JP7202820B2 - microfluidic chip - Google Patents

Description

TECHNICAL FIELD The present invention relates to a microfluidic chip that enables rapid reaction between a specimen and a plurality of reagents and highly accurate analysis without causing contamination.

A microfluidic chip is a device that performs processes such as mixing, reaction, extraction, and separation using microfluidic channels processed on the chip. It is characterized by being able to culture and observe cells and microorganisms that have been difficult to handle in the past.
Patent Literature 1 discloses a microchannel chip having a function of moving a liquid to be measured (specimen) to a target location by applying pressure. According to this, since the specimen is forcibly sucked by suction pressure and moved to the analysis part, even a small amount of specimen can be introduced into the analysis part in a short time and analyzed regardless of its viscosity, etc. As a result, for example, when performing analysis using reagents, it is possible to make the reaction time and amount of the sample and the reagent constant. The document also describes a technique for selectively transporting liquid by providing a difference in liquid resistance between the bypass flow path and the suction flow path.

JP-A-10-132712

Generally, it is not uncommon to observe the state of bacteria or cells cultured in sample analysis. When culturing, typically, the chip holding the specimen is placed in an incubator kept under constant conditions (e.g., room temperature or higher temperature, approximately 100% humidity) for a certain period of time (e.g., 2 hours or more). ) storage method is used.
However, with the sample analysis tool disclosed in Patent Document 1, it is difficult to keep the chip in the incubator while maintaining the suction pressure of the suction pressure generation chamber so as to retain the sample in the analysis section.
Conversely, when the vacuum pressure in the vacuum chamber is released in order to store the chip in the incubator, the sample may be drawn into the vacuum chamber, resulting in contamination of the reaction solution. In particular, in the case of so-called multi-analysis, in which a plurality of reactions are simultaneously carried out on a single microchannel chip, the disadvantages are conspicuous. That is, in the case of the sample analysis tool for multi-analysis in Patent Literature 1, the flow path has a structure in which the flow path branches off from a single suction portion at the suction flow path and rejoins at the suction pressure generation chamber. In multi-analysis, separate reagents are placed in each analysis unit, but with this structure, the components of the reagents go back and forth (merge) in the suction channel via the suction pressure generation chamber, causing contamination. Probability is high. This is the same even if the bypass channel is arranged, and the liquid in the suction channel after the reaction and the liquid in the bypass channel are mixed in the suction pressure generation chamber, which adversely affects the reliability of the analysis results. may affect
In view of the above, it is an object of the present invention to provide a new structure in which each reaction liquid does not cause contamination when multiple analyzes are performed on a single microchannel chip.

That is, the present invention includes the following.
[1] a test liquid inlet;
a plurality of reaction units in which a drug that reacts with the test liquid is placed in at least one of the test liquid introduction ports;
a first channel connecting the test liquid inlet and each of the plurality of reaction sections;
one aspirating part for aspirating a reaction liquid obtained by reacting the drug with the test liquid from each of the plurality of reaction parts;
A microchannel chip having a second channel connecting each of the plurality of reaction parts and the suction part, having a channel width narrower than that of the first channel, and having an observation region for observing the reaction solution.
[2] The microchannel chip according to [1], wherein the second channel has a confluence prevention mechanism for the reaction solution at or near the connecting portion with the suction portion.
[3] The confluence prevention mechanism is
a throttle section inlet having a wall surface substantially orthogonal to the flow direction of the reaction liquid; a throttle section outlet where the width of the second channel gradually increases toward the suction section;
The microchannel chip according to [2].
[4] The microchannel chip according to [1], wherein the observation area of the second channel has a size that allows simultaneous observation of a portion of the plurality of second channels.
[5] The first channel has a backflow prevention mechanism for the test solution near the reaction section,
The microchannel chip according to [1], wherein the liquid backflow prevention mechanism has a structure in which the width of the first channel gradually decreases from the test liquid inlet toward the reaction section.
[6] Any one of [1] to [4], wherein the second flow path has a non-observation area composed of a curved portion and a straight portion between the observation area and the suction portion The described microfluidic chip.
[7] The microchannel chip according to [6], wherein the non-observation region is formed in a spiral shape, and has the suction portion at a substantially central portion or an end thereof.

According to the present invention, it is possible to perform highly stable, reproducible, and highly efficient measurements using a plurality of reagents without causing contamination.

1 is a perspective view showing the configuration of a microchannel chip according to the present invention; FIG. FIG. 4 is a plan view of the first substrate rear surface 11b of the microchannel chip according to the present invention; 1 is a cross-sectional view showing one mode of use of a microchannel chip according to the present invention; FIG. FIG. 3 is an enlarged view of part A in FIG. 2 ; (a) It is the B section enlarged view of FIG. (b) It is a C section enlarged view of Fig.5 (a). FIG. 4 is a diagram showing the action of the backflow prevention mechanism 22 for the test liquid of the microchannel chip according to the present invention. FIG. 4 is a diagram showing the operation of the reaction liquid confluence prevention mechanism 23 of the microchannel chip according to the present invention. It is a second embodiment of the microchannel chip according to the present invention. It is a third embodiment of the microchannel chip according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the following embodiments.

[Configuration of microchannel chip]
A detailed description will be given below with reference to FIGS. 1 to 3. FIG.
The exemplified multi-analytical microchannel chip has a substrate on which a test liquid introduction port 13, a drug introduction port 14, and a suction portion 18 are formed with openings on the surface thereof, and a drug sample provided on the bottom surface of the drug introduction port 14. Micrometer (μm)-level fine communication channel (first channel 16) for communicating between the holding part (reaction part) 15 and the test liquid introduction port, and between the reaction part 15 and the suction part 18 A fine communication channel (second channel 19) of a micrometer (μm) level for communicating is formed inside the substrate. The test liquid introduced from the test liquid introduction port 13 is fed through the first channel 16 to the drug arranged in the drug holding portion 15, thereby bringing the drug and the test liquid into contact with each other. Thereby, the drug and the test liquid are reacted to obtain a reaction liquid. An observation region 21 is provided in the middle of the second flow path 19 that guides the reaction liquid to the aspirator 18, and sensitivity evaluation of the test liquid can be performed.

A microchannel chip 10 shown in FIG. 1 is formed by bonding together a first substrate 11 on the front side and a second substrate 12 on the back side. A microchannel is formed by a groove formed in the rear surface 11b of the substrate 11 and the substrate 12 bonded to the substrate 11 .

As shown in FIGS. 1 and 3, the first substrate 11 is formed with a through hole passing through the front surface 11a and the rear surface 11b, and this through hole functions as the test liquid introduction port 13. . A through-hole is also formed at a position slightly away from the test liquid introduction port 13 , and this through-hole functions as a drug introduction port 14 . Regarding the first substrate 11, the surface on which the test liquid introduction port 13, the drug introduction port 14, and the later-described suction unit 18 are opened to the outside is defined as the surface 11a, and the bonding surface to which the second substrate 12 is adhered is defined as the back surface 11b. . The surface 11 a is the surface of the microchannel chip 10 .

As shown in FIG. 3 , the portion of the second substrate 12 facing the drug introduction port 14 , that is, the bottom surface of the drug introduction port 14 constitutes a drug holding portion 15 , and the drug holding portion 15 contains the test liquid. composes the reaction part of

As shown in FIGS. 2 and 3, the back surface 11b of the first substrate 11, that is, the bonding surface, is provided with a test liquid inlet 13, a plurality of reaction sections 15, and the test liquid inlet 13 and the reaction sections 15, respectively. A concave groove is formed for forming a first flow path 16 (first flow path) that allows the flow to flow. A branching portion 17 communicating with the test liquid inlet 13 is provided in the first channel 16, and the first channel 16 branches into a plurality of channels downstream of the branching portion 17 and communicates with each of the reaction portions 15. there is When the second substrate 12 is bonded to the bonding surface of the first substrate 11, the concave groove of the first substrate 11 and the second substrate 12 form such a first flow at the interface between the substrates (inside the microchannel chip 10). A path 16 is formed.

It is preferable that a test liquid backflow prevention mechanism 22 is provided near the reaction section 15 of the plurality of first channels 16 and on the side of the test liquid introduction port 13 . FIG. 4 is a plan view showing an enlarged portion A in the vicinity of the reaction section 15 shown in FIG. The introduction port 13 communicates with the branch portion 17 of the first flow path 16, and has a tapered throttle portion inlet 31a whose width narrows from the upstream end toward the downstream side, and a substantially constant width communicating with the throttle portion inlet 31a. The narrowed portion 31b is connected to a narrowed portion outlet 31c having a wall surface substantially orthogonal to the flow direction of the reaction liquid. Normally, the width of the further upstream portion of the throttle inlet 31a is substantially the same as the width of the downstream end of the throttle outlet 31c.

Here, the test liquid that has flowed in from the test liquid introduction port 13 and passed through the branch 17 is guided toward the reaction section 15 through the throttle section inlet 31a, the throttle section 31b, and the throttle section outlet 31c. As a result, as shown in FIG. 6, which is an enlarged view of section D in FIG. to the test liquid introduction port 13, that is, the occurrence of liquid return is prevented. The structure of the backflow prevention mechanism 22 is not limited to this, and may be a conventional backflow prevention mechanism. may have.

Further, as shown in FIGS. 1 and 3, the first substrate 11 is further formed with through-holes penetrating the front surface 11a and the back surface 11b. It has a function as a suction part 18 for sucking a reaction liquid obtained by reacting a drug and a test liquid from each of them.

As shown in FIGS. 2 and 3, on the back surface 11b of the first substrate 11, that is, on the joint surface, there are four communication channels 19 (second channel ) is formed. The second channel 19 has an observation area 21 for observing the reaction liquid. The plurality of second channels 19 are designed to have channel widths so that part of the plurality of second channels can be observed within a single field of view, so efficient observation is possible. Further, by making the channel width of the second channel 19 narrower or shallower than the channel width of the first channel 16, the test liquid 3 is quickly introduced into the reaction section 15 when the test liquid 3 is introduced. , unexpected intrusion of the reaction liquid 5 into the second channel 19 can be prevented during the reaction.

Furthermore, it is preferable that each of the plurality of second flow paths 19 is provided with a reaction liquid confluence prevention mechanism 23 at a connecting portion with the suction portion 18 or in the vicinity thereof. For example, as shown in FIGS. 5A and 5B, the confluence prevention mechanism 23 includes a throttle inlet 31a having a wall surface substantially orthogonal to the flow direction of the reaction liquid, and a width is composed of a constricted portion outlet 31c where is gradually increased. FIG. 7 is a diagram (photograph) of an experiment on the state of the reaction liquid when actually sucking the reaction liquid from the suction unit 18 (the portion visible in gray in FIG. 7). It can be seen that the reaction liquids in the plurality of second flow paths 19 do not merge due to suction and exist independently in each of the second flow paths 19 . By providing a narrowed portion in a part of the channel in this way, it is possible to prevent the reaction liquids sucked by the suction portion 18 from being mixed (merged), and it is possible to perform observation (determination) with high accuracy. In addition, the structure of the confluence prevention mechanism 23 is not limited to this. A chemical blocking method using the surface energy difference between the liquid and the solid is adopted, such as blocking or providing a water-repellent part on the inner surface of the flow path to prevent the flow of the test liquid (water system). can also

In each of the plurality of second flow paths 19, as shown in FIG. 8, a non-observation area 24 composed of a bent portion and a straight portion is provided between the observation area 21 and the suction portion 18. can also The non-observation area 24 also has a function of preventing the reaction liquids from merging. As shown in FIG. 9, the non-observation area 24 may be formed in a spiral shape and designed to have a suction portion 18 approximately in the center or at the end thereof.

By the way, the transparency of the first substrate 11 is advantageous for observing changes in the test solution, confirming the amount of drug in the drug holding portion, checking the state of reaction between the drug and bacteria (evaluation of drug susceptibility to be described later), etc. preferable. Moreover, the first substrate 11 preferably has rubber elasticity. Furthermore, it is also preferable that the first substrate 11 has gas permeability. It preferably has gas permeability at least higher than that of natural rubber. This is to prevent breakage of the microchannel chip due to expansion of the gas due to heating by releasing air that inevitably remains sandwiched between the first substrate and the second substrate when they are attached to each other. is expected. Here, preferred materials having rubber elasticity have a tensile strength of 40-100 kg/cm ² and an elongation of 50-500% as measured according to JIS K6251:2010. Examples of rubbers having the physical properties described above include silicone rubbers, and polydimethylsiloxane is particularly recommended. Polydimethylsiloxane has a tensile strength of 70-100 kg/cm ² and an elongation of 100-500% as measured according to JIS K6251:2010, and these ranges are particularly preferred.

Moreover, the second substrate 12 may be a substrate commonly used in microchannel chips. Materials include, for example, glass, silicon, organic polymers, and glass/organic polymer composites. Glass is particularly suitable.

In this way, the test liquid inlet and
a plurality of reaction units in which a drug that reacts with the test liquid is placed in at least one of the test liquid introduction ports;
a first channel connecting the test liquid inlet and each of the plurality of reaction sections;
one aspirating part for aspirating a reaction liquid obtained by reacting the drug with the test liquid from each of the plurality of reaction parts;
a second channel that connects each of the plurality of reaction parts and the suction part, has a channel width narrower than that of the first channel, and has an observation area for observing the reaction solution;
A microchannel chip having

[Method for producing microchannel chip]
Next, a procedure for producing a microchannel chip will be described with reference to the drawings.
As shown in FIG. 1, the back surface 11b of the first substrate 11 is formed with a test liquid introduction port 13, a drug introduction port 14, a through hole forming a suction portion 18, a first channel 16, a second channel 19, and the like. Then, the second substrate 12 is adhered to the rear surface 11b, and the microchannel chip 10 is produced.

[Preparation of first substrate]
As described above, the material of the first substrate 11 is not particularly limited, but it is preferably a transparent material, preferably has rubber elasticity, is preferably gas-permeable silicone rubber, and is particularly preferably polydimethylsiloxane. When a material having rubber elasticity is used as the first substrate 11, the first substrate 11 and the second substrate 11 can be attached to each other simply by placing the first substrate 11 on the second substrate 12, without using an adhesive or the like. Twelve laminations can be made.

In order to manufacture the first substrate 11, first, a mold provided with concave grooves forming the first flow path 16, the second flow path 19, etc. is prepared, and liquid uncrosslinked silicone rubber, which is the raw material of the substrate 11, is prepared. Pour into this mold and let it harden. As a result, a rectangular substrate 11 made of silicone rubber is obtained in which concave grooves forming the first flow path 16, the second flow path 19, and the like as shown in FIG.

Subsequently, after the substrate 11 made of silicone rubber is removed from the mold, the portion of the substrate 11 corresponding to one end of the first channel 16 is processed to form the test liquid inlet 13 . Similarly, the drug introduction port 14 is formed by processing the portion of the substrate corresponding to the other end of the first flow path 16, and the suction portion 18 is formed by processing the portion of the substrate corresponding to the end of the first flow path 19. formed respectively. Note that these may be formed at the same time when the substrate 11 is molded using a mold.

The first substrate 11 has, for example, a long side of 50 mm, a short side of 40 mm, and a thickness of 2 mm. The width of the groove forming the first flow path 16 is about 300 μm, and the width of the groove forming the second flow path 19 is about 50 μm. The inner diameter of the test liquid inlet 13 is about 1 mm, the inner diameter of the drug inlet 14 is about 1 mm, and the inner diameter of the suction portion 18 is about 1 mm. The structure as shown in FIG. 2 can be collectively formed by fine processing using a photomask.

As described above, the microchannel chip for multi-analysis of the present exemplary embodiment has a configuration in which a total of 12 reaction units 15 are provided in the microchannel chip 10. 10 can be provided. In the example, four reaction sections 15 and corresponding number of first flow paths 16 and second flow paths 19 are provided for one test liquid inlet 13 as one set. The number of sets of the test liquid inlet, the reaction section, the first channel and the second channel can be any number. It is sufficient to provide one suction unit 18 for one or more sets of the test liquid inlet, the reaction unit, the first flow channel, and the second flow channel, but a plurality of suction units are provided on the substrate. 18 and a corresponding number of sets of test liquid inlets, reaction sections, first channels and second channels.

[Preparation of second substrate]
The second substrate 12 may be a substrate that is commonly used in microchannel chips, but a glass substrate will be described below as an example.

[Lamination of first substrate and second substrate]
By bonding the second substrate 12 to the rear surface 11b of the first substrate 11 produced as described above, the microfluidic chip 10 is produced as shown in FIG.

In addition, it is preferable that the first substrate 11 and the second substrate 12 are formed of a transparent material, and the first channel 16, the second channel 19, etc. formed inside the microchannel chip 10 can be visually observed from the outside. 1, the illustration of the first channel 16, the second channel 19, etc. is omitted.

[Introduction of chemicals]
Next, when the microchannel chip is used for the sensitivity evaluation test of the test liquid, the inner surface of the second substrate 12 exposed at the bottom of the drug holding portion (reaction portion) 15 shown in FIG. First, a drug is provided that is a reactant to be evaluated comparatively by a susceptibility test.

In order to dispose the drug in the predetermined drug holding portion (reaction portion) 15, the drug is prepared by dissolving it in a solvent such as water in advance, and then the liquid drug is introduced into the inside from the drug introduction port 14 using a microsyringe or the like. Dripping. After that, the solid medicine is fixed to the bottom portion 15 of the medicine introduction port 14 by evaporating the solvent of the medicine stored inside the medicine introduction port 14 .

[Affixing sealing film]
Since some drugs deteriorate when exposed to moisture or oxygen in the air, a sealing film (not shown) for closing the drug introduction port 14 is applied to the surface 11a of the microchannel chip 10 to which the drug is supplied to the drug holding portion 15. ) may be pasted. As a result, the drug introduction port 14 in which the drug is placed in the drug holding portion 15 is closed by the sealing film, and it is possible to manufacture a microchannel chip for market distribution comprising the microchannel chip 10 and the sealing film. can. Since the drug introduction port 14 is closed by the sealing film, even if the drug fixed to the drug holding portion 15 is separated from the drug holding portion 15, the drug is prevented from scattering outside from the drug introduction port 14. The sealing film may cover only the drug introduction port, may cover the entire area of a certain area including the drug introduction port, or may cover the entire substrate including the test liquid introduction port 13. . When a material having gas permeability is used as the sealing film, moisture and oxygen inside the drug introduction port 14 permeate through the sealing film, and the drying agent placed in the package for packaging the microchannel chip body is allowed to pass through the sealing film. Since it is adsorbed by an agent (not shown), deterioration of the agent can be prevented. Moreover, the sealing film is preferably made of the same material as the first substrate 11 and is transparent.

[How to use the microfluidic chip]
Next, the method of using the microchannel chip will be described using a sensitivity evaluation test as an example.
[Susceptibility evaluation test procedure]
In the microchannel chip for multi-analysis according to the present invention, a test solution can react with a plurality of drugs individually and can be compared and evaluated. FIG. 2 shows an example of a channel shape in which 12 kinds of medicines can be arranged by arranging three blocks branched into four from the introduction port 13 . At this time, by providing one inlet 13 for the test liquid and branching the flow path of the liquid, it is possible to evaluate the sensitivity of the test liquid to different drugs at the same time.

FIG. 3 is a cross-sectional view of the microchannel chip 10, showing the procedure for conducting a sensitivity evaluation test.
When the microchannel chip is used for a sensitivity evaluation test of a test liquid, a drug is supplied from the drug introduction port 14 to the bottom surface of the drug introduction port 14, that is, the drug holding portion (reaction portion) 15, and arranged in advance.
With the drug placed in the reaction section 15, the test liquid 3 is supplied from the test liquid inlet 13 as shown in FIG. 3(A). The test liquid 3 is, for example, a culture medium containing predetermined bacteria, and is supplied into the first channel 16 by a microsyringe or the like inserted into the test liquid inlet 13 . The introduced test liquid 3 is branched into a plurality of first channels 16 at the branching portion 17 and introduced into each of the reaction portions 15 . When the test liquid 3 flows through the first channel 16, the air in the first channel 16 is discharged to the outside through the drug introduction port 14, and the drug introduction port 14 functions as an exhaust port. After the introduction of the target amount, a buffer liquid or air that does not mix with the test liquid 3 is subsequently introduced from the inlet 13 . As a result, the test liquid 3 already introduced into the first channel 16 from the test liquid inlet 13 is branched into four fine first channels 16 through the branching portion 17, and flows through each of the first channels 16. It flows and is accommodated in each of reaction sections 15 . The first channel 16 has a considerably finer portion than the size of the test liquid inlet 13, and the microchannel chip 10 of the microchannel chip is tilted to allow the test liquid 3 to first flow under its own weight. Although it is difficult to flow into the channel 16, by forcing the test liquid 3 into the first channel 16 with a buffer liquid or air, it is possible to ensure contact of the test liquid with the drug. In addition, in the multi-analytical microchannel chip having a plurality of first channels 16, the test liquid 3 is evenly branched to each of the first channels 16. Therefore, in this respect as well, the transfer by supplying the buffer solution or air is possible. Fluids are useful.

As shown in FIG. 3(b), when the test solution 3 comes into contact with the drug fixed to the bottom of the drug introduction port 14, the drug dissolves in the test solution, and the active ingredient contained in the drug and the test solution 3 are separated from each other. A reaction is initiated with the bacteria. By maintaining this state under predetermined conditions (eg, room temperature or higher, approximately 100% humidity, 2 hours or longer), the susceptibility of the bacteria to the drug is assessed. If a plurality of different chemicals are used here, a plurality of different reaction liquids 5 can be obtained.

From the viewpoint of reliability of the test, it is desirable that each reaction liquid 5 stays in a predetermined place for the required time. may occur. When the backflow progresses to the inlet 13, contamination of each reaction liquid 5 occurs. This phenomenon is called a backflow phenomenon, and when the backflow phenomenon occurs, it becomes impossible to correctly evaluate the susceptibility of bacteria.
In order to prevent this backflow phenomenon, it is preferable to provide a liquid backflow prevention mechanism 22 as shown in FIG. In this case, the liquid backflow prevention mechanism 22 is installed in the first channel 16 between the test liquid inlet 13 and the reaction section 15 and closer to the reaction section 15 than the branch section 17 . As a specific method of this liquid backflow prevention mechanism 22, as shown in FIG. It is also possible to adopt a chemical barrier using the difference in surface energy between liquid and solid, such as providing a water-repellent portion on the inner surface of the channel to prevent the flow of water.

For example, as shown in FIG. 4, when each of the first flow paths 16 is provided with a narrowed portion 31b, the minimum opening area of the narrowed portion 31b is smaller than that of the reaction portion 15, so that the reaction liquid 5 in the reaction portion 15 The surface tension acting between the highly water-repellent (low wettability) material (silicone rubber) and the test liquid in the constricted portion 31b exceeds the force that tends to wet and spread toward the test liquid inlet 13 side. . As a result, as shown in FIG. 6, the test liquid 3 inside the first channel 16 can be prevented from flowing back to the test liquid inlet 13 side, so that the mixing of the test liquid 3 as described above can be prevented. It becomes possible.

In actual use, for example, a predetermined amount of the test liquid 3 is sucked up with a dropper, and the test liquid 3 is introduced by applying the dropper to the test liquid inlet 13 . After all of Test Liquid 3 has been introduced, continue to push the dropper and follow with air to ensure that Test Liquid 3 is in contact with the drug. Even if the amount of air introduced fluctuates to some extent, the above-described backflow prevention mechanism 22 prevents backflow of the test liquid 3 (FIG. 6), and a constant amount or more of the test liquid 3 can always be brought into contact with the drug. Therefore, highly reproducible measurements can be performed without requiring skill.

Furthermore, after the reaction has sufficiently progressed in the reaction section 15 , suction pressure is generated from the suction section 18 . As a result, the space from the reaction section 15 to the suction section 18, that is, the air in the second channel 19 including the observation region 21 is sucked and exhausted, and the reaction liquid 5 in the reaction section starts to move toward the suction section. As shown in FIG. 3C, after moving the reaction liquid 5 to the observation area 21, the reaction liquid 5 is observed and analyzed. For example, a culture solution in which cells and bacteria are dispersed is used as the test solution 3, reacted with additives and drugs in the reaction section, and held for several hours for culturing. By observing the observation area 21 with a microscope or the like, the effect of the additive or chemical can be obtained quickly and with high accuracy. Moreover, as shown in FIG. 2, it is desirable to improve the efficiency of observation and analysis by converging a plurality of second channels 19 and gathering observation areas 21 .

Furthermore, in terms of operability, the use of one suction unit 18 makes it possible to easily perform the suction operation. In addition, by making the second channel 19 narrower than the first channel 16, the test solution 3 is quickly introduced into the reaction section 15 when the test solution 3 is introduced, and the second channel 19 is introduced during the reaction. Unexpected intrusion of the reaction liquid 5 into 19 can be prevented. During subsequent suction, the air occupying the space from the reaction section to the suction section 18 is exhausted without resistance. , uniform movement of the reaction liquid 5 becomes possible.

It is preferable to provide a liquid confluence prevention mechanism 23 between the observation area 21 and the suction section 18 in the second channel 19, as shown in FIG. This makes it possible to suppress contamination between the reaction liquids in the second channel 19 due to excessive suction.

As a specific suction method, for example, when a small amount of air in the dropper is extruded and applied to the suction portion 18 as it is to loosen the pressure of the dropper, the reaction liquid in the reaction portion 15 moves toward the suction portion 18 . Even if the suction amount fluctuates to some extent, the reaction liquid 5 does not overshoot and cause contamination in the suction section due to the function of the liquid confluence prevention mechanism 23 described above (FIG. 7). Highly reproducible measurements can be performed.

Furthermore, in addition to FIG. 5, as shown in FIG. 8, by configuring a sufficiently long flow path structure between the observation region 21 and the suction section 18, the space from the reaction section to the suction section during suction can be reduced. After the air that occupies the space is quickly exhausted, the pressure inside the flow path reaches an equilibrium state before the reaction liquids are mixed, the intrusion of the reaction liquids is stopped, and the mixing of the reaction liquids can be suppressed.
Alternatively, as shown in FIG. 9, in order to save space, the second flow path 19 may be spirally arranged, and the suction portion 18 may be arranged substantially in the center or at the end of the spiral.

As described above, as shown in FIG. 2, three of the four drug holding portions 15 contain the same type of drug with different concentrations of the antibacterial component, or different types of drugs with different antibacterial components. When different medicines are arranged and no medicine is arranged in the remaining one medicine holding portion 15, the effects of the medicines can be comparatively evaluated on the basis of no medicine. Thus, susceptibility evaluation tests can be performed for three drugs with one test liquid.
Since the microchannel chip 10 shown in FIG. 2 is provided with a total of 12 drug holding portions 15, drugs having different drug effects can be placed in the three drug holding portions 15 in each channel. For example, the sensitivity evaluation test of the test solution to nine kinds of drugs can be performed at the same time.
Alternatively, when three types of drugs having the same efficacy are placed in the three drug holding portions 15 in each channel and a sensitivity evaluation test is performed, it is possible to evaluate the variation in the effects of the three types of drugs on the test solution. can.
Alternatively, if drugs having different drug effects are supplied to all of the drug holding portions 15 at a total of 12 locations, it is possible to perform a sensitivity evaluation test of the test liquid to 12 kinds of drugs.

As described above, the case where this microchannel chip is applied to the evaluation of susceptibility of bacteria to drugs has been described. It can be applied to the analysis and evaluation of objects.

According to the microchannel chip of the present invention, rapid reaction between a plurality of reagents and test solutions is possible without causing contamination, and highly efficient and highly accurate analysis can be realized without requiring skill.

3 test liquid 5 reaction liquid 10 microchannel chip 11 first substrate 11a front surface 11b rear surface 12 second substrate 13 test liquid introduction port 14 drug introduction port 15 drug holding portion (reaction portion)
16 First channel 17 Branching part 18 Suction part 19 Second channel 20 Chip body 21 Observation region 22 Test liquid backflow prevention mechanism 23 Reaction liquid merging prevention mechanism 24 Non-observation region 31a Constriction inlet 31b Constriction section 31c Constriction outlet

Claims (6)

a test liquid inlet;
a plurality of reaction units in which a drug that reacts with the test liquid is placed in at least one of the test liquid introduction ports;
a first channel connecting the test liquid inlet and each of the plurality of reaction sections;
one aspirating part for aspirating a reaction liquid obtained by reacting the drug with the test liquid from each of the plurality of reaction parts;
a second channel that connects each of the plurality of reaction parts and the suction part, has a channel width narrower than that of the first channel, and has an observation area for observing the reaction solution ;
The microchannel chip , wherein the second channel has a confluence prevention mechanism for the reaction solution at or near the connecting portion with the suction portion . The confluence prevention mechanism is
a constricted section inlet having a wall surface substantially perpendicular to the flow direction of the reaction liquid;
a constricted section outlet in which the width of the second flow path gradually increases toward the suction section;
have
The microchannel chip according to claim 1. The observation area of the second channel has a size that allows simultaneous observation of part of the plurality of second channels
The microchannel chip according to claim 1. The first flow path has a backflow prevention mechanism for the test solution in the vicinity of the reaction section,
The liquid backflow prevention mechanism has a structure in which the width of the first flow path gradually decreases from the test liquid inlet toward the reaction section.
The microchannel chip according to claim 1. The second flow path has a non-observation area composed of a curved portion and a straight portion between the observation area and the suction portion.
The microchannel chip according to any one of claims 1 to 3. The non-observation area is formed in a spiral shape, and has the suction part at a substantially central part or an end thereof.
The microchannel chip according to claim 5.

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