WO2005095262A1 - Microcircuit integre et procede de detection de molecules et d'interactions moleculaires - Google Patents
Microcircuit integre et procede de detection de molecules et d'interactions moleculaires Download PDFInfo
- Publication number
- WO2005095262A1 WO2005095262A1 PCT/SG2005/000112 SG2005000112W WO2005095262A1 WO 2005095262 A1 WO2005095262 A1 WO 2005095262A1 SG 2005000112 W SG2005000112 W SG 2005000112W WO 2005095262 A1 WO2005095262 A1 WO 2005095262A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- test
- microchip
- channel
- fluid
- inlet
- Prior art date
Links
- 230000004001 molecular interaction Effects 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims description 53
- 238000012360 testing method Methods 0.000 claims abstract description 199
- 239000012530 fluid Substances 0.000 claims abstract description 110
- 238000001514 detection method Methods 0.000 claims abstract description 44
- 108090000790 Enzymes Proteins 0.000 claims abstract description 27
- 102000004190 Enzymes Human genes 0.000 claims abstract description 27
- 238000009792 diffusion process Methods 0.000 claims abstract description 18
- 238000004891 communication Methods 0.000 claims abstract description 14
- 239000000523 sample Substances 0.000 claims description 66
- 239000000758 substrate Substances 0.000 claims description 49
- 238000010790 dilution Methods 0.000 claims description 30
- 239000012895 dilution Substances 0.000 claims description 30
- LMDZBCPBFSXMTL-UHFFFAOYSA-N 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide Chemical compound CCN=C=NCCCN(C)C LMDZBCPBFSXMTL-UHFFFAOYSA-N 0.000 claims description 16
- WYTZZXDRDKSJID-UHFFFAOYSA-N (3-aminopropyl)triethoxysilane Chemical compound CCO[Si](OCC)(OCC)CCCN WYTZZXDRDKSJID-UHFFFAOYSA-N 0.000 claims description 14
- 239000004205 dimethyl polysiloxane Substances 0.000 claims description 11
- 239000007788 liquid Substances 0.000 claims description 11
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims description 11
- 230000003287 optical effect Effects 0.000 claims description 9
- SXRSQZLOMIGNAQ-UHFFFAOYSA-N Glutaraldehyde Chemical compound O=CCCCC=O SXRSQZLOMIGNAQ-UHFFFAOYSA-N 0.000 claims description 8
- 239000004971 Cross linker Substances 0.000 claims description 7
- 230000002401 inhibitory effect Effects 0.000 claims description 7
- -1 polydimethylsiloxane Polymers 0.000 claims description 5
- 230000003100 immobilizing effect Effects 0.000 claims description 4
- 230000005855 radiation Effects 0.000 claims description 4
- 230000002860 competitive effect Effects 0.000 claims description 3
- 230000006957 competitive inhibition Effects 0.000 claims description 3
- 239000003547 immunosorbent Substances 0.000 claims description 2
- 230000001105 regulatory effect Effects 0.000 claims 1
- 238000003018 immunoassay Methods 0.000 abstract description 9
- 238000000018 DNA microarray Methods 0.000 description 35
- 102000004169 proteins and genes Human genes 0.000 description 32
- 108090000623 proteins and genes Proteins 0.000 description 32
- 239000000243 solution Substances 0.000 description 23
- 239000000047 product Substances 0.000 description 18
- 239000000427 antigen Substances 0.000 description 13
- 108091007433 antigens Proteins 0.000 description 12
- 102000036639 antigens Human genes 0.000 description 12
- 239000012488 sample solution Substances 0.000 description 12
- 238000005406 washing Methods 0.000 description 12
- 230000003993 interaction Effects 0.000 description 10
- 238000002965 ELISA Methods 0.000 description 8
- 230000036961 partial effect Effects 0.000 description 8
- 108020004414 DNA Proteins 0.000 description 7
- 230000027455 binding Effects 0.000 description 7
- 238000006911 enzymatic reaction Methods 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000004132 cross linking Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000004033 plastic Substances 0.000 description 5
- 229920003023 plastic Polymers 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 238000013459 approach Methods 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- RINCXYDBBGOEEQ-UHFFFAOYSA-N succinic anhydride Chemical compound O=C1CCC(=O)O1 RINCXYDBBGOEEQ-UHFFFAOYSA-N 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 3
- 229920001971 elastomer Polymers 0.000 description 3
- 238000000835 electrochemical detection Methods 0.000 description 3
- 238000011534 incubation Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 102100021253 Antileukoproteinase Human genes 0.000 description 2
- 108091003079 Bovine Serum Albumin Proteins 0.000 description 2
- GAAKALASJNGQKD-UHFFFAOYSA-N LY-165163 Chemical compound C1=CC(N)=CC=C1CCN1CCN(C=2C=C(C=CC=2)C(F)(F)F)CC1 GAAKALASJNGQKD-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000003556 assay Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 2
- 229940098773 bovine serum albumin Drugs 0.000 description 2
- 239000000872 buffer Substances 0.000 description 2
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 2
- 238000007865 diluting Methods 0.000 description 2
- 238000004049 embossing Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 238000002372 labelling Methods 0.000 description 2
- 230000000670 limiting effect Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 108090000765 processed proteins & peptides Proteins 0.000 description 2
- 102000004196 processed proteins & peptides Human genes 0.000 description 2
- 239000000700 radioactive tracer Substances 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 238000002174 soft lithography Methods 0.000 description 2
- GHCZTIFQWKKGSB-UHFFFAOYSA-N 2-hydroxypropane-1,2,3-tricarboxylic acid;phosphoric acid Chemical compound OP(O)(O)=O.OC(=O)CC(O)(C(O)=O)CC(O)=O GHCZTIFQWKKGSB-UHFFFAOYSA-N 0.000 description 1
- XMWRBQBLMFGWIX-UHFFFAOYSA-N C60 fullerene Chemical compound C12=C3C(C4=C56)=C7C8=C5C5=C9C%10=C6C6=C4C1=C1C4=C6C6=C%10C%10=C9C9=C%11C5=C8C5=C8C7=C3C3=C7C2=C1C1=C2C4=C6C4=C%10C6=C9C9=C%11C5=C5C8=C3C3=C7C1=C1C2=C4C6=C2C9=C5C3=C12 XMWRBQBLMFGWIX-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 108010010803 Gelatin Proteins 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 108060003951 Immunoglobulin Proteins 0.000 description 1
- 241000283973 Oryctolagus cuniculus Species 0.000 description 1
- 238000012408 PCR amplification Methods 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000007605 air drying Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 239000012491 analyte Substances 0.000 description 1
- 230000000890 antigenic effect Effects 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 230000001588 bifunctional effect Effects 0.000 description 1
- 239000002981 blocking agent Substances 0.000 description 1
- 238000011088 calibration curve Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229920001940 conductive polymer Polymers 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000012470 diluted sample Substances 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000007876 drug discovery Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000010195 expression analysis Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 229910003472 fullerene Inorganic materials 0.000 description 1
- 229920000159 gelatin Polymers 0.000 description 1
- 239000008273 gelatin Substances 0.000 description 1
- 235000019322 gelatine Nutrition 0.000 description 1
- 235000011852 gelatine desserts Nutrition 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 102000018358 immunoglobulin Human genes 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000002493 microarray Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000009871 nonspecific binding Effects 0.000 description 1
- 244000052769 pathogen Species 0.000 description 1
- 230000001717 pathogenic effect Effects 0.000 description 1
- 239000007981 phosphate-citrate buffer Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 239000011535 reaction buffer Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000003118 sandwich ELISA Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 239000003053 toxin Substances 0.000 description 1
- 231100000765 toxin Toxicity 0.000 description 1
- 108700012359 toxins Proteins 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- 238000010200 validation analysis Methods 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 239000011534 wash buffer Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
- G01N33/543—Immunoassay; Biospecific binding assay; Materials therefor with an insoluble carrier for immobilising immunochemicals
- G01N33/54366—Apparatus specially adapted for solid-phase testing
- G01N33/54373—Apparatus specially adapted for solid-phase testing involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
- G01N33/5438—Electrodes
-
- 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
- B01L3/502746—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 the means for controlling flow resistance, e.g. flow controllers, baffles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
- G01N33/543—Immunoassay; Biospecific binding assay; Materials therefor with an insoluble carrier for immobilising immunochemicals
- G01N33/54366—Apparatus specially adapted for solid-phase testing
-
- 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
- B01L2200/02—Adapting objects or devices to another
- B01L2200/026—Fluid interfacing between devices or objects, e.g. connectors, inlet details
- B01L2200/027—Fluid interfacing between devices or objects, e.g. connectors, inlet details for microfluidic devices
-
- 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
- B01L2300/06—Auxiliary integrated devices, integrated components
- B01L2300/0627—Sensor or part of a sensor is integrated
- B01L2300/0636—Integrated biosensor, microarrays
-
- 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
- B01L2300/06—Auxiliary integrated devices, integrated components
- B01L2300/0627—Sensor or part of a sensor is integrated
- B01L2300/0645—Electrodes
-
- 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
- B01L2300/08—Geometry, shape and general structure
- B01L2300/0848—Specific forms of parts of containers
- B01L2300/0851—Bottom walls
-
- 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
- B01L2300/0861—Configuration of multiple channels and/or chambers in a single devices
- B01L2300/0864—Configuration of multiple channels and/or chambers in a single devices comprising only one inlet and multiple receiving wells, e.g. for separation, splitting
-
- 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
- B01L2300/0861—Configuration of multiple channels and/or chambers in a single devices
- B01L2300/0867—Multiple inlets and one sample wells, e.g. mixing, dilution
-
- 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
- B01L2300/0861—Configuration of multiple channels and/or chambers in a single devices
- B01L2300/0874—Three dimensional network
-
- 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
- B01L2400/0403—Moving fluids with specific forces or mechanical means specific forces
- B01L2400/0457—Moving fluids with specific forces or mechanical means specific forces passive flow or gravitation
Definitions
- the present invention relates generally to detection of molecules and molecular interactions, and more particularly to microchips and methods for detecting molecules and their interactions.
- Known detection devices of biomolecules and their interactions include microchips or biochips with arrays of addressable test sites thereon. Such devices are powerful analytical tools because hundreds or thousands of unique test sites can be analyzed simultaneously, with high throughput.
- target molecules can be captured and immobilized at different spots on the microchip for detection. Different test sites may be used to detect different target molecules or the same molecules in different samples.
- Various techniques may be used to detect the target molecules. For example, the target molecules may be detected optically or electrically.
- biomolecules or biomolecular interactions may be detected by the enzyme immunoassay (EIA) or ⁇ ed immunosorbent assay (ELISA) techniques, with extremely high and specificity.
- EIA enzyme immunoassay
- ELISA ⁇ ed immunosorbent assay
- test sites are often immersed in liquid during detection and cross-interference between different test sites can occur due to diffusion of the molecules to be detected from one test site to another. Such cross- interference can lead to false or inaccurate detection results.
- the molecules to be detected can be either the target molecules or reaction products which are to be detected to indicate the presence of the target molecules.
- a known approach to avoid cross-interference due to diffusion is to increase the distance between different test sites, to reduce the effect of diffusion.
- Ying Ding et al. disclosed a device based on the EIA electrochemical technique (EIA-EC) in "Feasibility studies of simultaneous multianalyte amperometric immunoassay based on spatial resolution", Journal of Pharmaceutical and Biomedical Analysis, (1999), vol. 19, p. 153, the contents of which are incorporated herein by reference.
- EIA-EC EIA electrochemical technique
- This spatial separation is found to be effective for avoiding cross-interference caused by diffusion when the detection measurement is completed within a certain time period after introducing the enzyme substrate.
- Such an approach also has some drawbacks.
- One problem is that only a small number of test sites can be formed on a microchip device when the distance between adjacent electrodes is so large.
- optical ELISA or EIA An alternative known approach of optical ELISA or EIA is to provide an array of isolated test wells in a chip to avoid cross-interference caused by diffusion.
- these well-based microchips have their own limitations.
- One problem is that well-density is limited, due to either manufacturing or operation requirements, so that it is difficult to form high-density test sites.
- Another problem is that a well-based microchip does not allow flow-through operation, thus making automated operation difficult. For example, automated sampling, washing, or dilution on such a chip may require expensive equipments such as robotic devices.
- test channels are in fluid communication with the inlet and outlet channels, through inlets and outlets respectively.
- Each test channel has one test site therein for detection of specific molecules or molecular interactions.
- the inlet in a test channel is elevated from the outlet of the test channel and the outlet is elevated from a fluid level in the outlet channel.
- back flow or diffusion from the outlet channel to the test channels and from the test channels to the inlet channel can be inhibited to reduce or eliminate cross-interference between different test sites.
- an aspect of the present invention relates to a microchip.
- the microchip comprises a substrate, an inlet channel in the substrate, an outlet channel in the substrate for guiding fluid below a fluid level, and a plurality of test channels in the substrate for guiding fluid flow from the inlet channel to the outlet channel.
- Each one of the test channels has an inlet for fluid communication with the inlet channel and an outlet for fluid communication with the outlet channel.
- the inlet is elevated from the outlet for inhibiting back flow through the inlet.
- the outlet is elevated from the fluid level for inhibiting back flow through the outlet.
- One test site is in each one of the test channels for detection of a specific molecule or molecular interaction at the test site.
- a microchip is provided.
- the microchip has a substrate, an inlet channel in the substrate, an outlet channel in the substrate, a plurality of test channels in the substrate each having an inlet for fluid communication with the inlet channel and an outlet for fluid communication with the outlet channel.
- the inlet is elevated from the outlet.
- One test site is in each one of the plurality of test channels. A fluid is introduced to the test channels through the inlet channel.
- Back flow through the inlets and outlets is inhibited by allowing overflow of the fluid from the test channels to the outlet channel through the outlets and maintaining the fluid level in the outlet channel below the outlets, thus inhibiting diffusion of molecules in the fluid from one of the test sites to another one of the test sites.
- a molecule or molecular interaction is detected at a test site within the plurality of test sites.
- the probe molecules may be directly immobilized on the bottom surface of the detection channel, i.e. detection well; in electronic detection, two (working and counter electrodes) or three electrodes (working, counter and reference electrodes are fabricated in the detection channels, where in all working and counter electrodes can be interconnected respectively for addressable electronic detection.
- FIG. 1 A is a plan view of a microchip, exemplary of an embodiment of the present invention.
- FIG. 1B is a cross-sectional view of the microchip of FIG. 1A taken along the line B-B;
- FIG. 2A is a plan view of another microchip exemplary of a further embodiment of the present invention.
- FIG. 2B is a partial cross-sectional view of the microchip of FIG. 2A taken along the line B-B;
- FIG. 3A is a partial cross-sectional view of a variation of the microchip of FIG. 2A and 2B; [0021] FIG. 3B is a partial plan view of the microchip of FIG. 3A;
- FIG. 4 is a partial plan view of a variation of the microchip of FIG. 3A;
- FIGS. 5A and 5B are schematic diagrams illustrating exemplary enzyme immunoassay techniques
- FIG. 6A is a partial image of a mold for forming a microchip.
- FIG. 6B is a partial image of a microchip formed from the mold of FIG. 6A.
- FIGS. 1A and 1B illustrate a microchip or microfluidic biochip 100, exemplary of an embodiment of the present invention.
- Biochip 100 includes a substrate 102.
- An inlet channel 104, an outlet channel 106, and a plurality of test channels 108 are formed in substrate 102.
- the test channels 108 may be substantially parallel to each other.
- Inlet channel 104 is in fluid communication with, and can receive fluid from, a dilution channel 110.
- Dilution channel 110 has multiple inlets 112A to 112D (also collectively and individually referred to as 112), each for introducing or feeding a fluid into dilution channel 110.
- Each test channel 108 has an inlet 114 and an outlet 116.
- Each test channel 108 is in fluid communication with inlet channel 104 through inlet 114 and with outlet channel 106 through outlet 116. While four test channels 108 are depicted in FIG. 1A, the number of test channels 108 may vary depending on the particular application and manufacturing considerations.
- Each test channel 108 has one test site therein for detection of a specific molecule or molecular interaction at the test site, as will be
- a test channel 108 has a bottom 118 and an overflow wall 120 which forms the lower end of outlet 116.
- wall 120 is optional and can be omitted.
- a test well is formed in each channel 108. The well structure may be advantageous in some applications, as will become clear below.
- outlet channel 106 has a bottom
- inlet 14 is elevated from outlet 116, which is in turn elevated from the fluid level 124 in outlet channel 106.
- inlet channel 104 can thus guide fluid at a fluid level above the fluid level in each test channel 108.
- a test channel 108 can hold fluid at a fluid level up to outlet 116, as indicated by the dashed line 126 in FIG. 1B, which is at a level above the fluid level 124 in outlet channel 106.
- back flow or diffusion through inlet 114 or outlet 116 can therefore be inhibited, thus limiting or eliminating cross-interference due to diffusion of molecules in the fluid from one test site to another test site.
- a sample fluid may be diluted in dilution channel 110.
- Inlets 112 can be conveniently used to dilute the sample fluid multiple times. The number of inlets 112 may vary, for example, depending on the sample concentration and the desired amount of dilution.
- One of the inlets 112, such as inlet 112A may be adapted for connection to a sample source (not shown) and the other inlets such as 112B to 112D may be adapted for connection to a dilution solution source (not shown).
- Inlets 112 may also be connected to one or both of a substrate solution source and a washing solution source (not shown).
- Outlet channel 106 may be connected to a waste dispenser (not shown).
- Substrate 102 can be made of a suitable material such as plastic, ceramic, graphite, glass, rubber, fabric, printed circuit board, silicon, suitable polymer, or the like. A combination of two or more of these materials may also be used. Substrate 102 can be prepared in a suitable manner known to persons skilled in the art.
- Channels 104, 106, 108, and 110 can each has a width or depth on the order of 0.02 ⁇ m to 2000 ⁇ m, depending on the application. They can have different widths and depths.
- inlet channel 104 can have a width of about 200 ⁇ m and a depth of about 50 ⁇ m
- outlet channel 106 can have a width of about 300 ⁇ m and a depth of about 200 ⁇ m
- each test channel 108 can have a width of about 100 ⁇ m and a well depth of about 150 ⁇ m, wherein all depths are relative to the top surface of substrate 102.
- the liquid flow rate is faster in outlet channel 106 than in inlet channel 104, which can be advantageous because it reduces the chance for fluid to overflow from test channels 108 back into inlet channel 104.
- Channels 110 is shaped and sized for supplying a fluid to inlet channel 104 at a desired rate and for effectively diluting the fluid by a desired ratio.
- the size of channel 110 can be readily determined by a person skilled in the art for a given application.
- Channels 104, 106, 108 and 110 may be formed using conventional microchip fabrication techniques including etching, embossing, molding, or the like.
- a silicon mold can be fabricated using a soft-lithography method to make a master device and then a rubbery polymer (such as polydimethylsiloxane (PDMS)) substrate can be formed from the mold.
- PDMS polydimethylsiloxane
- Channel surfaces may be coated with a polymeric, metallic, or ceramic material, or other materials if desired.
- the test site of each test channel 108 may have a surface, such as bottom surface 118, suitable for immobilizing molecules thereon.
- the surface can be made of a plastic such as polyvinyl, polystyrene, or cellulose.
- Probe molecules (not shown) may be immobilized at the test site in each test channel 108. Probe molecules may be immobilized using a conventional immobilization technique, including physical adsorption, cross-linking, entrapment, covalent bonding, grafting, or a combination of the foregoing techniques.
- Probe molecules can be immobilized with a robotic nano- or pico- dispenser, or by introducing a fluid containing the probe molecules to test channels 108.
- the test channel surface may be coated with a surface that is suitable for selectively immobilizing probe molecules.
- the surface may be coated with aminopropyltriethoxysilane (APTES).
- APTES aminopropyltriethoxysilane
- the coated surface may then be treated with a suitable cross-linker for capturing the probe molecules.
- homo- bifunctional cross-linkers such as glutaraldehyde, or heterobifunctional cross-linkers such as 1-ethyl-3-(3-dimethylaminopropyl)carbodi-imide (EDC) may be applied to the APTES surface for selectively binding probe proteins.
- Immobilization of probe molecules can be optionally performed during use before detection. After probe immobilization, a thorough wash of the channels including the test channels can be conducted. The channel surfaces outside the test sites can be coated with blocking agents such as gelatin to eliminate non-specific binding of molecules to these surfaces. The washing and blocking can be conducted by automatic operation by connecting biochip 100 to a pumping system.
- a cover (not shown), such as a transparent cover plate, may be provided on the top of substrate 102 to seal the channels and the test channels for flow-through operation.
- the cover can be made of a glass, plastic, or acrylic sheet.
- a film with one adhesive side may be used as the cover.
- the cover can prevent contamination during use.
- a transparent cover may allow detection of optical signals originated from the test channels 108.
- fluid sources such as sample sources, substrate sources, washing fluid sources may be provided or linked to dilution channel 110, such as through one or more of inlets 112. In an alternative embodiment, some fluid sources may be connected directly to inlet channel 104, bypassing dilution channel 110.
- Fluid pumps (not shown) and valves (not shown) for controlling fluid flow in the channels and for supplying fluid to, or withdrawing fluid from, the channels may be provided.
- Electrical interconnects (not shown) and circuitry may be provided for controlling the operation of biochip 100 and/or for measuring or detecting a signal such as an optical or electrical signal from the test sites in test channels 108.
- a fluid such as a sample fluid containing target molecules or a washing buffer solution, is introduced into test channels 108 through inlet channel 106 and inlets 116.
- the sample fluid may be fed into dilution channel 110 through one of inlets 112, such as inlet 112A.
- Dilution fluids may be fed into dilution channel 110 through other inlets 112, such as inlets 112B to 112D, to dilute the sample fluid.
- the sample fluid can be diluted multiple times by introducing a dilution fluid at each one of a number of inlets 112.
- the dilution ratio at each inlet 112 can be individually controlled by adjusting the flow rates at inlets 112.
- the diluted sample fluid is received in inlet channel 104 and then in test channels 108. However, when dilution is not required or desired, a sample solution may be introduced into test channels 108 through inlet channel 104 without dilution.
- Different fluids may be introduced into each test channel 108 depending on the detection technique used.
- the fluids introduced may include probe solutions, sample solutions, washing solutions, substrate solutions, solutions containing labelling or signal generating molecules, and the like, as will be understood by persons skilled in the art.
- a continuous fluid flow may be maintained.
- fluid flow may be stopped for a certain period of time to allow certain interactions to occur, such as for incubation.
- a molecule or molecular interaction is then detected at one, some or each of the test sites.
- the molecule detected can be a target molecule, or a signal generating molecule for indirect detection of the target molecule.
- the molecule or molecular interaction can be detected using various techniques, including conventional detection techniques for detecting molecules and molecular interactions.
- the molecule or molecular interaction may be detected by detecting an optical, electrical, magnetic, radiation or electromagnetic signal indicative of the presence of the target molecule or occurrence of the molecular interaction.
- Example detection techniques include enzyme immunoassay (EIA) techniques.
- An EIA technique can be performed with an electrochemical detection technique (electrochemical EIA or EIA-EC) or with an optical detection technique.
- EIA techniques include enzyme-linked immunosorbent assay (ELISA), direct EIA, competitive EIA, competitive inhibition EIA, sandwich EIA, and the like.
- ELISA enzyme-linked immunosorbent assay
- the signal generating molecules can be product molecules produced from enzyme-catalysed reactions, which may be mobile in a fluid.
- the enzyme-catalyzed interaction or its product can be detected.
- the interaction may generate heat, light, radiation, or sound.
- the reaction product may be electrochemically active or fluorescent. Detection of the enzyme- catalyzed interaction or its product can thus indicate the presence of the target molecules.
- detection of fluorescent light from a test channel can indicate the presence of the target molecules in the sample solution. It can then be determined that the target molecules are present in the sample solution.
- the intensity of the fluorescent light can also indicate the concentration of the target molecules in the sample solution. Since back flow or diffusion is inhibited, cross-interference due to diffusion of these product molecules can be avoided or reduced.
- the target molecule may be captured by probe molecules immobilized at the test site. Probe molecules may be pre-immobilized or immobilized during use. Different probe molecules may be immobilized at different test sites for detecting different target molecules.
- probe proteins can be pre-immobilized on the bottom
- test site 118 of a test channel 108, thus defining the test site.
- target protein allows for enzyme labelling, a direct EIA or
- the probe proteins can selectively capture target molecules, which are labelled with enzymes, in a sample fluid introduced into the test channels.
- a substrate fluid can be then introduced into the test channel.
- the substrates in the substrate fluid can produce detectable products in reactions catalysed by the enzymes attached to the target molecules at a test site. The higher the concentration of target molecules in the sample fluid, the more target molecules will be captured and thus producing a stronger signal.
- the probe molecules can selectively capture a specific protein in a complex, which can contain either a target protein or an enzyme-conjugated competing protein.
- a sample fluid containing unknown concentrations of target molecules can be first introduced into a test channel 108. The target molecules are captured at some of the binding sites.
- a fluid containing known concentrations of competing proteins is then introduced into test channel 108. The competing proteins are captured at the remaining binding sites. By detecting how many competing proteins are captured, the presence or concentration of the target proteins can be indirectly detected.
- the probe molecules immobilized on the bottom surface of a test channel 108 can be the same type of molecules as the target molecules, such as the same antigens.
- a sample fluid and a fluid containing enzyme-labelled molecules such as antibodies of a known concentration can be introduced into the test channel.
- An enzyme-labelled molecule can bind to either a target molecule or a probe molecule.
- Enzyme-labelled molecules attached to the target molecules cannot interact with the probe molecules.
- the presence of target molecules at the test site can inhibit a signal that would have resulted from interactions between enzyme-labelled molecules and probe molecules.
- the intensity of a detected signal can be inversely proportional to the concentration of the target molecules in the test channel.
- This technique can be particularly useful for detection of small proteins without a second epitope for enzyme labels.
- the target protein may be captured by the probe protein.
- the test channels may be washed after introducing the sample fluid.
- a fluid containing some other proteins labelled with enzymes may be introduced into the test channel to allow the other proteins to bind to the target proteins.
- the test channels may be washed before conducting the ELISA detection.
- a capture target protein is sandwiched between two proteins, the probe protein and the enzyme-labelled protein.
- the captured molecules or proteins including target molecules can be detected, for example, after introducing a fluid containing substrate molecules that can be converted by enzymatic reactions to coloured products for optical detection or electrochemically active products for the electrochemical detection.
- test channels As mentioned above, after a fluid is introduced into test channels
- the channels may be washed with a washing fluid, which may be fed into inlet channel 104 through dilution channel 110.
- samples containing same or different types of target molecules may be transported into different test channels 108 for simultaneous detection of multi-analytes when the different test channels 108 have different probe molecules immobilized therein.
- the target molecules may be detected without an enzyme attached thereto.
- the target molecules may be labeled with radioactive tracers and detected by sensing a radiation from each test channel 108.
- the target molecules may be detected without a label. For example, certain interaction of a specific molecule with another molecule may produce detectable heat or light.
- back diffusion can be inhibited or limited, and multiple sample tests can be simultaneously performed on biochip 100.
- biochip 100 can be conveniently used for analysis of both low and high concentration samples.
- the sample fluid can be conveniently diluted on biochip 100. Saturation in the test channels can be avoided even when the sample initially has very high concentrations of target molecules. Dilution can be carried out in multiple steps thus reducing the concentration at each step. As can be understood, when the dilution ratio is very high in a single dilution step, large errors can result. Thus, diluting at a low dilution ratio at each step can reduce the errors than may result from dilution. Dilution on biochip 100 can be carried out automatically.
- FIGS. 2A and 2B illustrate a microfluidic biochip 200, exemplary of another embodiment of the present invention, which has an X-Y addressable array of test sites.
- Microchip or biochip 200 has a substrate 202 and inlet, outlet and test channels 204, 206, and 208 formed therein.
- Test channels 208 are arranged in rows and columns. Multiple columns of test channels 208 are formed in substrate 202. The number of test channels 208 may vary and can be selected depending on the particular application and manufacturing considerations.
- Each column of test channels 208 are separated into multiple rows by sidewalls 210 and share a common inlet channel 204 and a common outlet channel 206. Rows of test channels 208 in different columns are aligned for convenient addressing.
- each test channel 208 which comprises a pair of electrodes 212, one of which is a working electrode and the other a counter or counter/reference electrode.
- counter electrodes may be replaced by reference electrodes.
- a reference electrode may be added in each test channel 208.
- electrodes 212 are formed on the opposite sidewalls 210 within each test channel 208.
- each channel 204, 206 and 208 has a substantially flat bottom 214, 216 or 218.
- Bottom 214 is elevated from bottom 218, which is in turn elevated from bottom 216. Therefore, as with microchip 100, back diffusion from one test site to anther test site can be inhibited in microchip 200.
- the respective amount of elevation can be readily determined by persons skilled in the art depending on the application. For example, each elevation may vary between 25 and 100 ⁇ m.
- the channels may also be structured similar to that of microchip 100. In particular, a well may be formed in each test channels.
- the detection of molecules or molecular interactions at each test site can be conducted using electrodes 212.
- the working electrodes 212 in each row and column can be respectively interconnected.
- the counter electrodes 212 in each row and column can be respectively interconnected.
- Each row of electrodes can have an X address, such as X1 to X4, and each column of electrodes can have a Y address, such as Y1 to Y4.
- the electrodes in each test channel can be addressed with an X-Y addressing technique.
- Conventional X-Y addressing techniques such as multiplexing techniques can be used. Such a technique can be readily implemented by a person skilled in the art.
- electrical interconnections or I/O lines can be limited with simple multiplexing, as can be understood by a person of skill in the art.
- the substrate and channels of microchip 200 may be formed as described above for microchip 100.
- Electrodes 212 may be formed using any suitable technique including conventional techniques for forming electrodes. Electrodes 212 may have any suitable shape or size. Different electrodes may have different shapes and sizes or made of different materials. Working electrodes in different test channels may be spaced apart at distances on the order of 0.01 ⁇ m to 1000 ⁇ m, depending on the application and manufacturing limitations. Electrodes 212 may be made of a solid or porous material such as gold, silver, platinum, copper, titanium, chromium, aluminum, metal oxide, metal carbide, carbon, graphite, fullerene, conductive plastic, conductive polymer, metal impregnated polymers, or the like. A combination of two or more of these materials can be used.
- Probe molecules may be immobilized on working electrodes 212 or on bottoms 218 of test channels 208 proximate electrodes 212-
- a cover (not shown), such as a transparent cover plate, may be optionally provided on the top of the substrate to cover the channels for sealing the flow-through channels.
- Biochip 200 may be operated in a similar manner as for biochip 100.
- fluid sources such as sample sources, substrate sources, washing solution sources may be provided or linked to input channel 204.
- Fluid pumps (not shown) and valves (not shown) for controlling fluid flow in the channels and for supplying fluids to the channels may be provided.
- Electrical interconnects (not shown) and circuitry (not shown) may be provided for biasing electrodes 212 and for measuring electrical signals such as voltages and currents at electrodes 212.
- Biochip 200 may be operated in a similar manner as for biochip 100.
- an electrical signal can be sensed using electrodes 212 for detecting molecules or molecular interactions at each test site.
- the reaction products of the molecular interactions may comprise electrochemically active molecules.
- Each pair of electrodes 212 in a test channel 208 is biased to monitor the electrochemical reactivity at the test site in the test channel.
- an electrical current can flow between the pair of electrodes 212.
- a highly concentrated substrate solution can be used to produce a high concentration of electrochemically active products even when the target molecules have a very low concentration in the sample solution.
- a technique can be highly sensitive.
- the product concentration can be significantly increased for high sensitivity detection by increasing the incubation time for the enzymatic reaction.
- the amount of electrochemically active products produced at a test site can be detected by monitoring an electrical signal at electrodes 212, such as a current through an electrode 212.
- the concentration of the target molecules can be determined, for example, by comparing the detected current with a calibration curve of current vs. concentration, which can be obtained by measuring samples with known concentration of target molecules.
- the current due to generation of the electrochemically active products produced from the enzymatic reaction can be proportional to the concentration of the product, and can be approximately proportional to the target concentration in the sample solution.
- test sites are separated by the sidewalls
- each test channel 208 proximate the test site i.e. electrodes 212
- FIGS. 3A and 3B illustrate a biochip 300 which is a variation of biochip 200.
- biochip 300 includes a substrate 302, and an inlet channel 304, an outlet channel 306, and a plurality of test channels 308 formed therein.
- Inlet channel 304 has a bottom surface 314.
- Outlet channel 306 has a bottom surface 316.
- Test channels 308 are defined by sidewalls 310 and bottom surface 318.
- Biochip 300 has a panel 320 extending between sidewalls 310 and elevated from bottom surface 318, thus defining an opening 322 to allow the liquid to flow through.
- the narrowed section at opening 322 guides fluid towards the test site for effective contact with electrodes 212 or a surface having probe molecules immobilized thereon.
- Panel 320 can also further prevent backflow.
- Panel 320 may be shifted vertically to van/ opening 322 for controlling the flow rate.
- Electrodes 212 may be disposed in a test channel differently than as shown in FIGS. 3A and 3B.
- electrodes such as electrodes 412
- a pair of working and counter/reference electrodes 412 may be disposed at bottom 318 adjacent opposite sidewalls, as depicted.
- probe molecules can be immobilized on a surface in a test channel.
- Probe molecules may include antibodies, antigens, peptides, aptomers, DNAs, and the like, which can specifically capture and bind to the target molecules.
- Probe molecules can capture target molecules contained in a sample solution introduced into the test channels. The sample solution may be flown through each test channel to allow the target molecules and/or enzyme-labelled molecules (reporter molecules) to be captured by the probe molecules.
- the reporter molecules in a competition detection scheme are labelled with enzyme molecules.
- a reporter molecule can be an antibody, antigen or any molecule with affinity to the probe molecule.
- the target molecules may be directly labelled before they react with the probe molecules.
- a liquid may be flown through the channels to attach a next molecule to the already immobilized molecule.
- the channels may be washed with a washing solution before feeding the next liquid.
- the channels may be washed before providing substrate solutions to the test channels to ensure that mobile enzymes are removed from the test channels.
- FIG. 5A A specific example of a sandwich immunoassay technique is illustrated in FIG. 5A.
- a probe antibody is immobilized on the surface of a working electrode or surface close to the working electrode.
- the target molecule is an antigen of interest and is bond to the probe antibody.
- An enzyme (such as ALP)-labelled second antibody is transported to bind to the target antigen after washing.
- the substrate such as a PAPP including dephosphorylase-PAPP, is delivered into the detection spots for an enzymatic reaction, for example by flowing a substrate solution through the test channels.
- the substrate molecule reacts under enzyme catalysis at the enzyme active site to produce an electrochemically active product, PAP.
- PAP can be detected electrochemically when the electrodes are biased to a low potential such as 300 mv with reference to an Ag/Ag reference electrode.
- a probe DNA is first immobilized on the electrode surface.
- the target DNA is then bond to the probe DNA.
- the target DNA is labelled with an ALP enzyme.
- the enzyme can catalyse conversion of PAPP substrates to PAP products as in FIG. 5A for electrochemical detection.
- FIG. 6A shows a partial image of a silicon mold for forming a biochip exemplary of embodiments of the present invention.
- the mold was prepared with a soft-lithography method.
- the test channels (seen as parallel narrow channels) have widths of about 100 ⁇ m.
- FIG. 6B shows a partial image of a biochip formed from the mold shown in FIG. 6A.
- the biochip was formed by pouring a rubbery polymer (PDMS) over the mold, curing the polymer, and then separating the cured polymer from the mold.
- the biochip is suitable for ELISA analysis or detection. Probe antigens were immobilized in the test channels.
- a transparent polyacrylic sheet was attached to the biochip as the cover for sealing the device.
- target proteins were immobilized as follows on the biochips.
- a thin aminopropyltriethoxysilane (APTES) film was coated or grafted on the PDMS surface of the test channels.
- the APTES surface was treated with homo-bifunctional cross-linkers (glutaraldehyde) for capturing immunoglobulin proteins on the APTES film.
- succinic acid anhydride generated carboxyl groups were applied onto the APTES surface, and heterobifunctional cross-linkers (1-ethyl-3-(3-dimethylaminopropyl)carbodi- imide (EDC)) were then applied to the surface to covalently bind proteins onto the PDMS-APTES surface through the carboxyl groups.
- EDC 1-ethyl-3-(3-dimethylaminopropyl)carbodi- imide
- a PDMS-APTES surface can be prepared by first cleaning the
- PDMS surface and then immersing the surface in an ethanol solution containing about 10% v/v APTES for about 10 minutes at room temperature.
- the APTES treated PDMS is rinsed with 96% ethanol, followed by air-drying, and then heated at 80 °C in a vacuum oven for about 2 hours.
- Covalent immobilization can be realized via EDC as follows.
- Succinic acid anhydride can be first used to modify the APTES surface by immersing the PDMS-APTES surface in a 50g/ml SAA solution for about 2 hours at room temperature.
- the pH value of the solution is adjusted by using a 3M NaOH solution to keep the solution stable at pH 6.0.
- surface is rinsed by phosphate- citrate buffer and dried under nitrogen flow.
- EDC and protein mixture are dropped onto the modified solid surface for cross-linking.
- the concentration of the EDC is 20 ⁇ g/ml.
- the reaction buffer has 0.01 M of phosphate-citrate, with a pH of 4.6.
- the cross-linking process lasts for about 1 hour at room temperature.
- the cross-linking process is terminated by immersing the surface in a Tris-HCI buffer.
- the protein coated surface is then immersed in a 1 % bovine serum albumin (BSA) for blocking unoccupied surface for about 2 hours at about 37°C or for about 8 hours at room temperature.
- BSA bovine serum albumin
- Covalent immobilization can also be realized via glutaraldehyde (GA) as follows.
- the APTES treated PDMS surface is modified by GA to covalently immobilize protein on the PDMS surface.
- the amino groups on the surface are activated by 2.5% GA for 1 hour at room temperature.
- the surface is rinsed with a pH 8.0 Tris-HCI buffer, and dried with nitrogen gas. Protein probes in Tris-HCI are added onto the glutaraldehyde-activated surface.
- the cross-linking reaction can take place at room temperature for about 2 hour. After washing, the protein-coated surface is surface-blocked with the block reagent described above.
- Example biochips fabricated as above have shown good performance.
- rabbit IgG were immobilized in the test channels as described in the preceding paragraph.
- Sample solutions containing varying concentrations of enzymes labeled with anti-rabbit IgG were flown through the channels and test channels to immobilize the enzymes in the test channels by antibody-antigen binding.
- the channels and test channels was washed with a washing solution.
- a substrate solution was then flown through the test channels. Fluorescent light emitted from the test channels was detected.
- the intensities of the fluorescent light were substantially linearly dependent on the concentration of the sample solutions. The linear dependence indicates that cross-interference between test channels was very low. It has been found that as low as about 5.6 pg/ml of enzyme concentration can be detected.
- Exemplary embodiments disclosed herein are useful for detecting low level of antigens, antibodies, peptides, DNA, proteins and other biomolecules in fluid or tissue samples.
- Low levels of DNA, RNA and other biomolecules such as glucose, which can be enzymatically converted to electrochemically active species, can be detected using embodiments of the present invention.
- Embodiments of the present invention can be incorporated into existing optical detection systems based on enzyme-catalyzed bio-reactions, in which PCR amplification can be eliminated.
- the exemplary biochips disclosed herein may provide a basic platform for a variety of applications, for example in diagnostics, drug discovery, target validation and pathogen detection.
- Embodiments of the invention can be used in competition and displacement immunoassays where target antigens are labeled with enzymes for competition binding or displacement for detection. Radioactive tracers can be used to label the target molecules or binding molecules as reporters.
- the sandwich immunoassay is suitable for use with high molecular weight antigens, which possess at least two antigenic determinants or epitopes, but the competition and displacement immunoassay can be used to detect different antigens.
- biochips described herein can be automated.
- the biochips can be connected to utility modules.
- the operation of a biochip can be controlled by a computer or a microprocessor.
- the liquid flow rate and flow time can be conveniently adjusted.
- the substrate solution can continuously flow through the test sites generating more and more product molecules, even a low concentration of target molecules in the analyte. solution can be detected.
- the substrate solution can also have a high concentration of substrate molecules.
- the liquid flow rate and flow time can be conveniently adjusted to control the enzyme reaction, for example, for achieving different detection sensitivities.
- target molecules can be immobilized or labelled in other suitable manners.
- the surface of an electrode may have a coating that can selectively capture the target molecules.
- the target molecule when the target molecule is itself an enzyme, it may not be necessary to attach another enzyme to it.
- the enzyme reactions or target molecules present at different test sites can be identified using electrode addressing techniques including conventional addressing techniques.
- the test sites may form an array of rows and columns and X-Y addressing techniques may be used.
- high-density array biochips disclosed herein can be made compact without creating substantial cross-interference for a flow-through system. It can also be fabricated inexpensively and easily, for example, using inexpensive and matured printed circuit board technology to fabricate a plastic based microarray chip with microchannels, or embossing fabrication process. [0088] As can be appreciated, working and counter or reference electrodes
- each test channel 208 may be interchangeable.
- separate counter and reference electrodes thus more than two electrodes, can be provided in each test channel 208.
- the reference electrodes can be interconnected with each other. The implementation and operation of electrodes for detecting electrochemical reactions including the use of reference electrodes can be readily understood by persons skilled in the art.
- Embodiments of the invention may also be useful in protein expression profiling. Measurement of the variation in the expression of known proteins within tissues or cells over time, or in response to challenge by drugs, toxins, injury or disease, may require high throughput operation and can be conveniently performed using embodiments of the present invention.
- Embodiments of the invention can be used in high density array- sensors with high sensitivity and specificity. Accuracy and reliability of the embodiments disclosed herein can be high because cross-interference due to diffusion can be inhibited or limited. It is also convenient to perform multi-fold dilution of sample, automatic post-immobilization probe treatment, and washing.
- array dispensers are not necessary for operating biochips disclosed herein.
- Total assay time can be reduced compared to conventional biochips.
- the requirement of the samples amount is significantly decreased.
Landscapes
- Health & Medical Sciences (AREA)
- Immunology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Hematology (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Urology & Nephrology (AREA)
- General Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Food Science & Technology (AREA)
- Microbiology (AREA)
- Medicinal Chemistry (AREA)
- Physics & Mathematics (AREA)
- Cell Biology (AREA)
- Biochemistry (AREA)
- Biotechnology (AREA)
- General Physics & Mathematics (AREA)
- Pathology (AREA)
- Dispersion Chemistry (AREA)
- Clinical Laboratory Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Apparatus Associated With Microorganisms And Enzymes (AREA)
Abstract
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/547,405 US9863941B2 (en) | 2004-04-01 | 2005-04-01 | Microchip and method for detecting molecules and molecular interactions |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US55811804P | 2004-04-01 | 2004-04-01 | |
US55811604P | 2004-04-01 | 2004-04-01 | |
US60/558,118 | 2004-04-01 | ||
US60/558,116 | 2004-04-01 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005095262A1 true WO2005095262A1 (fr) | 2005-10-13 |
Family
ID=35063656
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/SG2005/000112 WO2005095262A1 (fr) | 2004-04-01 | 2005-04-01 | Microcircuit integre et procede de detection de molecules et d'interactions moleculaires |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO2005095262A1 (fr) |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2009153763A1 (fr) * | 2008-06-20 | 2009-12-23 | International Business Machines Corporation | Sélection microfluidique d'éléments de bibliothèque |
US8383025B2 (en) | 2009-05-19 | 2013-02-26 | Nanyang Technological University | Method of manufacturing micro patterned device and device obtained by the method |
US9180449B2 (en) | 2012-06-12 | 2015-11-10 | Hach Company | Mobile water analysis |
US9182353B2 (en) | 2010-07-22 | 2015-11-10 | Hach Company | Lab-on-a-chip for alkalinity analysis |
USD768872S1 (en) | 2012-12-12 | 2016-10-11 | Hach Company | Cuvette for a water analysis instrument |
US9879360B2 (en) | 2008-06-20 | 2018-01-30 | International Business Machines Corporation | Microfluidic selection of library elements |
CN112198329A (zh) * | 2011-01-28 | 2021-01-08 | 匡特里克斯公司 | 用于分子或粒子的超灵敏探测的系统、装置以及方法 |
US10989713B2 (en) | 2010-03-01 | 2021-04-27 | Quanterix Corporation | Methods and systems for extending dynamic range in assays for the detection of molecules or particles |
US11237171B2 (en) | 2006-02-21 | 2022-02-01 | Trustees Of Tufts College | Methods and arrays for target analyte detection and determination of target analyte concentration in solution |
US11275092B2 (en) | 2011-04-12 | 2022-03-15 | Quanterix Corporation | Methods of determining a treatment protocol for and/or a prognosis of a patient's recovery from a brain injury |
US11434264B2 (en) | 2015-02-13 | 2022-09-06 | Quanterix Corporation | Immunoassays for differential detection of clostridium difficile |
US11619631B2 (en) | 2010-03-01 | 2023-04-04 | Quanterix Corporation | Ultra-sensitive detection of molecules or particles using beads or other capture objects |
CN116203226A (zh) * | 2021-11-30 | 2023-06-02 | 苏州科技大学 | 自动化电化学微流控酶联免疫法检测生物芯片及其应用 |
CN116203228A (zh) * | 2021-11-30 | 2023-06-02 | 苏州科技大学 | 基于dna信号放大和电化学检测的超灵敏微流控三明治酶联免疫法检测平台和应用 |
WO2024011134A1 (fr) * | 2022-07-05 | 2024-01-11 | IsoPlexis Corporation | Systèmes, dispositifs et procédés d'analyse multiplexée |
US11874279B2 (en) | 2006-02-21 | 2024-01-16 | Trustees Of Tufts College | Methods and arrays for target analyte detection and determination of target analyte concentration in solution |
EP4480581A1 (fr) * | 2023-06-23 | 2024-12-25 | Koninklijke Philips N.V. | Dispositif fluidique et son utilisation |
WO2024261021A1 (fr) | 2023-06-23 | 2024-12-26 | Koninklijke Philips N.V. | Dispositif fluidique et son utilisation |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002068823A1 (fr) * | 2000-11-06 | 2002-09-06 | Nanostream Inc. | Composants microfluidiques a ecoulement unidirectionnel |
US20020185183A1 (en) * | 2001-06-07 | 2002-12-12 | Nanostream, Inc. | Microfluidic devices with distributing inputs |
WO2003035229A2 (fr) * | 2001-10-26 | 2003-05-01 | Ntu Ventures Pte Ltd | Puce integree de preparation d'echantillons |
WO2003052428A1 (fr) * | 2001-02-07 | 2003-06-26 | Biomicro Systems, Inc. | Dispositif microfluidique tridimensionnel comprenant des structures de regulation passive des fluides |
EP1357178A1 (fr) * | 2002-04-22 | 2003-10-29 | ibidi GmbH | Sytème microfluide |
-
2005
- 2005-04-01 WO PCT/SG2005/000112 patent/WO2005095262A1/fr active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002068823A1 (fr) * | 2000-11-06 | 2002-09-06 | Nanostream Inc. | Composants microfluidiques a ecoulement unidirectionnel |
WO2003052428A1 (fr) * | 2001-02-07 | 2003-06-26 | Biomicro Systems, Inc. | Dispositif microfluidique tridimensionnel comprenant des structures de regulation passive des fluides |
US20020185183A1 (en) * | 2001-06-07 | 2002-12-12 | Nanostream, Inc. | Microfluidic devices with distributing inputs |
WO2003035229A2 (fr) * | 2001-10-26 | 2003-05-01 | Ntu Ventures Pte Ltd | Puce integree de preparation d'echantillons |
EP1357178A1 (fr) * | 2002-04-22 | 2003-10-29 | ibidi GmbH | Sytème microfluide |
Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11237171B2 (en) | 2006-02-21 | 2022-02-01 | Trustees Of Tufts College | Methods and arrays for target analyte detection and determination of target analyte concentration in solution |
US11874279B2 (en) | 2006-02-21 | 2024-01-16 | Trustees Of Tufts College | Methods and arrays for target analyte detection and determination of target analyte concentration in solution |
US9879360B2 (en) | 2008-06-20 | 2018-01-30 | International Business Machines Corporation | Microfluidic selection of library elements |
WO2009153763A1 (fr) * | 2008-06-20 | 2009-12-23 | International Business Machines Corporation | Sélection microfluidique d'éléments de bibliothèque |
US8383025B2 (en) | 2009-05-19 | 2013-02-26 | Nanyang Technological University | Method of manufacturing micro patterned device and device obtained by the method |
US11619631B2 (en) | 2010-03-01 | 2023-04-04 | Quanterix Corporation | Ultra-sensitive detection of molecules or particles using beads or other capture objects |
US12019072B2 (en) | 2010-03-01 | 2024-06-25 | Quanterix Corporation | Methods and systems for extending dynamic range in assays for the detection of molecules or particles |
US10989713B2 (en) | 2010-03-01 | 2021-04-27 | Quanterix Corporation | Methods and systems for extending dynamic range in assays for the detection of molecules or particles |
US9182353B2 (en) | 2010-07-22 | 2015-11-10 | Hach Company | Lab-on-a-chip for alkalinity analysis |
US11977087B2 (en) | 2011-01-28 | 2024-05-07 | Quanterix Corporation | Systems, devices, and methods for ultra-sensitive detection of molecules or particles |
CN112198329A (zh) * | 2011-01-28 | 2021-01-08 | 匡特里克斯公司 | 用于分子或粒子的超灵敏探测的系统、装置以及方法 |
US11112415B2 (en) | 2011-01-28 | 2021-09-07 | Quanterix Corporation | Systems, devices, and methods for ultra-sensitive detection of molecules or particles |
US11275092B2 (en) | 2011-04-12 | 2022-03-15 | Quanterix Corporation | Methods of determining a treatment protocol for and/or a prognosis of a patient's recovery from a brain injury |
US9180449B2 (en) | 2012-06-12 | 2015-11-10 | Hach Company | Mobile water analysis |
USD768872S1 (en) | 2012-12-12 | 2016-10-11 | Hach Company | Cuvette for a water analysis instrument |
US11434264B2 (en) | 2015-02-13 | 2022-09-06 | Quanterix Corporation | Immunoassays for differential detection of clostridium difficile |
CN116203226A (zh) * | 2021-11-30 | 2023-06-02 | 苏州科技大学 | 自动化电化学微流控酶联免疫法检测生物芯片及其应用 |
CN116203228A (zh) * | 2021-11-30 | 2023-06-02 | 苏州科技大学 | 基于dna信号放大和电化学检测的超灵敏微流控三明治酶联免疫法检测平台和应用 |
WO2024011134A1 (fr) * | 2022-07-05 | 2024-01-11 | IsoPlexis Corporation | Systèmes, dispositifs et procédés d'analyse multiplexée |
EP4480581A1 (fr) * | 2023-06-23 | 2024-12-25 | Koninklijke Philips N.V. | Dispositif fluidique et son utilisation |
WO2024261021A1 (fr) | 2023-06-23 | 2024-12-26 | Koninklijke Philips N.V. | Dispositif fluidique et son utilisation |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Díaz‐González et al. | Recent advances in electrochemical enzyme immunoassays | |
Bange et al. | Microfluidic immunosensor systems | |
WO2005095262A1 (fr) | Microcircuit integre et procede de detection de molecules et d'interactions moleculaires | |
JP4216712B2 (ja) | マイクロ流体式化学検定装置および方法 | |
CN104203808B (zh) | 具有纳米结构电极的生物传感器 | |
JP5043186B2 (ja) | 微細流路型センサー複合構造物 | |
US6878539B1 (en) | Affinity sensor for detecting specific molecular binding events and use thereof | |
JP2006516721A (ja) | 多孔質層上に試薬を含む複層化された電気化学系微小流体センサー | |
US20110076783A1 (en) | Multi-dimensional fluid sensors and related detectors and methods | |
US20020127740A1 (en) | Quantitative microfluidic biochip and method of use | |
JPWO2005090972A1 (ja) | 生物学的物質の分析キット、分析装置及び分析方法 | |
JP2004132954A (ja) | 一個または複数個の分析物を検出するための方法および装置、ならびに装置の使用 | |
Díaz‐González et al. | Diagnostics using multiplexed electrochemical readout devices | |
JP5766714B2 (ja) | インピーダンス測定に基づく多重インピーダンス解析システムを使用する方法 | |
US9863941B2 (en) | Microchip and method for detecting molecules and molecular interactions | |
US20080081332A1 (en) | Methods and devices for conducting diagnostic testing | |
EP1933138A1 (fr) | Substrat d'essai biologique et procédé et dispositif de production d'un tel substrat | |
US8067249B2 (en) | Method for functionalizing biosensor chips | |
US20080311679A1 (en) | Biosensor Device | |
KR100598375B1 (ko) | 바이오 물질의 특성 측정 시스템 및 방법 | |
US10329396B2 (en) | Process for immobilizing one or more receptor biomolecules on one or more solid surfaces | |
JP5522515B2 (ja) | 電気化学分析チップ | |
US20040110230A1 (en) | Method for determining concentrations of analytes | |
JP2007263706A (ja) | バイオアッセイ用マイクロチップ | |
KR100772519B1 (ko) | 생체분자 검출용 센서, 그를 포함하는 생체분자 검출 장치,및 그를 이용한 생체분자 검출 방법 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DPEN | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 11547405 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWW | Wipo information: withdrawn in national office |
Country of ref document: DE |
|
122 | Ep: pct application non-entry in european phase |