A kind of micro-fluidic chip of multiple determinationTechnical field
The present invention relates to microfluidic chip analysis field, particularly relate to a kind of micro-fluidic chip of multiple determination.
Background technology
Micro-fluidic chip, also known as chip lab, refers to a kind of biological or chemical laboratory built on the chip of a piece several square centimeters.It makes the component of micro-/ nano magnitude respectively the basic operation unit such as reaction, separation, cultivation, sorting, detection involved in biological and chemical field, be integrated on the chip of a piece very little, network is formed by microchannel, whole system is run through, in order to realize the various functions of standard biologic or chemistry with controlled fluid.The reaction such as the enzyme reaction carried out for the purpose of biological sample analysis, immune response, PCR reaction, ELISA all can realize on micro-fluidic chip.Because microfluidic chip technology has, sample size is little, integrated level is high, easily realize Automated condtrol and high throughput analysis, and the analysis sample pre-treatments of micro-fluidic chip carrying out biochemical reaction operation more conventional is more convenient, quick, with low cost.And what the biochemical reaction of high specific and micro-fluidic chip were powerful is separated, detectability combines and will demonstrate more significant advantage.
When application micro-fluidic chip carries out multi objective biochemistry detection, due to the diversity of Testing index, multiple reaction tank occurred for detection reaction need be arranged detect same sample on chip, how rapidly and efficiently multiple determination is carried out to sample while ensure that the sample size of independently carrying out and participating in each detection reaction of each detection reaction unanimously becomes the key link in micro-fluidic chip design.
Patent of invention CN102671729 discloses a kind of micro-fluidic chip for multi objective biochemistry detection, this chip comprises microfluidic channel, several reaction tanks and pneumatic micro valve, reaction tank internal fixtion has the reagent needed for biochemical reaction, and several reaction tanks are connected by microfluidic channel serial or parallel.Although this chip realizes the connected sum isolation between each reaction tank by the switch controlling pneumatic micro valve, but in the flow process of sample feeding, easily cause the cross pollution of reaction reagent, sample needs to flow through multiple connected reaction tank after injecting and each reaction tank could be full of, in passage, flow rate of liquid is each variant, there is larger difference in the sample size participating in each detection reaction between the reaction tank causing position different, is unfavorable for the accurate control of each detection reaction and the accurate analysis of testing result.
Based on above background, invent that a kind of structure is simple, the support multi objective of simple operation detects simultaneously, and there is not cross pollution between each index, the micro-fluidic chip that each reaction tank sample size is identical is very necessary.
Summary of the invention
The object of the present invention is to provide a kind of micro-fluidic chip of multiple determination, ensure to participate in the sample size of each detection reaction identical and independently between each Indexs measure reaction to occur without cross pollution simultaneously, realize multiple determination that is easy, efficient, low cost.
For achieving the above object, the present invention adopts following technical scheme:
A kind of micro-fluidic chip of multiple determination, comprise gas controlled passageway layer (100), organic high molecular polymer film (200), microfluidic channel layer (300), the integrated bonding sealing-in of layers of material forms chip structure, it is characterized in that: gas controlled passageway layer comprises the first half of sample holes (1), venthole (6) and two pneumatic micro valves (2,3) and multiple series connection liquid storage tank (4); Organic high molecular polymer film is provided with the hole of sample holes (1), pneumatic micro valve structure (2,3), liquid storage tank (4) and venthole (6) correspondence position size; The fluid passage (8) that microfluidic channel layer arranges multiple series connection liquid storage tank (4) the latter half and multiple reaction tank (9), be communicated with fluid passage (7) between each liquid storage tank (4), be communicated with liquid storage tank (4) and reaction tank (9).
Described two micro-valves (2,3) valve seat (10 is comprised, 12) and micro-valve gas channels (11,13), by controlling air pressure, micro-valve open and close is controlled, and then control flow direction in microfluidic channel layer, after outside air enters micro-valve, extruding intermediate layer film makes it protruding blocking lower channel, reaches control effects; Wherein micro-valve (2) tool valve seat (10) and multiple branches gas channels (11), passages intersect is located at above each liquid storage tank (4) interface channel, controls fluid passage (7) switch between each liquid storage tank (4); Micro-valve (3) tool valve seat (12) and gas channels vertical with it (3), intersecting is arranged on liquid storage tank (4) and reaction tank (9) interface channel (8), the switch of control connection passage (8).
Described pneumatic micro valve (2,3) valve seat (10) can be connected with the outer source device such as gas bomb or syringe with (12), and then provides positive and negative pressure in described micro-valve gas channels (11) and (13).
Identical sized by described liquid storage tank (4), parallel series connection, fluid passage (7) is topmost accessed by it and picks out, and least significant end Connection Pool (5), stores excessive sample.
Described micro-fluidic chip material can select any one in glass, dimethyl silicone polymer (PDMS), polymethyl methacrylate (PMMA), PETG (PET) or Merlon (PC).
The material of the upper half side elastic film of described sample reservoir (4) can be dimethyl silicone polymer (PDMS), silicon rubber, memorial alloy or polytetrafluoroethylene (PTFE).
The reagent needed for multiple determination is fixed with in advance in described reaction tank (9), such as enzyme and substrate, antigen or antibody and PCR primer etc., the mode such as can be fixed by physical absorption, chemical crosslinking, sol-gel embedding, microballon or film is fixing is fixed.
A method of work for micro-fluidic chip as claimed in claim 1, is characterized in that comprising the steps:
Step one: during application of sample, micro-valve (2) is opened, and micro-valve (3) cuts out.In micro-valve gas channels (13), pass into gas-pressurized by valve seat (12), close liquid storage tank to reaction tank direction fluid passage.Sample injects from sample holes (1), and sample flows through fluid passage (7) and flows in each sample liquid storage tank (4), and unnecessary sample flows in Sample Buffer pond (5).
Step 2: when each sample liquid storage tank (4) is all full of, micro-valve (2) cuts out, micro-valve (3) is opened, in micro-valve gas channels (11), gas-pressurized is passed into by valve seat (10), micro-valve of fluid passage (7) interior liquid flow between each liquid storage tank of closing control (4), realizes the isolation between each sample liquid storage tank (4); Open the micro-valve controlling each sample liquid storage tank and the fluid passage of corresponding reaction tank, the elastic film of pressing each sample liquid storage tank (4) top, make sample flow in corresponding reaction tank (9) from each sample liquid storage tank (4), sample flows into reaction tank (9) and reacts with the multiple determination reagent be fixed in advance in reaction tank (9) afterwards.
Beneficial effect
The invention provides a kind of micro-fluidic chip of multiple determination, based on microfluidic chip technology platform, integrate sample feeding, multiple determination, only need be incorporated into sampling device during detection and inject sample, utilize additional source of the gas to control the unlatching of micro-valve with closed, manual or other modes press chamber wall and can realize detecting, and structure is simple, easy to use, with low cost; The sample reservoir of multiple formed objects connected in series is utilized to make the sample size of each detection reaction of participation identical, sample storage is located at different regions from reaction, integrated pneumatic micro valve is utilized to make each reaction tank form independently conversion zone, avoid the reagent contamination that caused by liquid flow in sample feeding and course of reaction and mutually disturb, improve the precision participating in detection reaction sample size, ensure that the reliability of testing result.
Accompanying drawing explanation
Fig. 1 multiple determination chip overall schematic.
Top tank air control channel Rotating fields schematic diagram in Fig. 2 multiple determination chip.
Intermediate layer PDMS membrane structure schematic diagram in Fig. 3 multiple determination chip.
Lower floor's microfluidic channel Rotating fields schematic diagram in Fig. 4 multiple determination chip.
Overall structure composition schematic diagram in Fig. 5 multiple determination chip.
Micro-valve in Fig. 6 multiple determination chip opens and closes schematic diagram.
1 is sample holes, and 2 is liquid storage tank pneumatic micro valve, and 3 is reaction tank pneumatic micro valve, 4 is sample reservoir, and 5 is Sample Buffer pond, and 6 is venthole, 7 is liquid storage tank fluid passage, and 8 is reaction tank fluid passage, and 9 is reaction tank, 10 is the micro-valve base of liquid storage tank, the micro-valve gas channels of 11 liquid storage tank, and 12 is the micro-valve base of reaction tank, 13 is the micro-valve gas channels of reaction tank, 100 is gas controlled passageway layer, and 200 is organic high molecular polymer film, and 300 is microfluidic channel layer.
Detailed description of the invention
The present invention will be further described for example below, and this example is only one of embodiment of apparatus of the present invention, does not make any restriction to the present invention.
Embodiment one: microfluidic chip structure
As shown in Fig. 1,2,3,4,5: a kind of micro-fluidic chip detected for many biochemical indicators, formed by the chip material bonding sealing-in being integrated with micro-valve, comprise gas controlled passageway layer 100, organic high molecular polymer film 200, microfluidic channel layer 300, wherein:
Gas controlled passageway layer 100 is provided with the first half of sample feeding hole 1, venthole 6, two pneumatic micro valves 2,3 and multiple series connection sample reservoir 4, and the side of the first half of sample reservoir 4 is elastic film and is exposed in air;
Microfluidic channel layer 300 comprise be communicated with sample holes and each sample liquid storage tank fluid passage 7, be communicated with the fluid passage 8 of each sample liquid storage tank with corresponding reaction tank, the latter half of sample reservoir, the Sample Buffer pond 5 be communicated with sample injection channel end and reaction tank 9, reaction tank internal fixtion has the reaction reagent of multiple determination;
Organic high molecular polymer film 200 is sandwiched between gas controlled passageway layer 100 and microfluidic channel layer 300, and on film, the position of corresponding sample holes 1, valve seat 10 and 12, venthole 6 and sample reservoir 4 is provided with the hole of corresponding size;
Above-mentioned in the micro-fluidic chip of multiple determination, the material of described micro-fluidic chip is the one in PC, PDMA, PMMA, PET, the present embodiment the selection of material is PC, the thickness of control channel layer is 3 ~ 5mm, and the thickness of fluid passage layer is 120 ~ 180um (can change different-thickness size according to actual conditions);
Above-mentioned in the micro-fluidic chip of multiple determination, described sample reservoir 4 the first half sidewall the material of elastic film be silicon rubber, PDMS, one in memorial alloy or polytetrafluoroethylene (PTFE), the present embodiment selects silicon rubber, and the thickness of elastic film is 60 ~ 100um;
Above-mentioned in the micro-fluidic chip of multiple determination, the valve seat 2 of described pneumatic micro valve 12 is connected with gas syringe with 11, and then gas-pressurized can be passed in described micro-valve gas channels 3 and 10, make film 14 that elastic deformation occur, the thickness of film is 60 ~ 100um;
Above-mentioned in the micro-fluidic chip of multiple determination, be fixed with the enzyme needed for detecting for 4 kinds of biochemical indicators and substrate in described 4 reaction tanks 9 respectively in advance;
The cross section of sample holes is circular, and diameter is 0.75mm; The face, rank street of venthole is circular, and diameter is 0.3mm; The cross section of sample reservoir is circular, and diameter is 7.5mm, is highly 0.2mm; The cross section of reaction tank is oval, and diameter is 15mm × 8mm, is highly 0.2mm; Sample Buffer pond is rectangle, long 10mm, wide 6mm, is highly 0.2mm; Fluid passage height 100um, wide 300um, cross section is semicircle; Gas controlled passageway height 100um, wide 300um, cross section is semicircle, and above-mentioned data are only limitted to the present embodiment, and the present invention is not limited to data in the present embodiment, and data suitably can adjust change according to actual conditions in other embodiments.；
Embodiment two: micro-fluidic chip workflow
Step one: during application of sample, micro-valve 2 is opened, micro-valve 3 cuts out, in micro-valve gas channels 13, gas-pressurized is passed into by valve seat 12, close liquid storage tank to reaction tank direction fluid passage, sample injects from sample holes 1, and sample flows through fluid passage 7 and flows in each sample liquid storage tank 4, and unnecessary sample flows in Sample Buffer pond 5;
Step 2: when each sample liquid storage tank 4 is all full of, micro-valve 2 cuts out, and micro-valve 3 is opened, and passes into gas-pressurized by valve seat 10 in micro-valve gas channels 11, in each liquid storage tank of closing control 4 fluid passages 7, micro-valve of liquid flow, realizes the isolation between each sample liquid storage tank 4; Open the micro-valve controlling each sample liquid storage tank and the fluid passage of corresponding reaction tank, elastic film above pressing each sample liquid storage tank 4, make sample flow in corresponding reaction tank 9 from each sample liquid storage tank 4, react with the multiple determination reagent be fixed in reaction tank 9 in advance after sample flows into reaction tank 9.
Embodiment three: facture of microchip method
(1) preparation has the mould of micro-structural on micro-fluidic chip
By microchannel and the micro-structural of computer aided design software design micro-fluidic chip, make the mask of gas controlled passageway layer and microfluidic channel layer respectively according to design drawing chromium plate.
Select silicon chip to carry out chemical etching and make mould, first, Wafer Cleaning is clean, be put on sol evenning machine after the silicon chip nitrogen cleaned up dries up, getting appropriate photoresist is applied on silicon chip, start sol evenning machine and get rid of resist coating, mask plate is placed in and the silicon chip scribbling photoresist is placed on litho machine exposes, through development and after dry technique after utilize dry etching to obtain the mould of the micro-structural with top tank air control channel layer and lower floor's microfluidic channel layer.
(2) pressure sintering makes chip
A kind of (the present embodiment selects PC) in PDMS, PMMA, PET, PC sheet material is cut into small pieces by die size, clean, oven dry is placed on mould, at 180 DEG C on hot press, add 1000lb pressure 4.5min, the demoulding, the respectively obtained PC chip with microfluidic channel and gas controlled passageway.
(3) ratio being 10:1 by volume by (the present embodiment uses PDMS) performed polymer a kind of in dimethyl silicone polymer (PDMS), silicon rubber, memorial alloy or polytetrafluoroethylene (PTFE) and curing agent mixes, mixed liquor is watered with on several, the glass of chip formed objects, heat up crosslinked after 2 hours, the thickness forming good springiness is the PDMS film of 80um.
(4) ultrasonic drilling is carried out in the relevant position on the top tank air control channel layer obtained in step (two) with ultrasonic drilling machine and lower floor microfluidic channel layer PC chip, obtain sample holes, valve seat and venthole, step (three) obtained PDMS film on ultrasonic drilling, obtain the hole identical with sample holes, sample reservoir and venthole position size.
(5) chip of PC up and down that step (four) obtains puts into plasma cleaner vacuum bombardment 1min, the reagent of each reaction is loaded in reaction tank rapidly on lower floor's microfluidic channel layer, rapidly the PDMS that step (four) obtains is placed between top tank air control channel layer and lower floor's microfluidic channel layer, the PDMS film that step (three) obtains is cut to diameter and is greater than sample reservoir size, be placed in the correspondence position on top tank air control channel layer, carry out the micro-fluidic chip that irreversible sealing-in obtains being integrated with micro-valve.