins, cells or other reaction materials to those surfaces. This accumulation of material can subsequently interfere with material flowing or other aspects of a reaction of interest.
- electrically driven microscale channel systems the existence of charged functional groups on the channel surface can give rise to electrokinetic movement of fluids within channels, where such movement may be more or less desired.
- surface modifying reagents can be introduced into the channel in a separate fluid region that is flowed through the channel before and/or after the reaction fluid region. This can be repeated each time a new reaction fluid region is introduced into the microscale cannel segment or at pre-selected intervals, e.g., regularly spaced intervals. As these spacer fluid regions or plugs flow through the channel, they continually coat or re-coat the surface of the channels for a following reaction fluid region.
- surface modification reagents A wide variety of different materials are useful as surface modification reagents in accordance with the present invention.
- dynamic coatings that are typically comprised of surface adsorbing polymer solutions are used as the surface modifying reagent.
- polymer solutions include linear, e.g., non-crosslinked cellulose polymers, agarose polymers, acrylic polymers, e.g., polyacrylamides, and the like.
- Particularly preferred polymers include linear polyacrylamide polymers, and more particularly linear polydimethylacrylamide polymers (PDMA) and copolymers of these, e.g., PDMA co-acrylic acid polymers as described in U.S. Patent No.
- PDMA linear polydimethylacrylamide polymers
- the surface modifying reagent is provided in a first fluid region that is transported through a particular microscale channel, whereupon the reagent within the first fluid region modifies the surface of the channel.
- a second fluid region is preferably introduced into the channel following the first fluid region.
- the influence of those channel surfaces on the reaction is controlled as desired, e.g., minimized, reduced, increased, or otherwise altered for desired effect.
- an additional first fluid region e.g., containing the surface modifying reagent, is then transported through the channel after the reaction fluid region, to re-coat the channel surfaces. This ensures a consistent level of environmental control among different, serially introduced reaction fluid mixtures.
- the environmental control reagents of the invention can be used to counteract build-up of other reagents within a microscale channel by performing cleaning functions within the channel.
- microscale channels, and particularly uncoated microscale channels are very susceptible to deposition and accumulation of material within a flowing system, e.g., as a result of the surface charge or hydrophobicity of the channel surface. Such accumulation can affect the continued operation of a microfluidic system by affecting the concentration of reagents, interfering with detection techniques, etc.
- environmental control reagents that are flowed through the channels of the device include "cleaning" agents to remove any accumulated material from channel walls.
- such cleaning agents include acids (e.g., HCl), bases (e.g., NaOH), detergents, high salt solutions (NaCl, NH 4 SO 4 , and the like), zwitterionic solutions, e.g., amino acid solutions, nondetergent sulfobetaine (NDSB), and others.
- Acid or base solutions are typically used at concentrations of greater than 1 mM and preferably greater than about 10 mM, and in some cases greater than 50 mM.
- the environmental control reagents may be separated from sample material containing fluids by a strongly buffered spacer fluid region, e.g., to avoid damaging the sample material.
- Salt concentrations will generally vary depending upon the nature of the cleaning operation to be carried out and may be in excess of 10 mM and often in excess of 20 or even 50 mM. Similarly, in the case of detergents, a variety of detergents are commercially available and may be employed as desired as an environmental control reagent.
- Environmental control may also include control of the overall or average fluidic characteristics of a microscale channel or channel network.
- Flow resistance of a channel can be manipulated by adjusting the structural characteristics of the channel, e.g., its length, width and or depth. However, such manipulations are typically carried out at the time of manufacturing of the channel system and are not readily altered.
- Flow resistance can also be altered by altering the characteristics of the fluid flowing through the channels.
- by adjusting the viscosity of fluids flowing through channels one can alter the overall flow resistance of those fluids.
- certain fluid regions e.g., spacer fluid regions
- viscosity adjusting reagents may be used in accordance with the present invention, including polymeric reagents, e.g., cellulose, agarose, gelatin, polyacrylamides, i.e., PDMA and co-polymers thereof, PEGs and other polyalcohols, Ficoll, hydrogels, and the like.
- polymeric reagents e.g., cellulose, agarose, gelatin, polyacrylamides, i.e., PDMA and co-polymers thereof, PEGs and other polyalcohols, Ficoll, hydrogels, and the like.
- Another environmental characteristic that can pose potential problems in microfluidic channel systems, and for which the present invention is particularly suited is the variation in dissolved gases within fluids flowing through the channels of the system.
- fluids in microfluidic systems have the potential to evolve dissolved gases
- such gases can create substantial problems in microscale channels, including blocking or otherwise restricting flows in channel networks, which can substantially disrupt the efficient operation of those systems.
- the potential for gas evolution is increased where, as in many bioanalytical operations, temperatures are maintained at elevated levels to optimize assay conditions.
- many microfluidic operations involve the use of pressure gradients to manipulate fluids within microscale channel networks. Substantial changes in pressures can lead to outgassing within the channel system. For example, often fluid flow is driven by an applied vacuum, where the pressure drop across the channel network can result in substantial degassing of fluids within the channel networks, where those fluids are sufficiently saturated.
- an environmental control reagent comprises a fluid reagent that is capable of controlling dissolved gas levels within the channel system at levels that do not result in gas evolution within the channels under the conditions of operation.
- the environmental control reagent in this context is a fluid reagent, e.g., buffer, water, etc., that has a dissolved gas level that is far below the level where gas evolution would be expected in the operation that is being carried out, e.g., at the temperatures and pressures or vacuums involved within the microscale channel systems.
- this gas control fluid also has a dissolved gas level that is sufficiently below that of most, if not all of the other fluids that are used in the particular analytical operation, e.g., the reaction fluids, spacer fluids, etc. such that when all of the fluids are mixed, the resulting solution will not evolve gas under the operating conditions of the particular operation.
- the gas control fluid has such a low level of dissolved gas, it can serve to scavenge excess dissolved gases from the other fluid regions within the channel networks, e.g., the reaction fluid regions, where a degassing operation may not have been reasonably practicable and as a result may have dissolved gas levels that could result in gas evolution within the microscale channel system.
- a degassing operation may not have been reasonably practicable and as a result may have dissolved gas levels that could result in gas evolution within the microscale channel system.
- sample materials are subjected to numerous in-process, but out-of-channel manipulations, e.g., dilutions, mixing, etc. which would effectively negate any attempts at degassing.
- saturation refers to the gas saturation point of a given fluid under the then current conditions within a microscale channel. As a result, the saturation point, or gas solubility, of a particular fluid at one temperature and pressure will be different from the saturation point of the fluid at another temperature and/or pressure.
- the reduced level of dissolved gas within the gas control reagents is generally dependent upon the particular operation that is to be carried out, rather than being an absolute characteristic.
- desired operation is to be carried out within a microchannel structure at lower temperatures, higher absolute concentrations or levels of dissolved gas can be tolerated without evolution.
- lower dissolved gas concentrations are tolerated.
- negative pressures are applied to fluids within a channel, e.g., as compared to ambient pressure of the fluids prior to their introduction into the channel system, it is generally required that such fluids have lower dissolved gas concentrations in order to avoid outgassing within the channels.
- positively pressurized channels are generally capable of supporting fluids with higher dissolved gas concentrations.
- the level of acceptable dissolved gas in order to avoid any problems associated with gas evolution within the channels, e.g., bubble formation. For example, where one knows the temperature at which the fluid is maintained within the channel system, the amount of dissolved gas in some of the fluid reagents, and the amount of applied vacuum in a given channel, one can determine the acceptable level of dissolved gas within a spacer fluid, as well as the relative amount of that spacer fluid needed, to counter any potential of outgassing within the channel.
- the environmental control reagent must be at or below 75% saturation with air at room temperature and 1 atmosphere pressure.
- the gas control reagents are only required to be at a saturation level that is at or below that necessary to prevent outgassing of a given system under that system's operating conditions.
- the degassing fluid need only have somewhat less.
- the gas control reagent has a dissolved gas concentration that is less than 80%, more preferably, less than 60%, more preferably, less than 50%, and often less than 40%, 30% or even 20% of the saturation level of dissolved gas in any portion of the operation being carried out.
- the conditions which prevent outgassing will generally depend upon other conditions of the system, e.g., the applied pressure, the gas saturation level of the fluids within the channels and the gas saturation level of the fluids prior to entering the channel. Gas saturation is highly temperature dependent, e.g., colder fluids can dissolve larger amounts of oxygen than warmer fluids. Similarly, fluids maintained at a lower pressure will evolve more gas than fluids kept at higher pressure. Accordingly, by adjusting one or more of the temperatures of the fluids before and after entering a microfluidic channel network, and/or the pressure or vacuum applied to a system, one can ensure that the system operates under non-out-gassing conditions.
- the applied pressure is determined by the desired flow rate through the system, e.g., resulting from desired throughput or reaction times. Accordingly, prevention of outgassing is typically a matter of adjusting one or more of the temperatures of the fluids prior to entering the channels and after entering the device.
- a fluid that is maintained at a first temperature, but which is heated upon entering the channel network poses a substantial risk of bubble generation within the channels. This is particularly true where the flow of fluids in the channels is driven by vacuum.
- higher temperature differentials are desirable and may be 10, 20, 30 ° C or more, e.g., the temperature of the fluids prior to entering the channel network is 10, 20 or 30°C higher than the chip temperature.
- microchannels because fluids are often flowed through microchannels under an applied vacuum, the latter alternative is not optimally applicable in all situations.
- pressure adjustments are used to prevent degassing within the microchannel, it is typically applied as a preloading step, e.g., fluids are subjected to vacuum prior to loading into a channel.
- the fluids to be introduced are subjected to either one or both of an elevated temperature or reduced pressure environment immediately prior to introducing those fluids into the channels, to prevent re-equilibration of the fluids at atmospheric temperatures, and so as not to necessitate complex sealed bottle systems.
- "immediately prior to introduction” means 5 minutes or less before fluid introduction, preferably 1 minute or less, and often 30 seconds or less.
- a trough of fluids is continuously recirculated and subjected to elevated temperatures.
- gas control reagents comprise fluids having sufficiently low dissolved gas concentrations, e.g., buffers, water etc.
- gas absorbing additives may also be used in conjunction with this aspect of the present invention, in order to reduce the potential for outgassing during a given operation.
- intermediate fluid slugs in microfluidic channels can be put to a variety of other useful functions in microfluidics based analyses.
- spacer fluid slugs optionally incorporate signaling components, e.g., dyes, labels, etc., so as to provide an indicator component of the spacer slugs versus the sample slugs.
- signaling components e.g., dyes, labels, etc.
- Such indicators may be varied in terms of the nature of the label, e.g., in the case of fluorescent labels, via it's wavelength of excitation, emission, intensity or the like, to provide the ability to distinguish between spacer slugs at different points in an operation.
- a spacer slug early in an assay run may have a first signaling component, e.g., fluorescing at a first wavelength or combination of wavelengths, whereas later spacer slugs fluoresce at a different wavelength or combination of wavelengths.
- a first signaling component e.g., fluorescing at a first wavelength or combination of wavelengths
- later spacer slugs fluoresce at a different wavelength or combination of wavelengths.
- a first signaling component e.g., fluorescing at a first wavelength or combination of wavelengths
- later spacer slugs fluoresce at a different wavelength or combination of wavelengths.
- Spacer slugs containing signaling components may also be used as calibrators for detection systems used in conjunction with the devices and methods described herein.
- a known concentration of signaling component can be used to set detection system so as to optimally detect assay results.
- signaling components of spacer slugs can be used as indicators or diagnostics of other environmental conditions within a microscale channel system.
- temperature sensitive signaling components may be used to monitor temperature within such systems over the course of an assay run
- pH sensitive signaling components may be used to indicate intrachannel pH or changes therein.
- ion specific indicators, or generic conductivity indicators may be used.
- a variety of temperature sensitive signaling components may be used in conjunction with this aspect of the invention, including molecular beacons, self hybridizing nucleic acid sequences that become fluorescent when heated above their melting temperatures.
- pH indicating labels or dyes are widely available from commercial sources, including, e.g., Molecular Probes, Inc. (Eugene, OR). Dyes or labels can also be provided to indicate the level of macromolecular buildup within channels, which buildup might affect the functions of the channels, or their usefulness in a given analysis.
- Such dyes include protein indicators, nucleic acid indicators, and the like.
- the present invention is most useful in the context of analytical operations that are carried out within a sealed microscale channel environment.
- a sealed microscale channel environment includes a simple channel, e.g., a capillary, tube or other enclosed conduit through which fluid materials are flowed.
- the operations in question are carried out within more complex networks of microscale fluid channels, e.g., in microfluidic devices.
- microscale fluid channels e.g., in microfluidic devices.
- such devices include at least two different microscale channels disposed within the same single body structure.
- the at least two microchannels will be in fluid communication with each other, e.g., at a channel junction, to form an integrated channel network.
- microfluidic devices incorporating complex channel geometries have been previously described in, e.g., U.S. Patent Nos. 5,869,004, 5,942,443, 5,976,336, 6,042,709 and 6,068,752, each of which is incorporated herein by reference in its entirety for all purposes.
- the term microchannel typically refers to a channel conduit that has at least one cross-sectional dimension between 0.1 and 500 ⁇ m.
- at least one cross-sectional dimension of a microchannel is between about 1 and about 100 ⁇ m.
- microfluidic devices may be fabricated as an aggregate of different parts, e.g., capillaries and chambers, pieced together in a desired orientation
- such devices are fabricated in a monolithic format, integrated in solid substrates.
- microscale channels and channel networks are typically fabricated as grooves into a surface of at least one planar substrate layer.
- the first substrate layer is then overlaid with a second substrate layer, which is bonded to the first, to seal and enclose the grooves as microscale channels.
- Reservoirs or access ports are optionally provided in one or both of the substrate layers to provide access to the channels from the outside world. Additional substrate layers are optionally added to increase to the complexity of channel networks that may be produced.
- FIG. 2 provides a schematic illustration of the assembly of a layered microfluidic device.
- the device 10 includes a lower planar substrate 12 having a plurality of grooves fabricated into its surface.
- An upper substrate layer 18 is also provided that includes a plurality of apertures disposed through it.
- the apertures are positioned so as to be in communication with the grooves when the upper layer is placed upon and bonded to the lower substrate. This bonding also seals the grooves as enclosed channels or conduits.
- grooves and apertures may be disposed in either and/or both substrates depending upon the desired nature of the finished microfluidic device.
- microfluidic devices have been previously described, and include techniques commonly employed in the integrated circuit industries, e.g., photolithography and wet chemical etching, for silica based solid substrates, as well as other well known microfabrication techniques for other materials, e.g., injection molding and embossing techniques for polymer-based materials (see, e.g., U.S. Patent No. 5,885,470).
- Such devices are mounted on an instrument that includes fluid transport systems, as well as detection systems, whereby the instrument interfaces with the microfluidic device to control fluid movement and detect assay results within the channels of the microfluidic device.
- Such instruments are exemplified by, e.g., the Agilent Technologies 2100 Bioanalyzer and the Caliper Technologies HTS "Sipper" platform, as described at www.calipertech.com and www. Agilent.com, the contents of which are hereby incorporated herein by reference in their entirety for all purposes.
- Microfluidic devices, methods and systems that include serially introduced fluidic regions, e.g., as described in the preferred embodiments of the invention, are described in substantial detail in U.S. Patent Nos. 5,942,443, and 6,042,709, each of which is incorporated herein by reference in its entirety for all purposes.
- microfluidic devices are readily configured for operation on commercially available controller/detector instrument, e.g., an Agilent 2100 Bioanalyzer that is equipped with at least one pressure/vacuum source.
- controller/detector instrument e.g., an Agilent 2100 Bioanalyzer that is equipped with at least one pressure/vacuum source.
- higher throughput operations are readily configured to operate on sipper systems that are available from Caliper Technologies Corp.
- Such systems are described in detail at www.agilent.com and www.calipertech.com and in U.S. Patent Nos. 5,955,028, 6,042,709 and 6,071,478, each of which is incorporated herein by reference in its entirety for all purposes, as well as the patents described elsewhere herein, and incorporated herein by reference.
- the microfluidic device 300 includes a planar body structure 302 that includes a channel network disposed within its interior.
- the channel network includes a main analysis channel 304 that is coupled at one end to an external capillary element 306, via inlet 308.
- the main channel 304 is fluidly connected to reservoir/port 310.
- Two side channels 312 and 314 intersect and are in fluid communication with the main channel 304. These channels provide a connection between the main channel 304 and reagent reservoirs 316 and 318, respectively.
- sample material is sampled into the main analysis channel through the external capillary 306 by dipping the open end of the capillary into a source of sample material 320 and applying a vacuum at reservoir/port 310.
- the applied vacuum draws a slug of sample material into the capillary element 306 and moves it into the analysis channel 304.
- a spacer fluid is introduced after the sample material slug, in order to space the sample material from subsequent sample materials.
- the spacer buffer is sampled into the system the same way that the sample is drawn in. Specifically, the capillary element is placed into contact with the trough 322 of spacer buffer and a slug of spacer fluid is drawn into the system.
- main channel 304 additional reagents needed for a given analysis are brought into the main channel 304 from the side channels 312 and 314. Movement of reagents into channel 304 from these side channels is driven by the same vacuum used to draw materials in through the capillary element.
- the spacer fluid constituted the degassing fluid.
- Degassing parameters were calculated for a system having the attributes described with reference to Figure 3.
- a number of physical and temporal parameters of the operation of a microfluidic device are dictated by the particular analysis to be carried out therein.
- Those parameters were then used to calculate the maximal allowable level of oxygen within the spacer fluid in order for that fluid to function as a degassing reagent.
- a minimum spacer fluid trough temperature was calculated, e.g., to provide spacer fluid at an acceptable oxygen level.
- sample compounds are sipped for 2 seconds, while spacer fluids are sipped for 1 second.
- Transit time between the sample well 320 and the spacer fluid trough 322 is 1.5 seconds.
- flow into main channel 304 from the side channels is 50% of the total flow, e.g., 25% from each side channel.
- the temperature of the sample material is assumed to be room temperature or 22°C, while the device temperature is elevated to 28°C. This elevated temperature is generally desirable to accelerate analysis chemistries within the device.
- a vacuum of -0.3 psi is applied to reservoir/port 310 to drive fluid flow through the channels of the device.
- the first case is where a hanging droplet of fluid at the end of the capillary element does not equilibrate with air during the transit time from the sample to the trough.
- the second case assumes that the droplet becomes fully equilibrated with air during transit.
- the droplet should not equilibrate during a typical transit time, e.g., 1.5 seconds.
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Dispersion Chemistry (AREA)
- Analytical Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- Hematology (AREA)
- Clinical Laboratory Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Control Of Non-Electrical Variables (AREA)
- Automatic Analysis And Handling Materials Therefor (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US22307200P | 2000-08-04 | 2000-08-04 | |
EP01961834A EP1314016B1 (de) | 2000-08-04 | 2001-07-31 | Steuerung von betriebsbedingungen in fluidischen systemen |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP01961834A Division EP1314016B1 (de) | 2000-08-04 | 2001-07-31 | Steuerung von betriebsbedingungen in fluidischen systemen |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1671700A2 true EP1671700A2 (de) | 2006-06-21 |
EP1671700A3 EP1671700A3 (de) | 2007-02-14 |
Family
ID=36353942
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP06002978A Withdrawn EP1671700A3 (de) | 2000-08-04 | 2001-07-31 | Steuerung von Betriebsbedingungen in fluidischen Systemen |
Country Status (1)
Country | Link |
---|---|
EP (1) | EP1671700A3 (de) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102008031798A1 (de) * | 2008-07-04 | 2010-01-07 | Bürkert Werke GmbH & Co. KG | Verfahren zur Übermittlung von Informationen |
WO2012054794A1 (en) | 2010-10-22 | 2012-04-26 | Abbott Laboratories | Microfluidic device having a flow channel |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5922604A (en) * | 1997-06-05 | 1999-07-13 | Gene Tec Corporation | Thin reaction chambers for containing and handling liquid microvolumes |
DE10126056A1 (de) * | 2000-05-31 | 2002-01-10 | Abb Automation Ltd | Microanalyse |
-
2001
- 2001-07-31 EP EP06002978A patent/EP1671700A3/de not_active Withdrawn
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5922604A (en) * | 1997-06-05 | 1999-07-13 | Gene Tec Corporation | Thin reaction chambers for containing and handling liquid microvolumes |
DE10126056A1 (de) * | 2000-05-31 | 2002-01-10 | Abb Automation Ltd | Microanalyse |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102008031798A1 (de) * | 2008-07-04 | 2010-01-07 | Bürkert Werke GmbH & Co. KG | Verfahren zur Übermittlung von Informationen |
WO2012054794A1 (en) | 2010-10-22 | 2012-04-26 | Abbott Laboratories | Microfluidic device having a flow channel |
US8460607B2 (en) | 2010-10-22 | 2013-06-11 | Abbott Laboratories | Microfluidic device having a flow channel |
Also Published As
Publication number | Publication date |
---|---|
EP1671700A3 (de) | 2007-02-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9278354B2 (en) | Control of operation conditions within fluidic systems | |
WO2002012056A1 (en) | Saddle made of composite material, in particular for a bicycle, and method for the manufacture thereof | |
EP1314016B1 (de) | Steuerung von betriebsbedingungen in fluidischen systemen | |
EP1060023B1 (de) | Mikrofluidische geräte und systeme mit deckschichten | |
AU747464B2 (en) | Microfluidic devices, systems and methods for performing integrated reactions and separations | |
US6756019B1 (en) | Microfluidic devices and systems incorporating cover layers | |
JP4171075B2 (ja) | 改良されたチャネル幾何学的形状を組み込む微小流体装置 | |
US6669831B2 (en) | Microfluidic devices and methods to regulate hydrodynamic and electrical resistance utilizing bulk viscosity enhancers | |
EP1185850B1 (de) | Vorrichtung und verfahren zur probenabgabe | |
US7208320B2 (en) | Open-field serial to parallel converter | |
AU732462B2 (en) | Methods and apparatus for in situ concentration and/or dilution of materials in microfluidic systems | |
AU2001283069A1 (en) | Control of operation conditions within fluidic systems | |
US20040228770A1 (en) | Microfluidic devices and systems incorporating cover layers | |
US20100252128A1 (en) | Microfluidic device | |
US20020009392A1 (en) | Methods of reducing fluid carryover in microfluidic devices | |
US7033474B1 (en) | Microfluidic devices incorporating improved channel geometries | |
AU2006225228A1 (en) | Microfluidic devices and methods for chemical assays | |
AU2001261541A1 (en) | Microfluidic devices and methods to regulate hydrodynamic and electrical resistance utilizing bulk viscosity enhancers | |
US20090060786A1 (en) | Microfluidic apparatus for wide area microarrays | |
WO2001077641A1 (en) | Microfluidic devices and systems incorporating cover layers | |
EP1671700A2 (de) | Steuerung von Betriebsbedingungen in fluidischen Systemen | |
KR102458206B1 (ko) | 농도 구배 소자 | |
AU2477001A (en) | Microfluidic devices incorporating improved channel geometries |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20060302 |
|
AC | Divisional application: reference to earlier application |
Ref document number: 1314016 Country of ref document: EP Kind code of ref document: P |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
17Q | First examination report despatched |
Effective date: 20070810 |
|
AKX | Designation fees paid |
Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20090203 |