EP1397672A1 - Oxygen sensors disposed on a microtiter plate - Google Patents
Oxygen sensors disposed on a microtiter plateInfo
- Publication number
- EP1397672A1 EP1397672A1 EP02748791A EP02748791A EP1397672A1 EP 1397672 A1 EP1397672 A1 EP 1397672A1 EP 02748791 A EP02748791 A EP 02748791A EP 02748791 A EP02748791 A EP 02748791A EP 1397672 A1 EP1397672 A1 EP 1397672A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- oxygen
- matrix
- water
- dye
- permeable
- 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.)
- Ceased
Links
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 60
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 60
- 239000001301 oxygen Substances 0.000 title claims abstract description 60
- 239000011159 matrix material Substances 0.000 claims abstract description 25
- 239000002245 particle Substances 0.000 claims abstract description 11
- 239000004793 Polystyrene Substances 0.000 claims abstract description 7
- 229920002223 polystyrene Polymers 0.000 claims abstract description 7
- 239000003446 ligand Substances 0.000 claims abstract description 3
- 239000004372 Polyvinyl alcohol Substances 0.000 claims abstract 2
- 229920002451 polyvinyl alcohol Polymers 0.000 claims abstract 2
- 229920000036 polyvinylpyrrolidone Polymers 0.000 claims abstract 2
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims abstract 2
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims abstract 2
- 239000000975 dye Substances 0.000 claims description 27
- 238000000034 method Methods 0.000 claims description 22
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 239000000523 sample Substances 0.000 claims description 8
- 210000004027 cell Anatomy 0.000 claims description 6
- 244000005700 microbiome Species 0.000 claims description 6
- 238000001514 detection method Methods 0.000 claims description 5
- 238000006911 enzymatic reaction Methods 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 229920002338 polyhydroxyethylmethacrylate Polymers 0.000 claims description 3
- 239000012472 biological sample Substances 0.000 claims description 2
- 230000027734 detection of oxygen Effects 0.000 claims description 2
- 239000000017 hydrogel Substances 0.000 claims description 2
- 210000004962 mammalian cell Anatomy 0.000 claims description 2
- 125000004424 polypyridyl Polymers 0.000 claims description 2
- 125000005504 styryl group Chemical group 0.000 claims description 2
- 238000011002 quantification Methods 0.000 claims 4
- 229920001577 copolymer Polymers 0.000 claims 1
- 229920002635 polyurethane Polymers 0.000 claims 1
- 239000004814 polyurethane Substances 0.000 claims 1
- 229910052697 platinum Inorganic materials 0.000 abstract description 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 abstract 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 abstract 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 abstract 2
- DGEZNRSVGBDHLK-UHFFFAOYSA-N [1,10]phenanthroline Chemical compound C1=CN=C2C3=NC=CC=C3C=CC2=C1 DGEZNRSVGBDHLK-UHFFFAOYSA-N 0.000 abstract 1
- 239000007850 fluorescent dye Substances 0.000 abstract 1
- 229920001477 hydrophilic polymer Polymers 0.000 abstract 1
- 229910052763 palladium Inorganic materials 0.000 abstract 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 abstract 1
- 150000003303 ruthenium Chemical class 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 description 9
- 230000004044 response Effects 0.000 description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 8
- 239000007788 liquid Substances 0.000 description 8
- 238000005259 measurement Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- 238000004020 luminiscence type Methods 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- 238000000576 coating method Methods 0.000 description 6
- 230000035945 sensitivity Effects 0.000 description 6
- 230000008859 change Effects 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 4
- 230000003287 optical effect Effects 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 241001148470 aerobic bacillus Species 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000002209 hydrophobic effect Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 230000029058 respiratory gaseous exchange Effects 0.000 description 3
- 238000012216 screening Methods 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- 239000012085 test solution Substances 0.000 description 3
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- 102000008186 Collagen Human genes 0.000 description 2
- 108010035532 Collagen Proteins 0.000 description 2
- 102000016359 Fibronectins Human genes 0.000 description 2
- 108010067306 Fibronectins Proteins 0.000 description 2
- 108010039918 Polylysine Proteins 0.000 description 2
- 238000004113 cell culture Methods 0.000 description 2
- 229920001436 collagen Polymers 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010353 genetic engineering Methods 0.000 description 2
- 238000013537 high throughput screening Methods 0.000 description 2
- 230000005660 hydrophilic surface Effects 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 229920000656 polylysine Polymers 0.000 description 2
- 150000004032 porphyrins Chemical class 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000010791 quenching Methods 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- VJEVAXUMNMFKDT-UHFFFAOYSA-N 5,10,15,20-tetrakis(2,3,4,5,6-pentafluorophenyl)-21,23-dihydroporphyrin Chemical compound Fc1c(F)c(F)c(c(F)c1F)-c1c2ccc(n2)c(-c2c(F)c(F)c(F)c(F)c2F)c2ccc([nH]2)c(-c2c(F)c(F)c(F)c(F)c2F)c2ccc(n2)c(-c2c(F)c(F)c(F)c(F)c2F)c2ccc1[nH]2 VJEVAXUMNMFKDT-UHFFFAOYSA-N 0.000 description 1
- 102000004190 Enzymes Human genes 0.000 description 1
- 108090000790 Enzymes Proteins 0.000 description 1
- WPBUPFBTCDYKNM-UHFFFAOYSA-M [6-(diethylamino)-9-(2-octadecoxycarbonylphenyl)xanthen-3-ylidene]-diethylazanium;perchlorate Chemical compound [O-]Cl(=O)(=O)=O.CCCCCCCCCCCCCCCCCCOC(=O)C1=CC=CC=C1C1=C2C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C21 WPBUPFBTCDYKNM-UHFFFAOYSA-M 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000002210 biocatalytic effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 230000010261 cell growth Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000003891 environmental analysis Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 238000001917 fluorescence detection Methods 0.000 description 1
- 238000002875 fluorescence polarization Methods 0.000 description 1
- 238000002189 fluorescence spectrum Methods 0.000 description 1
- 230000012010 growth Effects 0.000 description 1
- 125000000623 heterocyclic group Chemical group 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000004060 metabolic process Effects 0.000 description 1
- 239000011859 microparticle Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- 230000036284 oxygen consumption Effects 0.000 description 1
- JZRYQZJSTWVBBD-UHFFFAOYSA-N pentaporphyrin i Chemical compound N1C(C=C2NC(=CC3=NC(=C4)C=C3)C=C2)=CC=C1C=C1C=CC4=N1 JZRYQZJSTWVBBD-UHFFFAOYSA-N 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- RKCAIXNGYQCCAL-UHFFFAOYSA-N porphin Chemical compound N1C(C=C2N=C(C=C3NC(=C4)C=C3)C=C2)=CC=C1C=C1C=CC4=N1 RKCAIXNGYQCCAL-UHFFFAOYSA-N 0.000 description 1
- 238000011165 process development Methods 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000005871 repellent Substances 0.000 description 1
- PYWVYCXTNDRMGF-UHFFFAOYSA-N rhodamine B Chemical compound [Cl-].C=12C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C2C=1C1=CC=CC=C1C(O)=O PYWVYCXTNDRMGF-UHFFFAOYSA-N 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/645—Specially adapted constructive features of fluorimeters
- G01N21/6452—Individual samples arranged in a regular 2D-array, e.g. multiwell plates
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
- G01N2021/6432—Quenching
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
- G01N2021/6439—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" with indicators, stains, dyes, tags, labels, marks
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
- G01N2021/6439—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" with indicators, stains, dyes, tags, labels, marks
- G01N2021/6441—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" with indicators, stains, dyes, tags, labels, marks with two or more labels
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/645—Specially adapted constructive features of fluorimeters
- G01N2021/6482—Sample cells, cuvettes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/27—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands using photo-electric detection ; circuits for computing concentration
- G01N21/274—Calibration, base line adjustment, drift correction
Definitions
- the invention relates to a new type of sensor that can be used to measure oxygen in microtiter plates or similar systems. With a new sensor principle, measurements can be made faster and it is less influenced by the surrounding medium.
- microtiter plates in various formats are used in a variety of ways.
- the associated microtiter plate readers are based on the measurement of absorption, flow resi nce time, flow reso nce time or fluorescence polarization. These methods tend to be very specific, which limits their application to selected systems. For this reason, alternatives have to be developed that are based on the sensors of widely applicable parameters such as oxygen.
- the measurement of the oxygen concentration as a biological parameter has been known for many years. Its importance lies not only in the field of screening processes, but also in medical diagnostics, environmental analysis and analytical chemistry. Monitoring the consumption of dissolved oxygen by microorganisms as a parameter for their metabolism has been investigated for many years. For example, C.E. Cliffcon 1937 measured the oxygen consumption of microorganisms over a period of several days using a Warburg bottle. This procedure measured the change in oxygen concentration in a slow and cumbersome manner.
- Clark electrode a newer electrochemical device, is also commonly used to measure dissolved oxygen.
- the Clark electrode consumes oxygen during use (thereby reducing the oxygen available to the microorganisms). Therefore, the electrode is typically only used to measure volumes of 100 ml or more to prevent the electrode from affecting the measurements.
- a “miniature” Clark electrode has been described, but this electrode is a complex, multi-component part that must also be in contact with the solution to be measured. While an oxygen permeable membrane can be used to prevent the electrode components of the device from interacting with the components of the test solution, the oxygen still has to balance between the test solution and the measuring system and is consumed as soon as it passes through the membrane.
- Optical systems that can provide oxygen concentration values have been developed to overcome the shortcomings of Clark's electrode systems.
- the main advantage of such optical methods is that the instruments required to determine the quantitative value itself have no physical contact with the test solution.
- Optical methods that allow both colorimetric and fluorometric oxygen analyzes, which can be carried out quickly and reproducibly, are known and the costs for such analyzes are often quite low.
- various methods of luminescence for determining oxygen have been described based on the ability of oxygen to quench the fluorescent or phosphorescent emission of a variety of compounds. However, such methods have not yet been adapted to the special needs of the screening.
- DE 3 346 810 C2 describes a sensor apparatus for determining the presence of oxygen in an environment which comprises luminescent material whose luminescence intensity and duration can be extinguished by oxygen, the luminescent material being built into a carrier material which is relatively permeable to oxygen and is relatively impermeable to annoying extinguishers.
- the apparatus requires a comparative indicator that is hermetically sealed against the oxygen to be determined.
- EP 0 509 791 B1 discloses a method and an apparatus for detecting the presence of breathing aerobic bacteria in a liquid. A decrease in the fluorescence intensity occurs under the influence of oxygen.
- the fluorescence sensor is in a matrix that is impermeable to water and non-gaseous solutes, however has a high permeability to oxygen.
- the presence of a non-water permeable matrix is necessary in order to reduce the influence of the sensor by components of the sample.
- this structure leads to major disadvantages.
- the water-impermeable matrix forms an oxygen reservoir, which can falsify the measurement result. Another disadvantage is the low sensitivity of the method.
- the sensitivity for the application described in EP 0 509 791 B1 is sufficient to detect the presence of breathing aerobic bacteria in a liquid, since at the beginning there is a solution saturated with oxygen, the oxygen concentration of which then decreases sharply in order to increase a plateau at a lower value reach, so that large differences in the oxygen concentrations can be detected.
- mammalian cells for example, consume much less oxygen, so that the small changes in oxygen concentration that can be achieved require a method that has a significantly higher sensitivity.
- the water-impermeable matrix of the fluorescence sensor must be in equilibrium with the liquid surrounding it before it can show a change in the signal due to the change in the oxygen content of the liquid.
- the present application relates to a device for the detection of oxygen according to claim 1.
- Preferred embodiments of this device are the subject of dependent claims 2 to 13.
- the device can be used to detect oxygen in a sample, in particular in a biological sample, for example in a culture of microorganisms or higher cells or in the case of enzymatic reactions.
- a preferred embodiment of the optical oxygen sensor in the device according to the invention consists of the following components: a luminescent dye, the phosphorescence of which is quenched by oxygen in the sample. This dye is enclosed in small polymer particles (with diameters from a few nm to a few ⁇ m). The material of these particles is characterized by the fact that it has water-repellent properties. This ensures that the built-in water-insoluble dye is not washed out by proteins.
- the individual oxygen-sensitive nano- or microparticle is already a completely shielded sensor.
- Cross-sensitivities caused by water or other substances dissolved in the water are essentially excluded. It is therefore not necessary to enclose the particles in a hydrophobic matrix, which ensures the shielding of the luminescence sensor. This means that the particles can be installed in any layer, which is also permeable to water.
- the response time of the sensors is significantly reduced. Response times in the range of seconds are possible. This is due to the fact that on the one hand the sensor layer is not a crucial oxygen reservoir, and on the other hand the same reactions can take place in the swollen matrix as in the protruding sample.
- Linear ethanol-soluble hydrogels can be used as the incorporation matrix. This considerably simplifies the process of manufacturing the microtiter plates. The matrix does not need to be crosslinked, and cleavage products do not have to be removed from the sensors by complex washing procedures. This shortens the manufacturing process considerably and reduces production costs.
- the device according to the invention comprises an additional coating from solutions of e.g. Polylysine, fibronectin and / or collagen, e.g. to improve cell growth.
- solutions of e.g. Polylysine, fibronectin and / or collagen e.g. to improve cell growth.
- the device may comprise two or more spectrally different luminescent dyes.
- One dye can be designed as an indicator, while another serves as a reference dye.
- two spectrally different dyes are used, the first being oxygen-sensitive and the second being essentially oxygen-sensitive in comparison to the first.
- the oxygen sensitivities should differ measurably from one another, where, under conditions of use, the sensitivity of the indicator dye is higher than that of the reference dye, for example by a factor> 10, preferably> 100, more preferably> 1000.
- the second dye is preferably selected from the group consisting of rhodamines, xanthenoids, styryl dyes and merocyanines.
- the first dye can preferably be selected from the group consisting of Pt (II) porphyrins, Pd (II) porphyrins and Ru (II) complexes with poly-N heterocycle, for example polypyridyl ligands.
- Two luminescences are read out for signal acquisition. The signal is the quotient of the two luminescence intensities or decay times. An internally referenced signal is obtained.
- the reference dye does not have to be included in the first matrix, but can also be present outside. In some applications, such a measurement with two luminophores can be advantageous, since greater accuracy can be achieved, since time fluctuations in the light intensity of the light source used and time fluctuations in the sensitivity of the readout unit used are largely referenced and non-wavelength-dependent superimpositions of the sensor signal Self-luminescence of the sample can be largely referenced.
- the two dyes can be mixed in a constant ratio during production, so that the resulting signal is independent of the amount of dye mixture used, which allows greater tolerances in the coating of the absolute amount of sensor used. Due to the larger tolerance allowed during production, smaller amounts of substance can be used for the coating.
- a Manufacturing instructions for oxygen-sensitive particles :
- the cocktail described in B2) contains a rhodamine reference dye.
- 96'Well format 1.5 ⁇ l of the cocktail described under B1) and B2) are dispersed in each well of the MPT. After evaporation of the solvent, the plate can be y-sterilized.
- Figure 1 shows a fluorescence spectrum of a sensor according to the invention, oxygen-free or air-saturated. From Fig. 1 it can be seen that the intensity of the fluorescence decreases considerably due to saturation with air. (Excitation: 540 nm)
- Figure 2 illustrates the response time of a sensor according to the invention as a function of the air saturation [%]. Even at low air contents, the sensor according to the invention shows a comparatively short response time.
- Figure 3 shows the comparison of the oxygen signal for a sensor (1) according to the invention and a sensor according to EP 0 509 791 B1 (2). It can be seen that the sensor according to the invention has a significantly shorter response time.
Abstract
The invention relates to a novel sensor type that uses microtiter plates or similar supports containing depressions for receiving samples to measure oxygen. Said depressions contain luminescent or fluorescent dyes (for example platinum, palladium or ruthenium complexes with phenanthroline, porphyrine or pyridine ligands) which are embedded in particles of a gas-permeable but water-impermeable matrix, said matrix being a polystyrene derivative or a polystyrene copolymer. The particles, for their part, are dispersed in a second, water-permeable matrix that consists of a hydrophilic polymer, such as for example polyhydroxymethacrylate, polyvinyl alcohol or polyvinylpyrrolidone.
Description
SAUERSTOFFSENSOREN AUF MIKROTITERP ATTEOXYGEN SENSORS ON MICROTITER P ATTE
Beschreibungdescription
Die Erfindung bezieht sich auf einen neuen Sensortyp, der benutzt werden kann, um Sauerstoff in Mikrotiterplatten oder ähnlichen Systemen zu messen. Mit einem neuen Sensorprinzip kann schneller gemessen werden und es ist weniger von dem umgebenden Medium beeinflusst.The invention relates to a new type of sensor that can be used to measure oxygen in microtiter plates or similar systems. With a new sensor principle, measurements can be made faster and it is less influenced by the surrounding medium.
Die Produktion von Feinchemikalien ist normalerweise mit einem Verbrauch an Rohmaterial verbunden, der signifikant über der stöchiometrisch notwendigen Menge liegt. Biokatalytische Prozesse stellen Wege zur Verfügung, weniger Substrat zu verbrauchen und weniger Nebenprodukte zu bilden. Diese ressourcenschonenede Vorgehensweise schützt unsere Umwelt.The production of fine chemicals is usually associated with a consumption of raw material that is significantly above the stoichiometrically necessary amount. Biocatalytic processes provide ways of using less substrate and less by-products. This resource-saving approach protects our environment.
Um dieses Potential vollständig auszunutzen und somit einen ökonomisch und ökologisch wettbewerbsfähigen Prozess darzustellen, muss die Prozessentwicklung nachhaltig beschleunigt werden. Der Kernpunkt dieser Prozesse ist die Biokatalyse. Während moderne genetische Verfahren {Genetic Engineering) , wie error-phone PCR die schnelle Erzeugung von Enzymvariationen in Größenordnungen von 104 bis 106 Varianten erlauben, stellen die Screening-Verfahren die Engstelle im Entwicklungsprozess dar.In order to fully exploit this potential and thus represent an economically and ecologically competitive process, process development must be accelerated sustainably. The core of these processes is biocatalysis. While modern genetic engineering (genetic engineering), such as error-phone PCR, allows the rapid generation of enzyme variations in the order of 10 4 to 10 6 variants, the screening methods represent the bottleneck in the development process.
Das Verlangen nach chemischen Verbindungen, die spezifisch an biologische Zellen binden, hat die Entwicklung von Hochdurchsatzverfahren (high-throughput screening, HTS) bewirkt. Mikrotiterplatten in verschiedenen Formaten sind dabei in vielfältigem Einsatz. Die zugehörigen Mikrotiterplatten-Auslesegeräte basieren auf der Messung von Absorption, F l u o resze n zi nte n s ität, F l u o reszen za b kl i n g zeit o d er/u n d Fluoreszenzpolarisation.
Diese Methoden neigen dazu, sehr spezifisch zu sein, was ihre Anwendung auf ausgewählte Systeme beschränkt. Aus diesem Grund müssen Alternativen entwickelt werden, die auf der Sensorik breit anwendbarer Parameter wie dem Sauerstoff basieren.The desire for chemical compounds that bind specifically to biological cells has led to the development of high-throughput screening (HTS). Microtiter plates in various formats are used in a variety of ways. The associated microtiter plate readers are based on the measurement of absorption, flow resi nce time, flow reso nce time or fluorescence polarization. These methods tend to be very specific, which limits their application to selected systems. For this reason, alternatives have to be developed that are based on the sensors of widely applicable parameters such as oxygen.
Die Messung der Sauerstoff konzentration als biologischer Parameter ist seit vielen Jahren bekannt. Seine Bedeutung liegt dabei nicht nur im Bereich der Screeningprozesse, sondern auch in der medizinischen Diagnostik, der Umweltanalytik und der analytischen Chemie. So ist Überwachung des Verbrauchs von gelöstem Sauerstoff durch Mikroorganismen als ein Kennwert für deren Stoffwechsel seit vielen Jahren untersucht worden. Zum Beispiel überwachte C.E. Cliffcon 1937 den Sauerstoffverbrauch von Mikroorganismen während eines Zeitraums von mehreren Tagen unter Verwendung einer Warburg-Flasche. Dieses Verfahren maß die Veränderung der Sauerstoff konzentration in einer langsamen und schwerfälligen Weise.The measurement of the oxygen concentration as a biological parameter has been known for many years. Its importance lies not only in the field of screening processes, but also in medical diagnostics, environmental analysis and analytical chemistry. Monitoring the consumption of dissolved oxygen by microorganisms as a parameter for their metabolism has been investigated for many years. For example, C.E. Cliffcon 1937 measured the oxygen consumption of microorganisms over a period of several days using a Warburg bottle. This procedure measured the change in oxygen concentration in a slow and cumbersome manner.
Die "Clark-Elektrode", ein neueres elektrochemisches Gerät, wird ebenfalls gewöhnlich zur Messung von gelöstem Sauerstoff verwendet. Unglücklicherweise verbraucht die Clark-Elektrode während des Gebrauchs Sauerstoff (wodurch sie den den Mikroorganismen zur Verfügung stehenden Sauerstoff vermindert). Daher wird die Elektrode typischerweise lediglich zur Messung von Volumina von 100 ml oder mehr verwendet, um zu verhindern, dass die Elektrode die Messungen beeinflusst.The "Clark electrode", a newer electrochemical device, is also commonly used to measure dissolved oxygen. Unfortunately, the Clark electrode consumes oxygen during use (thereby reducing the oxygen available to the microorganisms). Therefore, the electrode is typically only used to measure volumes of 100 ml or more to prevent the electrode from affecting the measurements.
Eine "Miniatur"-Clark-Elektrode wurde beschrieben, aber diese Elektrode ist ein kompliziertes Mehrkomponententeil, das ebenfalls mit der zu messenden Lösung in Berührung stehen muss. Während eine sauerstoffdurchlässige Membran verwendet werden kann, um die Wechselwirkung der Elektrodenkomponenten des Geräts mit den Bestandteilen der Prüflösung zu verhindern, muss der Sauerstoff noch
zwischen der Prüflösung und dem Messsystem ins Gleichgewicht kommen und wird verbraucht, sobald er die Membran passiert.A "miniature" Clark electrode has been described, but this electrode is a complex, multi-component part that must also be in contact with the solution to be measured. While an oxygen permeable membrane can be used to prevent the electrode components of the device from interacting with the components of the test solution, the oxygen still has to balance between the test solution and the measuring system and is consumed as soon as it passes through the membrane.
Optische Systeme, die Werte für die Sauerstoffkonzentration liefern können, wurden entwickelt, um die Unzulänglichkeiten der Clark- Elektrodensysteme zu überwinden. Der Hauptvorteil derartiger optischer Verfahren besteht darin, dass das zur Bestimmung des quantitativen Wertes erforderliche Instrumentarium selbst keine physikalische Berührung mit der Prüflösung hat. Optische Verfahren, die sowohl kolorimetrische als auch fluorometrische Sauerstoffanalysen erlauben, die schnell und reproduzierbar auszuführen sind, sind bekannt und die Kosten für derartige Analysen sind oft ziemlich niedrig. Zum Beispiel wurden verschiedene Lumineszenzverfahren zur Bestimmung von Sauerstoff beschrieben, die auf der Fähigkeit von Sauerstoff beruhen, die Fluoreszenz- oder Phosphoreszenzemission einer Vielzahl von Verbindungen zu löschen. Jedoch wurden derartige Verfahren bisher nicht auf die speziellen Bedürfnisses des Screenings angepasst.Optical systems that can provide oxygen concentration values have been developed to overcome the shortcomings of Clark's electrode systems. The main advantage of such optical methods is that the instruments required to determine the quantitative value itself have no physical contact with the test solution. Optical methods that allow both colorimetric and fluorometric oxygen analyzes, which can be carried out quickly and reproducibly, are known and the costs for such analyzes are often quite low. For example, various methods of luminescence for determining oxygen have been described based on the ability of oxygen to quench the fluorescent or phosphorescent emission of a variety of compounds. However, such methods have not yet been adapted to the special needs of the screening.
DE 3 346 810 C2 beschreibt eine Sensorapparatur zur Bestimmung der Anwesenheit von Sauerstoff in einer Umgebung, die lumineszierendes Material umfasst, dessen Lumineszenzintensität und -dauer durch Sauerstoff gelöscht werden kann, wobei das lumineszierende Material in ein Trägermaterial eingebaut ist, das relativ durchlässig für Sauerstoff und relativ undurchlässig für störende Löscher ist. Zusätzlich bedarf die Apparatur eines Vergleichsindikators, der hermetisch gegen den zu bestimmenden Sauerstoff abgeschlossen ist.DE 3 346 810 C2 describes a sensor apparatus for determining the presence of oxygen in an environment which comprises luminescent material whose luminescence intensity and duration can be extinguished by oxygen, the luminescent material being built into a carrier material which is relatively permeable to oxygen and is relatively impermeable to annoying extinguishers. In addition, the apparatus requires a comparative indicator that is hermetically sealed against the oxygen to be determined.
Aus EP 0 509 791 B1 ist ein Verfahren und eine Apparatur zum Nachweis der Anwesenheit von atmenden aeroben Bakterien in einer Flüssigkeit bekannt. Dabei tritt unter Einwirkung von Sauerstoff eine Verminderung der Fluoreszenzintensität auf. Der Fluoreszenzsensor liegt in einer Matrix vor, die für Wasser und nichtgasförmige gelöste Stoffe undurchlässig ist, aber
eine große Durchlässigkeit für Sauerstoff aufweist. Das Vorhandensein einer nichtwasserdurchlässigen Matrix ist notwendig, um die Beeinflussung des Sensors durch Bestandteile der Probe zu verringern. Dieser Aufbau führt jedoch zu großen Nachteilen. Einmal bildet die wasserundurchlässige Matrix ein Sauerstoffreservoir, welches das Messergebnis verfälschen kann. Ein weiterer Nachteil ist die geringe Sensitivität der Methode. Zwar ist die Sensitivität für die in EP 0 509 791 B1 beschriebene Anwendung zum Nachweis der Anwesenheit von atmenden aeroben Bakterien in einer Flüssigkeit ausreichend, da zu Beginn eine mit Sauerstoff gesättigte Lösung vorliegt, deren Sauerstoffkonzentration dann stark abnimmt, um ein Plateau bei geringerem Wert zu erreichen, so dass große Unterschiede in den Sauerstoff konzentrationen detektierbar sind. Beispielsweise Säugerzellen verbrauchen jedoch viel weniger Sauerstoff, so dass dort die zu erzielenden kleinen Änderungen der Sauerstoffkonzentration eine Methode verlangen, die eine signifikant höhere Sensitivität hat. Zum anderen muss sich die wasserundurchlässige Matrix des Fluoreszenzsensors mit der sie umgebenden Flüssigkeit im Gleichgewicht befinden, bevor sie eine Änderung des Signals aufgrund der Änderung des Sauerstoffgehalts der Flüssigkeit zeigen kann. An der Grenzfläche der wasserundurchlässigen Matrix zur sie umgebenden Flüssigkeit besteht aber ein zusätzliches Gleichgewicht, welches sich erst zeitverzögert einstellt. Dadurch erhält man eine lange Ansprechzeit. Die in EP 0 509 791 B1 beschriebene Anwendung zum Nachweis der Anwesenheit von atmenden aeroben Bakterien in einer Flüssigkeit beobachtet verhältnismäßig langsame Prozesse, wobei die zu erzielende Ansprechzeit ausreichend ist. Beispielsweise enzymatische Umsetzungen führen jedoch zu einer sehr schnellen Änderung der Sauerstoffmenge in der den Sensor umgebenden Flüssigkeit. Dabei kann sich die Sauerstoffkonzentration von 100 % Luftsättigung auf 0 % Luftsättigung innerhalb von unter einer Minute ändern. Solche schnellen Prozesse können mit dem in EP 0 509 791 B1 beschriebenen Sensor nicht detektiert werden.
Es ist daher eine Aufgabe der Erfindung, eine verbesserte Vorrichtung zum Nachweis von Sauerstoff, insbesondere als Mikrotiterplatte oder Kulturplatte mit integrierter Sensorik, bereitzustellen. Es ist weiterhin eine Aufgabe dieser Erfindung, die Messung der Sauerstoffkonzentration in dieser Vorrichtung zu ermöglichen, ohne dass der eingesetzte Sensor ein störendes Sauerstoffreservoir darstellt. Ebenfalls ist es Aufgabe dieser Erfindung, den Sauerstoffgehalt mit geringer Zeitverzögerung (kleine Ansprechzeit), nominell 5 Minuten oder weniger, zu bestimmen. Darüber hinaus ist es Aufgabe der Erfindung, die Detektion schneller Änderungen der Sauerstoffkonzentration zu bestimmen.EP 0 509 791 B1 discloses a method and an apparatus for detecting the presence of breathing aerobic bacteria in a liquid. A decrease in the fluorescence intensity occurs under the influence of oxygen. The fluorescence sensor is in a matrix that is impermeable to water and non-gaseous solutes, however has a high permeability to oxygen. The presence of a non-water permeable matrix is necessary in order to reduce the influence of the sensor by components of the sample. However, this structure leads to major disadvantages. On the one hand, the water-impermeable matrix forms an oxygen reservoir, which can falsify the measurement result. Another disadvantage is the low sensitivity of the method. The sensitivity for the application described in EP 0 509 791 B1 is sufficient to detect the presence of breathing aerobic bacteria in a liquid, since at the beginning there is a solution saturated with oxygen, the oxygen concentration of which then decreases sharply in order to increase a plateau at a lower value reach, so that large differences in the oxygen concentrations can be detected. However, mammalian cells, for example, consume much less oxygen, so that the small changes in oxygen concentration that can be achieved require a method that has a significantly higher sensitivity. On the other hand, the water-impermeable matrix of the fluorescence sensor must be in equilibrium with the liquid surrounding it before it can show a change in the signal due to the change in the oxygen content of the liquid. However, there is an additional equilibrium at the interface of the water-impermeable matrix with the liquid surrounding it, which is only delayed. This gives you a long response time. The application described in EP 0 509 791 B1 for detecting the presence of breathing aerobic bacteria in a liquid observes relatively slow processes, the response time to be achieved being sufficient. For example, enzymatic reactions, however, lead to a very rapid change in the amount of oxygen in the liquid surrounding the sensor. The oxygen concentration can change from 100% air saturation to 0% air saturation within less than a minute. Such rapid processes cannot be detected with the sensor described in EP 0 509 791 B1. It is therefore an object of the invention to provide an improved device for detecting oxygen, in particular as a microtiter plate or culture plate with integrated sensors. It is a further object of this invention to enable the measurement of the oxygen concentration in this device without the sensor used being a disruptive oxygen reservoir. It is also an object of this invention to determine the oxygen content with a short time delay (short response time), nominally 5 minutes or less. In addition, it is an object of the invention to determine the detection of rapid changes in the oxygen concentration.
Die vorstehend erwähnten und verwandten Aufgaben werden durch das Verfahren und die Vorrichtung der Erfindung verwirklicht. Diese Verfahren und Vorrichtungen verwenden ein Fluoreszenznachweissystem, in dem die fluoreszierende Sensor-Verbindung einen quantifizierbaren Grad der Löschung zeigt, wenn sie Sauerstoff ausgesetzt wird. Spezielle Vorteile werden durch den Einsatz einer hydrophilen Matrix erreicht. Dadurch kann der flüssige Anteil einer Probe zum größten Teil die Sensormatrix durchdringen. Somit stellt die Sensormatrix kein störendes Sauerstoffreservoir dar. Der Sensor steht dadurch in engerem Kontakt zur Probe und kann somit eine Messung mit geringer Ansprechzeit gewährleisten.The aforementioned and related objects are accomplished by the method and apparatus of the invention. These methods and devices use a fluorescence detection system in which the fluorescent sensor compound exhibits a quantifiable degree of quenching when exposed to oxygen. Special advantages are achieved through the use of a hydrophilic matrix. As a result, the liquid portion of a sample can largely penetrate the sensor matrix. The sensor matrix therefore does not represent a disturbing oxygen reservoir. The sensor is therefore in closer contact with the sample and can therefore ensure a measurement with a short response time.
Ein Gegenstand der vorliegenden Anmeldung ist eine Vorrichtung zum Nachweis von Sauerstoff gemäß Anspruch 1 . Bevorzugte Ausführungsformen dieser Vorrichtung sind Gegenstand der Unteransprüche 2 bis 13.The present application relates to a device for the detection of oxygen according to claim 1. Preferred embodiments of this device are the subject of dependent claims 2 to 13.
Die Vorrichtung kann zum Nachweis von Sauerstoff in einer Probe, insbesondere in einer biologischen Probe, verwendet werden, beispielsweise in einer Kultur von Mikroorganismen oder höheren Zellen oder bei enzymatischen Umsetzungen.
Eine bevorzugte Ausführungsform des optischen Sauerstoffsensors in der erfindungsgemäßen Vorrichtung besteht aus folgenden Komponenten: einem lumineszierenden Farbstoff, dessen Phosphoreszenz durch in der Probe befindlichen Sauerstoff gelöscht wird. Dieser Farbstoff ist eingeschlossen in kleinen Polymerpartikeln (mit Durchmessern von wenigen nm bis zu einigen μm). Das Material dieser Partikel ist dadurch gekennzeichnet, dass es wasserabweisende Eigenschaften besitzt. Damit wird sichergestellt, dass der eingebaute wasserunlösliche Farbstoff durch Proteine nicht ausgewaschen wird. Im Gegensatz zu anderen Vorrichtungen (z.B. EP 0 509 791 B1 ), in welchen der sauerstoffempfindliche Farbstoff sich innerhalb einer hydrophoben Matrix befindet, ist das einzelne sauerstoffempfindliche Nano- oder Mikropartikel bereits ein vollständig abgeschirmter Sensor. Querempfindlichkeiten durch Wasser oder andere im Wasser gelöste Stoffe sind damit im Wesentlichen ausgeschlossen. Damit ist es nicht notwendig, die Partikel in eine hydrophobe Matrix einzuschließen, die für die Abschirmung des Lumineszenzsensors sorgt. Damit können die Partikel in jede beliebige, und damit auch wasserdurchlässige, Schicht eingebaut werden.The device can be used to detect oxygen in a sample, in particular in a biological sample, for example in a culture of microorganisms or higher cells or in the case of enzymatic reactions. A preferred embodiment of the optical oxygen sensor in the device according to the invention consists of the following components: a luminescent dye, the phosphorescence of which is quenched by oxygen in the sample. This dye is enclosed in small polymer particles (with diameters from a few nm to a few μm). The material of these particles is characterized by the fact that it has water-repellent properties. This ensures that the built-in water-insoluble dye is not washed out by proteins. In contrast to other devices (eg EP 0 509 791 B1) in which the oxygen-sensitive dye is located within a hydrophobic matrix, the individual oxygen-sensitive nano- or microparticle is already a completely shielded sensor. Cross-sensitivities caused by water or other substances dissolved in the water are essentially excluded. It is therefore not necessary to enclose the particles in a hydrophobic matrix, which ensures the shielding of the luminescence sensor. This means that the particles can be installed in any layer, which is also permeable to water.
Der Einbau in eine solche wasseraufnehmende, quellende Matrix hat im Vergleich zu den Vorrichtungen mit hydrophober Matrix folgende Vorteile:Installation in such a water-absorbing, swelling matrix has the following advantages compared to the devices with a hydrophobic matrix:
1 . Die Ansprechzeit der Sensoren wird entscheidend verkürzt. Ansprechzeiten im Sekundenbereich sind möglich. Dies ist darauf zurückzuführen, dass zum einen die Sensorschicht kein entscheidendes Sauerstoffreservoir ist, und zum zweiten in der gequollenen Matrix die gleichen Reaktionen ablaufen könen wie in der überstehenden Probe.1 . The response time of the sensors is significantly reduced. Response times in the range of seconds are possible. This is due to the fact that on the one hand the sensor layer is not a crucial oxygen reservoir, and on the other hand the same reactions can take place in the swollen matrix as in the protruding sample.
2. Durch die hydrophilen Eigenschaften des Sensors eignet sich der Sensor gut zur Zellkultivierung. Im Gegensatz dazu eignet sich eine Vorrichtung gemäß EP 0 509 791 B1 durch ihre Hydrophophie nur
schlecht zur Zellkultivierung. Gründe dafür sind z.B., dass adhärent wachsende Zellen für ihr Wachstum hydrophile Oberflächen bevorzugen. Ausserdem werden für anspruchsvolle Zellen zusätzliche Beschichtungen aus Lösungen von beispielsweise Polylysin, Fibronectin oder Kollagen verwendet. Die Herstellung solcher Beschichtungen gelingt bevorzugt auf hydrophilen Oberflächen.2. Due to the hydrophilic properties of the sensor, the sensor is well suited for cell cultivation. In contrast, a device according to EP 0 509 791 B1 is only suitable due to its hydrophobicity bad for cell cultivation. Reasons for this are, for example, that adherently growing cells prefer hydrophilic surfaces for their growth. In addition, additional coatings from solutions of, for example, polylysine, fibronectin or collagen are used for demanding cells. Such coatings are preferably produced on hydrophilic surfaces.
3. Es können lineare Ethanol-Iösliche Hydrogele als Einbaumatrix verwendet werden. Damit vereinfacht sich der Herstellungsprozess der Mikrotiterplatten erheblich. Es braucht keine Vernetzung der Matrix stattfinden, und Abspaltungsprodukte brauchen nicht durch aufwendige Waschprozeduren aus den Sensoren entfernt zu werden. Damit verkürzt sich der Herstellungsprozess beträchtlich und die Produktionskosten werden gesenkt.3. Linear ethanol-soluble hydrogels can be used as the incorporation matrix. This considerably simplifies the process of manufacturing the microtiter plates. The matrix does not need to be crosslinked, and cleavage products do not have to be removed from the sensors by complex washing procedures. This shortens the manufacturing process considerably and reduces production costs.
In noch einer weiteren Ausführungsform umfasst die Vorrichtung gemäß der Erfindung eine zusätzliche Beschichtung aus Lösungen von z.B. Polylysin, Fibronectin oder/und Kollagen, z.B. zur Verbesserung des Zellwachstums.In yet another embodiment, the device according to the invention comprises an additional coating from solutions of e.g. Polylysine, fibronectin and / or collagen, e.g. to improve cell growth.
In noch einer weiteren Ausführungsform der Erfindung kann die Vo rrichtu ng zwei oder mehr spektral unterschied liche Lumineszenzfarbstoffe umfassen. Dabei kann ein Farbstoff als Indikator ausgeführt sein, während ein anderer als Referenzfarbstoff dient. Insbesondere werden zwei spektral unterschiedliche Farbstoffe verwendet, wobei der erste sauerstoffsensitiv und der zweite im Vergleich zum ersten im Wesentlichen sauerstoffinsensitiv ist. Die Sauerstoffsensitivitäten sollten sich messbar voneinander unterscheiden , wo bei unter Anwendungsbedingungen die Sensitivität des Indikator-Farbstoffes beispielsweise um den Faktor > 10, vorzugsweise > 100, noch mehr bevorzugt > 1000 höher ist als diejenige des Referenzfarbstoffs.
Vorzugsweise wird der zweite Farbstoff ausgewählt aus der Gruppe bestehend aus Rhodaminen, Xanthenoiden, Styrylfarbstoffen und Merocyaninen. Der erste Farbstoff kann vorzugsweise ausgewählt sein aus der Gruppe bestehend aus Pt-(ll)-porphyrinen, Pd-(ll)-porphyrinen und Ru- (Il)-Komplexen mit Poly-N-Heterocyclus, z.B. Polypyridyl-Liganden. Zur Signalerfassung werden zwei Lumineszenzen ausgelesen. Das Signal ist dabei der Quotient aus beiden Lumineszenzintensitäten oder -abklingzeiten. Man erhält ein intern referenziertes Signal.In yet another embodiment of the invention, the device may comprise two or more spectrally different luminescent dyes. One dye can be designed as an indicator, while another serves as a reference dye. In particular, two spectrally different dyes are used, the first being oxygen-sensitive and the second being essentially oxygen-sensitive in comparison to the first. The oxygen sensitivities should differ measurably from one another, where, under conditions of use, the sensitivity of the indicator dye is higher than that of the reference dye, for example by a factor> 10, preferably> 100, more preferably> 1000. The second dye is preferably selected from the group consisting of rhodamines, xanthenoids, styryl dyes and merocyanines. The first dye can preferably be selected from the group consisting of Pt (II) porphyrins, Pd (II) porphyrins and Ru (II) complexes with poly-N heterocycle, for example polypyridyl ligands. Two luminescences are read out for signal acquisition. The signal is the quotient of the two luminescence intensities or decay times. An internally referenced signal is obtained.
Der Referenzfarbstoff muss nicht in der ersten Matrix eingeschlossen sein, sondern kann auch ausserhalb vorliegen. In manchen Anwendungen kann eine solche Messung mit zwei Luminophoren von Vorteil sein, da eine höhere Genauigkeit erreicht werden kann, da zeitliche Schwankungen der Lichtintensität der verwendeten Lichtquelle sowie zeitliche Schwankungen der Sensitivität der verwendeten Ausleseeinheit zum großen Teil referenziert werden und nicht wellenlängenabhängige Überlagerungen des Sensorsignals mit Eigenlumineszenz der Probe zum großen Teil referenziert werden können.The reference dye does not have to be included in the first matrix, but can also be present outside. In some applications, such a measurement with two luminophores can be advantageous, since greater accuracy can be achieved, since time fluctuations in the light intensity of the light source used and time fluctuations in the sensitivity of the readout unit used are largely referenced and non-wavelength-dependent superimpositions of the sensor signal Self-luminescence of the sample can be largely referenced.
Weiterhin können die beiden Farbstoffe bei der Herstellung in einem konstanten Verhältnis vermischt werden, so dass das resultierende Signal unabhängig von der eingesetzten Menge des Farbstoffgemisches ist, was größere Toleranzen bei der Beschichtung der eingesetzten absoluten Menge Sensor erlaubt. Durch die größere bei der Herstellung erlaubte Toleranz können geringere Substanzmengen für die Beschichtung verwendet werden.Furthermore, the two dyes can be mixed in a constant ratio during production, so that the resulting signal is independent of the amount of dye mixture used, which allows greater tolerances in the coating of the absolute amount of sensor used. Due to the larger tolerance allowed during production, smaller amounts of substance can be used for the coating.
In dieser Ausführungsform der erfindungsgemäßen Vorrichtung kann auch die Messung nur der Lumineszenzintensität oder -abklingzeit des Indikator- Farbstoffes erfolgen.
Herstellungsbeispiel für Mikrotiterplatten mit hydrophilen Sauerstoff optodenIn this embodiment of the device according to the invention, only the luminescence intensity or decay time of the indicator dye can be measured. Production example for microtiter plates with hydrophilic oxygen optodes
A Herstellungsvorschrift sauerstoffsensitiver Partikel:A Manufacturing instructions for oxygen-sensitive particles:
1 ml einer 10 % (w/w) Polystyrol-Suspension (Aldrich, 45,948-8) wird mit 3 ml Wasser und 1 ml Methanol versetzt und 1 h gerührt. Dazu werden 200 μl einer Lösung von 0, 1 mg Pt(ll)meso-tetra(pentafluorphenyl)porphin (Porphin Products, Pt T975) in Chloroform versetzt und 24 h gerührt. Die Partikel werden abzentrifugiert, mehrmals mit Ethanol gewaschen und in 1 ml Ethanol resuspendiert.1 ml of a 10% (w / w) polystyrene suspension (Aldrich, 45,948-8) is mixed with 3 ml of water and 1 ml of methanol and stirred for 1 hour. 200 μl of a solution of 0.1 mg of Pt (II) mesotetra (pentafluorophenyl) porphine (Porphin Products, Pt T975) in chloroform are added and the mixture is stirred for 24 h. The particles are centrifuged off, washed several times with ethanol and resuspended in 1 ml of ethanol.
B Herstellungsvorschrift O2-Cocktails:B Manufacturing instructions for O 2 cocktails:
1 ) 500 mg Polyhydroxyethylmethacrylat (PolyHema, Polysciences, 09689) werden in 10 ml Ethanol und 100 μ\ Wasser gelöst. Zu dieser Lösung wird 1 ml der unter A beschriebenen Suspension gegeben und 12 h gerührt.1) 500 mg of polyhydroxyethyl methacrylate (PolyHema, Polysciences, 09689) are dissolved in 10 ml of ethanol and 100 μ \ water. 1 ml of the suspension described under A is added to this solution and stirred for 12 h.
2) 500 mg Polyhydroxyethylmethacrylat (PolyHema, Polysciences, 06989I und 0.1 mg Rhodamin-B-octadecylesterperchlorat (Fluka,2) 500 mg polyhydroxyethyl methacrylate (PolyHema, Polysciences, 06989I and 0.1 mg rhodamine-B-octadecyl ester perchlorate (Fluka,
83685) werden in 10 ml Ethanol und 100 μ\ Wasser gelöst. Zu dieser Lösung wird 1 ml der unter A beschriebenen Suspension gegeben und 12 h gerührt.83685) are dissolved in 10 ml ethanol and 100 μ \ water. 1 ml of the suspension described under A is added to this solution and stirred for 12 h.
Der in B2) beschriebene Cocktail enthält zusätzlich zu dem hydrophob verkapselten Porphin-Farbstoff einen Rhodamin Referenzfarbstoff.In addition to the hydrophobically encapsulated porphine dye, the cocktail described in B2) contains a rhodamine reference dye.
C Vorschrift zur Beschichtung von Mikrotiterplatten (MTP) mit Sauerstoff Sensoren:C Regulation for the coating of microtiter plates (MTP) with oxygen sensors:
96'Well Format:
ln jedes Well der MPT werden 1 ,5 μ\ des unter B1 ) bzw. B2) beschriebenen Cocktails dispergiert. Nach dem Verdampfen des Lösungsmittels kann die Platte y-sterilisiert werden.96'Well format: 1.5 μl of the cocktail described under B1) and B2) are dispersed in each well of the MPT. After evaporation of the solvent, the plate can be y-sterilized.
Durch die Abbildungen wird die Erfindung näher erläutert.The invention is explained in more detail by the figures.
Abbildung 1 zeigt ein Fluoreszenzspektrum eines erfindungsgemäßen Sensors, sauerstofffrei bzw. Luft-gesättigt. Aus Abb. 1 ist ersichtlich, dass die Intensität der Fluoreszenz durch eine Sättigung mit Luft beträchtlich abnimmt. (Anregung: 540 nm)Figure 1 shows a fluorescence spectrum of a sensor according to the invention, oxygen-free or air-saturated. From Fig. 1 it can be seen that the intensity of the fluorescence decreases considerably due to saturation with air. (Excitation: 540 nm)
Abbildung 2 veranschaulicht die Ansprechzeit eines erfindungsgemäßen Sensors in Abhängigkeit von der Luftsättigung [%]. Auch bei geringen Luftgehalten zeigt der erfindungsgemäße Sensor eine vergleichsweise geringe Ansprechzeit.Figure 2 illustrates the response time of a sensor according to the invention as a function of the air saturation [%]. Even at low air contents, the sensor according to the invention shows a comparatively short response time.
In Abbildung 3 ist der Vergleich des Sauerstoffsignals bei einem erfindungsgemäßen Sensor (1 ) und einem Sensor gemäß EP 0 509 791 B1 (2) gezeigt. Es ist ersichtlich, dass der erfindungsgemäße Sensor eine wesentlich geringere Ansprechzeit aufweist.
Figure 3 shows the comparison of the oxygen signal for a sensor (1) according to the invention and a sensor according to EP 0 509 791 B1 (2). It can be seen that the sensor according to the invention has a significantly shorter response time.
Claims
1 . Vorrichtung zum Nachweis von Sauerstoff umfassend: einen Träger mit mehreren Vertiefungen zur Probenaufnahme, wobei in den Vertiefungen Sauerstoffsensoren vorgesehen sind, umfassend1 . Apparatus for the detection of oxygen comprising: comprising a carrier with a plurality of wells for taking samples, wherein oxygen sensors are provided in the wells
(a) Partikel, die(a) Particles that
(i) einen lumineszierenden, durch Sauerstoff löschbaren Farbstoff und (ii) eine gasdurchlässige und im wesentlichen wasserundurchlässige erste Matrix enthalten, und(i) contain a luminescent, oxygen-erasable dye and (ii) contain a gas-permeable and substantially water-impermeable first matrix, and
(b) eine im wesentlichen wasserdurchlässige zweite Matrix, wobei die Partikel (a) in der zweiten Matrix (b) dispergiert sind.(b) a substantially water-permeable second matrix, the particles (a) being dispersed in the second matrix (b).
2. Vorrichtung nach Anspruch 1 , dadurch gekennzeichnet, dass sie als Mikrotiterplatte ausgebildet ist.2. Device according to claim 1, characterized in that it is designed as a microtiter plate.
3. Vorrichtung nach Anspruch 1 , dadurch gekennzeichnet, dass sie als Kulturplatte zur Kultivierung von Mikroorganismen oder höheren Zellen, z.B. Säugerzellen, ausgebildet ist.3. Device according to claim 1, characterized in that it is used as a culture plate for the cultivation of microorganisms or higher cells, e.g. Mammalian cells.
4. Vorrichtung nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass der lumineszierende Farbstoff ein Phosphoreszenzfarbstoff ist. 4. Device according to one of claims 1 to 3, characterized in that the luminescent dye is a phosphorescent dye.
5. Vorrichtung nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, das Farbstoff ausgewählt ist aus Pt-(ll)-porphyrinen, Pd-(ll)- porphyrinen und Ru-(ll)-Komplexen mit Poly-N-Heterocyclus, z.B. Polypyridyl-Liganden.5. Device according to one of claims 1 to 4, characterized in that the dye is selected from Pt- (ll) -porphyrins, Pd- (ll) - porphyrins and Ru- (ll) complexes with poly-N-heterocycle, e.g. -Polypyridyl ligands.
6. Vorrichtung nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass die erste Matrix Polystyrol, Polystyrolderivate oder/und Copolymere mit Polystyrol oder Polystyrolderivaten enthält.6. Device according to one of claims 1 to 5, characterized in that the first matrix contains polystyrene, polystyrene derivatives and / or copolymers with polystyrene or polystyrene derivatives.
7. Vorrichtung nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass die zweite wasserdurchlässige Matrix mindestens 10 Gew.-% Wasser aufnehmen kann.7. Device according to one of claims 1 to 6, characterized in that the second water-permeable matrix can absorb at least 10 wt .-% water.
8. Vorrichtung nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass die zweite wasserdurchlässige Matrix Polyhydroxyethylmethacrylat, quervernetztes Polγacrylamid, quervernetzten Polyvinylalkohol, hydrophile Polyurethan-Hydrogele, . quervernetztes Polyvinylpyrrolidon oder Gemische davon enthält.8. Device according to one of claims 1 to 7, characterized in that the second water-permeable matrix polyhydroxyethyl methacrylate, cross-linked polγacrylamide, cross-linked polyvinyl alcohol, hydrophilic polyurethane hydrogels,. contains cross-linked polyvinylpyrrolidone or mixtures thereof.
9. Vorrichtung nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, dass die Sauerstoff-Sensoren als Schicht mit einer Dicke von vorzugsweise 1 μm bis 100μm vorliegen.9. Device according to one of claims 1 to 8, characterized in that the oxygen sensors are present as a layer with a thickness of preferably 1 μm to 100 μm.
10. Verfahren nach einem der Ansprüche 1 bis 9, dadurch gekennzeichnet, dass die Partikel einen Durchmesser von 10 nm bis 50 μm aufweisen. 10. The method according to any one of claims 1 to 9, characterized in that the particles have a diameter of 10 nm to 50 microns.
1 1 . Vorrichtung nach einem der Ansprüche 1 bis 10, dadurch gekennzeichnet, dass mindestens zwei spektral unterschiedliche Farbstoffe vorhanden sind.1 1. Device according to one of claims 1 to 10, characterized in that at least two spectrally different dyes are present.
12. Vorrichtung nach einem der Ansprüche 1 bis 1 1 , dadurch gekennzeichnet, dass zwei spektral unterschiedliche Farbstoffe vorhanden sind, wobei der erste sauerstoffsensitiv und der zweite im Vergleich zum ersten im Wesentlichen sauerstoffinsensitiv ist.12. Device according to one of claims 1 to 1 1, characterized in that two spectrally different dyes are present, the first being oxygen-sensitive and the second being substantially oxygen-sensitive in comparison to the first.
13. Vorrichtung nach einem der Ansprüche 1 1 bis 12, dadurch gekennzeichnet, dass der zweite Farbstoff ausgewählt ist aus der Gruppe bestehend aus Rhodaminen, Xanthenoiden, Styrylfarbstoffen und13. The device according to any one of claims 1 1 to 12, characterized in that the second dye is selected from the group consisting of rhodamines, xanthenoids, styryl dyes and
Merocyaninen.Merocyanines.
14. Verwendung der Vorrichtung nach einem der Ansprüche 1 bis 1 3 um Nachweis oder/und zur Quantifizierung von Sauerstoff in einer Probe.14. Use of the device according to one of claims 1 to 1 3 for detection and / or for the quantification of oxygen in a sample.
1 5. Verwendung nach Anspruch 14 zum Nachweis oder/und zur Quantifizierung von Sauerstoff in einer biologischen Probe.1 5. Use according to claim 14 for the detection and / or for the quantification of oxygen in a biological sample.
1 6. Verwendung nach Anspruch 14 oder 1 5 zum Nachweis oder/und zur Quantifizierung von Sauerstoff in einer Kultur von Mikroorganismen oder höheren Zellen.1 6. Use according to claim 14 or 1 5 for the detection and / or for the quantification of oxygen in a culture of microorganisms or higher cells.
1 7. Verwendung nach Anspruch 14 oder 1 5 zum Nachweis oder/und zur Quantifizierung von Sauerstoff bei enzymatischen Umsetzungen. 1 7. Use according to claim 14 or 1 5 for the detection and / or for the quantification of oxygen in enzymatic reactions.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
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US29837601P | 2001-06-18 | 2001-06-18 | |
US298376P | 2001-06-18 | ||
PCT/EP2002/006662 WO2002103334A1 (en) | 2001-06-18 | 2002-06-17 | Oxygen sensors disposed on a microtiter plate |
Publications (1)
Publication Number | Publication Date |
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EP1397672A1 true EP1397672A1 (en) | 2004-03-17 |
Family
ID=23150221
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP02748791A Ceased EP1397672A1 (en) | 2001-06-18 | 2002-06-17 | Oxygen sensors disposed on a microtiter plate |
Country Status (3)
Country | Link |
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US (1) | US20040171094A1 (en) |
EP (1) | EP1397672A1 (en) |
WO (1) | WO2002103334A1 (en) |
Cited By (3)
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EP4231010A1 (en) | 2022-02-16 | 2023-08-23 | University College Cork-National University of Ireland Cork | An optochemical sensor, and uses thereof |
DE102022002116A1 (en) | 2022-06-13 | 2023-12-14 | aquila biolabs GmbH | Method and device for monitoring the contents of mixed reactors |
WO2023241869A1 (en) | 2022-06-13 | 2023-12-21 | aquila biolabs GmbH | Method and device for monitoring the contents of mixed reactors |
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WO2007075595A2 (en) * | 2005-12-20 | 2007-07-05 | Vertex Pharmacueticals Incorporated | Biofilm assay |
DE102005062003A1 (en) * | 2005-12-22 | 2007-06-28 | Endress + Hauser Conducta Gesellschaft für Mess- und Regeltechnik mbH + Co. KG | Device for detection and/or quantitative measurement of a biological substance or biological molecule, comprises a target medium, a transport medium, a receptor medium assigned to the target medium, and a measuring unit |
US7569395B2 (en) * | 2006-03-13 | 2009-08-04 | Cryovac, Inc. | Method and apparatus for measuring oxygen concentration |
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US8834795B2 (en) | 2008-12-11 | 2014-09-16 | Luxcel Biosciences Limited | Optochemical sensor for sensing O2, and method of its preparation |
US8398922B2 (en) * | 2009-10-08 | 2013-03-19 | The United States of America as represented by the Secretary of Commerce, the National Institute of Standards and Technology | Highly sensitive oxygen sensor for cell culture |
EP2625266B8 (en) * | 2010-10-04 | 2016-12-21 | Medizinische Hochschule Hannover | Process for producing three-dimensional tissue |
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ES2554077B1 (en) * | 2014-06-12 | 2016-09-20 | Juan Antonio DÍAZ MARTÍN | Polymeric chemical microsensor with fluorogenic molecular probe, manufacturing process and use for the controlled release of bioactive substances and other applications |
EP3168616A1 (en) | 2015-11-10 | 2017-05-17 | PreSens Precision Sensing GmbH | Optically active cross-linked polymer |
EP3184994B1 (en) | 2015-12-21 | 2021-11-03 | CSEM Centre Suisse d'Electronique et de Microtechnique SA - Recherche et Développement | Optical sensing film for detecting a chemical species, sensor system comprising the same and method of producing the same |
NL2019813B1 (en) | 2017-10-26 | 2018-11-06 | R&R Mechatronics Int B V | A device for assessing changes in erythrocyte deformability, such as erythrocyte sickling tendency |
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Cited By (4)
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EP4231010A1 (en) | 2022-02-16 | 2023-08-23 | University College Cork-National University of Ireland Cork | An optochemical sensor, and uses thereof |
DE102022002116A1 (en) | 2022-06-13 | 2023-12-14 | aquila biolabs GmbH | Method and device for monitoring the contents of mixed reactors |
WO2023241869A1 (en) | 2022-06-13 | 2023-12-21 | aquila biolabs GmbH | Method and device for monitoring the contents of mixed reactors |
DE102022002116B4 (en) | 2022-06-13 | 2024-01-25 | aquila biolabs GmbH | Method and device for monitoring the contents of mixed reactors |
Also Published As
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US20040171094A1 (en) | 2004-09-02 |
WO2002103334A1 (en) | 2002-12-27 |
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