Microfluidic chip for quantitative sampling

Abstract

The application relates to the technical field of quantitative sampling, in particular to a micro-fluidic chip for quantitative sampling, which comprises a rotating disc and a quantitative disc, the rotating disc is embedded in the quantitative disc, and the rotating disc rotates relative to the quantitative disc; a flow channel for sample storage and quantitative sampling of a sample to be measured is arranged on the quantitative disc; a gating channel is arranged on the rotating disc; through rotation of the rotating disc, the flow channel on the quantitative disc is switched between a sample storage state and a quantitative sampling state; the chip not only realizes high-precision quantitative sampling of a sample, but also has a simpler structure, a smaller overall size, is easy to integrate, avoids the problems of inconvenience in replacement and high cost of damaged parts of the device, and effectively prolongs the service life of the chip.

Description

Technical Field

[0001] This invention relates to the field of quantitative sampling technology, specifically to a microfluidic chip for quantitative sampling. Background Technology

[0002] Microfluidic chips are a hot topic in the development of micro total analysis systems. The goal of microfluidic chips is to integrate the functions of the entire laboratory, including sampling, dilution, reagent addition, reaction, separation, and detection, onto a single microchip that can be used multiple times.

[0003] Microfluidic chips require a six-way valve and a metering loop for quantitative sampling during injection. The six-way valve injector is an ideal injector in a high-performance liquid chromatography (HPLC) system, consisting of a circular sealing gasket and a fixed base. The working principle of the six-way valve injector is as follows: When the handle is in the sampling position, the sample is injected into the metering loop through a micro-injection needle via the injection port. After the metering loop is full, excess sample is discharged through the vent port. When the handle is rotated to the injection position, the valve connects to the liquid flow path, and the mobile phase delivered by the pump flushes the metering loop, propelling the sample into the HPLC column for analysis.

[0004] While existing injection methods can achieve high-precision sample measurement and are relatively convenient to use, they still have problems: the six-way valve injector has a complex structure and is too large, making it difficult to integrate into a microfluidic system, which is not conducive to the miniaturization, portability and automation of the microfluidic system; moreover, when the handle of the six-way valve injector is between the sampling position and the injection position, the flow path is temporarily blocked, and the pressure in the flow path increases sharply. When it is turned to the injection position, the excessive pressure can easily cause damage to the column head, resulting in a short service life of the existing six-way valve, high maintenance and repair frequency and high replacement cost. Summary of the Invention

[0005] The purpose of this invention is to provide a microfluidic chip for quantitative sampling, thereby solving the problem mentioned in the background art that microfluidic chips need to be used in conjunction with a six-way valve and a quantitative loop for quantitative sampling, which makes it difficult for microfluidic systems to be miniaturized, portable, and integrated.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A microfluidic chip for quantitative sampling includes a turntable and a quantitative disk, wherein the turntable is fitted inside the quantitative disk and the turntable rotates relative to the quantitative disk;

[0008] The quantitative plate is equipped with a flow channel for the injection and storage of the sample solution to be tested and for quantitative sampling.

[0009] The turntable is equipped with a selection channel. By rotating the turntable, the selection channel enables the flow channel on the quantitative plate to switch between the sample storage state and the quantitative sampling state.

[0010] Further, the flow channel comprises a quantitative channel, one end of the quantitative channel is a sample inlet end, the sample inlet end of the quantitative channel is provided with an interface one communicating with the outside, the interface one communicates with a driving pump; the other end of the quantitative channel is a sample outlet end, the sample outlet end of the quantitative channel is provided with an interface two communicating with the outside, the interface two communicates with a sampling pump;

[0011] The flow channel further comprises a liquid storage channel, one end of the liquid storage channel is provided with a liquid inlet opening communicating with an external liquid storage device, the other end of the liquid storage channel selectively communicates with the sample inlet end of the quantitative channel through a gating channel;

[0012] When sampling, the liquid storage channel and the sample inlet end of the quantitative channel are conducted through the gating channel, the sample outlet end of the quantitative channel is idle and not conducted, at this time the flow channel is in a sample storage state; or, the rotary disc is rotated, the liquid storage channel, the quantitative channel and the gating channel are idle and not conducted, at this time the flow channel is in a quantitative sampling state.

[0013] Further, the flow channel further comprises a waste liquid channel, one end of the waste liquid channel is provided with a liquid overflow opening communicating with the outside, the other end of the waste liquid channel selectively communicates with the sample outlet end of the quantitative channel through a gating channel;

[0014] The gating channel is two, which are gating channel one and gating channel two, the gating channel one and the gating channel two are two circular arc channels with equal volumes, the gating channel one and the gating channel two are oppositely arranged on the rotary disc;

[0015] The liquid storage channel communicates with the sample inlet end of the quantitative channel through the gating channel one, the sample outlet end of the quantitative channel communicates with the waste liquid channel through the gating channel two, at this time the flow channel is in a sample storage state; or, the rotary disc is rotated, the gating channel two communicates with the sample outlet end of the quantitative channel, the sample outlet end of the quantitative channel communicates with the gating channel one, the liquid storage channel and the waste liquid channel are idle and not conducted, at this time the flow channel is in a quantitative sampling state.

[0016] Further, the flow channel further comprises a waste liquid channel, one end of the waste liquid channel is provided with a liquid overflow opening communicating with the outside, the other end of the waste liquid channel selectively communicates with the sample outlet end of the quantitative channel through a gating channel;

[0017] The gating channel is three, which are gating channel one, gating channel two and gating channel three, the gating channel one, the gating channel two and the gating channel three are three circular arc channels with equal volumes, the gating channel one, the gating channel two and the gating channel three are uniformly distributed on the rotary disc;

[0018] The liquid storage channel is communicated with the sample inlet end of the quantitative channel through the gating channel one, the sample end of the quantitative channel is communicated with the waste liquid channel through the gating channel two, and the gating channel three is empty and not conducted at this time, and the flow channel is in the sample storage state at this time; or the rotary disc is rotated, the gating channel three is communicated with the sample inlet end of the quantitative channel, the sample end of the quantitative channel is communicated with the gating channel two, the liquid storage channel, the waste liquid channel and the gating channel one are empty and not conducted at this time, and the flow channel is in the quantitative sampling state at this time.

[0019] Further, the quantitative disc comprises a quantitative disc substrate and a quantitative disc cover plate, the quantitative disc cover plate is bonded on the quantitative disc substrate, and the flow channel is a cavity between the liquid flow channel body arranged on the quantitative disc substrate and the quantitative disc cover plate;

[0020] The rotary disc comprises a rotary disc substrate and a rotary disc cover plate, the rotary disc cover plate is bonded on the rotary disc substrate, and the gating channel is a cavity between the liquid flow channel body arranged on the quantitative disc substrate and the quantitative disc;

[0021] The rotary disc is embedded in the quantitative disc as a whole, the positions and heights of the quantitative disc substrate and the rotary disc substrate correspond to each other, and the positions and heights of the quantitative disc cover plate and the rotary disc cover plate correspond to each other; the flow channel and the gating channel are switched between the sample storage state and the quantitative sampling state through the rotation of the rotary disc;

[0022] The liquid inlet and the overflow port are arranged on the surface of the quantitative disc cover plate, the liquid storage channel is communicated with the outside through the liquid inlet, and the waste liquid channel is communicated with the outside through the overflow port; the interface one and the interface two are arranged on the surface of the quantitative disc cover plate, the sample end of the quantitative channel is communicated with the outside through the interface one, and the quantitative channel is communicated with the sampling pump through the interface two.

[0023] Further, the volume of the quantitative channel is 3 μL-150 μL, and the volume of the liquid storage channel is greater than that of the quantitative channel.

[0024] Further, the port communication positions of the flow channel on the quantitative disc and the gating channel on the rotary disc are both labyrinth sealing structures.

[0025] Further, the rotary disc and the quantitative disc are provided with a limiting component, the limiting component comprises a spring, a positioning steel ball, a sample feeding positioning groove and a sample taking positioning groove, the quantitative disc is provided with a positioning hole, the spring and the positioning steel ball are arranged in the positioning hole, the spring is connected with the bottom of the positioning hole, and the positioning steel ball is arranged on the top of the spring; the sample feeding positioning groove and the sample taking positioning groove are arranged on the rotary disc, the sample feeding positioning groove and the sample taking positioning groove are both semispherical, the positioning steel ball is clamped in the sample feeding positioning groove or the sample taking positioning groove, the positioning steel ball is clamped in the sample feeding positioning groove, and the flow channel is in a sample feeding storage state; or the rotary disc is rotated, the positioning steel ball is clamped in the sample taking positioning groove, and the flow channel is in a quantitative sample taking state.

[0026] Further, the edge of the rotary disc cover plate is provided with an auxiliary sample feeding positioning groove and an auxiliary sample taking positioning groove, the sample feeding positioning groove and the sample taking positioning groove are arranged on the rotary disc substrate, the auxiliary sample feeding positioning groove is equal in size and corresponding in position to the sample feeding positioning groove, the auxiliary sample taking positioning groove is equal in size and corresponding in position to the sample taking positioning groove, the sample feeding positioning groove and the auxiliary sample feeding positioning groove form a semispherical groove as a whole, and the auxiliary sample taking positioning groove and the sample taking positioning groove form a semispherical groove as a whole.

[0027] Compared with the prior art, the present application has the following beneficial effects:

[0028] (1) The chip of the present application is provided with a rotary disc and a quantitative disc which rotate relatively, the quantitative disc is provided with a quantitative channel, the rotary disc is provided with a plurality of gating channels, the quantitative channel is gated with the rotary channel on the rotary disc, so that the quantitative channel realizes the switching of the sample feeding storage state and the quantitative sample taking state, and the high-precision quantitative sample taking of the sample liquid is realized; compared with the prior art quantitative sample taking device of the microfluid, the chip of the present application is made into an extremely thin and transparent quantitative sample taking chip based on the principle of the six-way valve, the overall size is small, and the chip is easy to integrate.

[0029] (2) The rotary disc and the quantitative disc are connected through a labyrinth sealing structure, so that the problem that the plunger tip is damaged due to excessive pressure generated by rotation when the handle of the six-way valve feeder is between the sample taking position and the sample feeding position is avoided, the service life of the six-way valve is effectively prolonged, the frequency of maintenance and repair is high, the service life of the chip is effectively prolonged, the structure is simple, the damaged parts are easy to replace, and the replacement cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a sample feeding storage state structure diagram of the first embodiment of the present application;

[0031] Figure 2 It is a quantitative sample taking state structure diagram of the first embodiment of the present application;

[0032] Figure 3 It is a quantitative disc substrate structure diagram of the first embodiment of the present application;

[0033] Figure 4 The schematic diagram of the cover plate structure of the quantitative disc of the first embodiment of the present application;

[0034] Figure 5 The schematic diagram of the disc substrate structure of the first embodiment of the present application;

[0035] Figure 6 The schematic diagram of the cover plate structure of the rotating disc of the first embodiment of the present application;

[0036] Figure 7 The schematic diagram of the labyrinth seal structure of the present application;

[0037] Figure 8 The schematic diagram of the sample injection storage state structure of the second embodiment of the present application;

[0038] Figure 9 The schematic diagram of the quantitative sampling state structure of the second embodiment of the present application;

[0039] Figure 10 The schematic diagram of the quantitative sampling state structure of the third embodiment of the present application;

[0040] Figure 11 The schematic diagram of the quantitative sampling state structure of the fourth embodiment of the present application;

[0041] Figure 12 The schematic diagram of the quantitative sampling state structure of the fifth embodiment of the present application.

[0042] In the figure: 1, liquid inlet; 2, overflow port; 3, interface one; 4, interface two; 5, liquid storage channel; 6, waste liquid channel; 7, quantitative channel; 8, gating channel one; 9, gating channel two; 10, gating channel three; 11, spring; 12, positioning steel ball; 13, sample injection positioning groove; 14, sampling positioning groove, 131, auxiliary sample injection positioning groove; 141, auxiliary sampling positioning groove; 15, labyrinth seal structure; I, recess. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application.

[0044] Embodiment one:

[0045] Please refer to Figures 1 to 6The application provides a microfluidic chip for quantitative sampling, which comprises a rotating disc and a quantitative disc, the quantitative disc comprises a quantitative disc substrate and a quantitative disc cover plate, liquid flow channels for storing and sampling a sample liquid are arranged on the quantitative disc substrate, the quantitative disc cover plate is bonded to the quantitative disc substrate, and a cavity formed by the liquid flow channels and the quantitative disc cover plate is a flow channel; the rotating disc comprises a rotating disc substrate and a rotating disc cover plate, a plurality of liquid flow channels are arranged on the rotating disc substrate, the rotating disc cover plate is bonded to the rotating disc substrate, and a cavity formed between the rotating disc cover plate and the liquid flow channels is a gating channel; the rotating disc is wholly nested in the center of the quantitative disc, the rotating disc and the quantitative disc are coaxial, the positions and heights of the quantitative disc substrate and the rotating disc substrate correspond to each other, the positions and heights of the quantitative disc cover plate and the rotating disc cover plate correspond to each other, and the rotating disc can rotate relative to the quantitative disc; the gating channel is switched between a sample storage state and a quantitative sampling state by rotating the rotating disc; and the rotating disc and the quantitative disc are sealingly connected, Figure 4 The annular ring at the quantitative disc I is a recess, which serves as a seat for the rotating disc; the quantitative disc and the rotating disc are both made of an organic polymer material, preferably poly (methyl methacrylate) (PMMA), which has the characteristics of toughness, hardness and easy machining, and has excellent biocompatibility and no contamination to biological cells, and is transparent and easy to observe.

[0046] The rotating disc and the quantitative disc are bonded by a hot-pressing method to form the flow channel and the gating channel: the quantitative disc cover plate is covered on the quantitative disc substrate, the rotating disc cover plate is covered on the rotating disc substrate, the two are moved into a heating chip, the temperature is raised, the organic polymer is glassified, pressure is applied between the two, and then the temperature is lowered, the pressure is removed and the chip is demolded, so that the quantitative disc cover plate is sealed to the quantitative disc substrate, the rotating disc cover plate is sealed to the rotating disc substrate, and the communication between the quantitative disc and the rotating disc is realized by a labyrinth seal structure 15 as shown in Figure 7 The labyrinth seal structure 15 is a plurality of annular seal teeth arranged around the quantitative disc and the rotating disc, a series of interception gaps and expansion cavities are formed between the teeth, and the sample medium produces a throttling effect when passing through the gaps in the labyrinth to achieve the purpose of leakage prevention; because there is a gap between the rotating disc and the quantitative disc of the labyrinth seal structure, there is no solid contact, no lubrication is required, and thermal expansion is allowed, which can adapt to high-temperature, high-pressure and high-rotation frequency occasions, and avoids the problem that the column head is damaged due to excessive pressure generated by rotation when the handle of the six-way valve sampler is rotated between the sampling position and the sampling position.

[0047] Please refer to Figure 3 and Figure 4As shown, three flow channels are opened on the quantitative disc substrate, including a liquid storage channel 5, a waste liquid channel 6 and a quantitative channel 7. The liquid storage channel 5, the waste liquid channel 6 and the quantitative channel 7 are all spirally arranged on the quantitative disc substrate. The liquid storage channel 5 is used for temporarily storing sample liquid which needs to be quantitatively taken. Therefore, the volume of the liquid storage channel 5 is greater than that of the quantitative channel 7. One end of the liquid storage channel 5 is in selective communication with the rotating disc, and the other end of the liquid storage channel 5 is provided with a liquid inlet 1 which extends to the quantitative disc cover plate and is in communication with an external liquid storage device.

[0048] The quantitative channel 7 is used for quantitatively taking sample liquid to be measured. The quantitative channel 7 has a sample inlet end and a sample outlet end. The quantitative channel 7 is in communication with the rotating disc through the sample inlet end and the sample outlet end. The rotation of the rotating disc enables the quantitative channel on the quantitative disc to switch between a sample storage state and a quantitative sampling state. An interface 1 and an interface 2 are arranged on the quantitative disc cover plate. The interface 1 is used for connecting with an external driving pump, and the interface 2 is used for connecting with an external sampling pump. The sample inlet end of the quantitative channel 7 can be in communication with the external driving pump through the interface 1. The other end of the quantitative channel 7 is the sample outlet end which can be in communication with the external sampling pump through the interface 2. When sampling, the driving pump and the sampling pump provide positive pressure at the interface 1 and the interface 2, so that the sample liquid to be measured flows along the flow channel. When sampling, the driving pump provides positive pressure for the sample liquid to be measured in the quantitative channel 7, and the sampling pump provides negative pressure for the sample liquid to be measured, so that the sample liquid to be measured is sampled and used. The volume of the quantitative channel 7 is 3 μL-150 μL, which can be further preferably 30 μL, 50 μL, 100 μL or 150 μL. In this embodiment, the volume of the quantitative channel 7 is preferably 150 μL. The volume of the quantitative channel 7 is the volume of the liquid which needs to be quantitatively taken. In practice, the minimum volume of the quantitative channel 7 can be set according to the required sample amount. When the microfluidic chip needs more sample liquid, the sample liquid can be taken multiple times through the quantitative channel 7.

[0049] One end of the waste liquid channel 6 is in communication with the rotating disc, and the other end of the waste liquid channel 6 is provided with an overflow port 2. The waste liquid channel 6 is used to show whether the quantitative channel 7 in the chip has been filled with liquid. If there is liquid in the waste liquid channel 6, it means that the liquid storage channel 5, the quantitative channel 7 and the waste liquid channel 6 are sequentially connected, and the quantitative channel 7 is filled with the sample liquid to be measured. The rotating disc can be rotated to switch the gating channel for sampling. The waste liquid channel 6 is provided to ensure that the sample liquid does not overflow and to avoid contamination of the chip. The overflow port 2 can conveniently remove the residual liquid in the waste liquid channel 6.

[0050] Please refer to Figure 5 and Figure 6As shown, three gating channels are arranged on the rotating disc, including gating channel one 8, gating channel two 9 and gating channel three 10, which are three circular arc channels with equal volume and same shape, and are uniformly distributed on the same circumferential surface of the rotating disc substrate; the rotating disc rotates to different positions relative to the dosing disc through the gating channels, so that the gating of the chip in the sample injection storage state or the quantitative sampling state is realized; the sample injection storage state is that the liquid storage channel 5, the gating channel one 8, the dosing channel 7 and the waste liquid channel 6 are sequentially connected; in the liquid injection state, the driving pump and the sampling pump provide positive pressure at the interface one 3 and the interface two 4, so that the sample liquid flows along the flow channel and does not overflow from the interface one 3 and the interface two 4; the sample liquid enters the chip from the liquid inlet 1, sequentially passes through the liquid storage channel 5, the gating channel one 8, the dosing channel 7 and the waste liquid channel 6, and when the sample liquid in the waste liquid channel 6 overflows, it indicates that the liquid storage channel 5, the dosing channel 7 and the waste liquid channel 6 are sequentially connected, at this time the dosing channel 7 is filled with a certain amount of sample liquid; the quantitative sampling state is that the gating channel three 10, the dosing channel 7 and the gating channel two 9 are sequentially connected, at this time the driving pump provides positive pressure for the dosing channel 7 at the interface one 3, and the sampling pump provides negative pressure at the interface two 4, so that the sample liquid enters the sampling pump from the interface two 4, at this time the liquid storage channel 5 is connected with the waste liquid channel 6, and this path is empty.

[0051] In combination Figure 3 and Figure 4 As shown, a limiting component is arranged between the rotating disc and the dosing disc, which includes a spring 11, a positioning steel ball 12, a sample injection positioning groove 13 and a sampling positioning groove 14; the position of the rotating disc contacting the dosing disc substrate is provided with a positioning hole, the spring 11 and the positioning steel ball 12 are arranged in the positioning hole, the spring 11 is connected with the bottom of the positioning hole, and the positioning steel ball 12 is arranged at the top of the spring 11; the sample injection positioning groove 13 and the sampling positioning groove 14 are semispherical, the diameters of the sample injection positioning groove 13 and the sampling positioning groove 14 are smaller than the diameter of the positioning steel ball 12, the sample injection positioning groove 13 and the sampling positioning groove 14 are 60° apart on the arc surface of the rotating disc, the positioning steel ball 12 can be clamped in the sample injection positioning groove 13 or the sampling positioning groove 14 by rotating 60°, the positioning steel ball 12 is clamped in the sample injection positioning groove 13, the flow channel is in the sample injection storage state, or the rotating disc is counterclockwise rotated by 60°, the positioning steel ball 12 is clamped in the sampling positioning groove 14, and the flow channel is in the quantitative sampling state; the limiting component not only limits the relative sliding between the rotating disc and the dosing disc, but also positions the angle of rotation of the rotating disc and the dosing disc.

[0052] Further optimization involves adding an auxiliary sample injection positioning groove 131 and an auxiliary sampling positioning groove 141. The auxiliary sample injection positioning groove 131 and auxiliary sampling positioning groove 141 are set along the edge of the turntable cover plate. The sample injection positioning groove 13 and the sampling positioning groove 14 are set along the edge of the turntable substrate. The auxiliary sample injection positioning groove 131 and the sample injection positioning groove 13 are equal in size and corresponding in position. The auxiliary sampling positioning groove 141 and the sampling positioning groove 14 are equal in size and corresponding in position. The sample injection positioning groove 131 and the auxiliary sample injection positioning groove 131 form a hemispherical groove, and the auxiliary sampling positioning groove 141 and the sampling positioning groove 14 form a hemispherical groove. The setting of the auxiliary sample injection positioning groove 131 and the auxiliary sampling positioning groove 141 facilitates the determination of the position of the turntable cover plate and the turntable substrate, and facilitates positioning when bonding the turntable substrate and the turntable cover plate.

[0053] The vulnerable components of the chip in this invention are the spring of the limiting chip and the positioning steel ball 12. Since the life of the spring is limited, the positioning steel ball 12 may not be accurately positioned, which may lead to inaccurate sample liquid data during quantification. However, the spring and positioning steel ball 12 are easy to replace and the cost is also lower.

[0054] In use, rotate the turntable to engage the positioning steel ball 12 within the hemispherical groove formed by the sample injection positioning groove 13 and the auxiliary sample injection positioning groove 131. This connects the liquid storage channel 5 to one end of the first selection channel 8, the other end of the first selection channel 8 to the sample injection end of the quantitative channel 7, and the sampling end of the quantitative channel 7 to the second selection channel 9. The third selection channel 10 remains empty. At this time, the chip of this invention is in the sample injection and storage state. Please refer to [link / reference]. Figure 1 The operator pumps a sufficient amount of the test liquid into the storage channel 5 through the inlet 1. Excess reagent flows into the waste liquid channel 6. When liquid enters the waste liquid channel 6, it indicates that the storage channel 5 and the quantitative channel 7 are sequentially connected, and the quantitative channel 7 is filled with the test liquid. At this point, the sampling is stopped. Then, the turntable is rotated 60° counterclockwise to switch to the quantitative sampling state for sampling. The positioning steel ball 12 is engaged in the hemispherical groove formed by the sampling positioning groove 14 and the auxiliary sampling positioning groove 141, so that the sampling end of the quantitative channel 7 is connected to the selection channel 3 10, and the sampling end of the quantitative channel 7 is connected to the selection channel 2 9. The storage channel 5 is connected to the waste liquid channel 6 through the selection channel 1 8. That is, the selection channels 1 8, 2 9, and 3 10 are all in an empty state. At this time, the chip of this invention is in the quantitative sampling state. Please refer to [link to relevant documentation]. Figure 2 At this point, the staff uses a drive pump to provide positive pressure to the quantitative channel 7 at interface 1 (3) and negative pressure at interface 2 (4), driving the liquid in the quantitative channel 7 to enter the sampling pump from interface 2 (4) to complete the sampling.

[0055] This invention's chip is based on the principle of a six-way valve. In the sample storage state, the sample liquid is injected into the storage channel 5 through the injection needle from the inlet 1. The sample liquid sequentially passes through the storage channel 5, the first selection channel 8, the quantitative channel 7, and the waste channel 6. When sample liquid enters the waste channel 6, it indicates that the storage channel 5 and the quantitative channel 7 are sequentially connected, and the quantitative channel 7 is filled with the liquid to be tested. At this time, the quantitative channel 7 is filled with a fixed amount of the sample liquid to be tested. When rotating to the sampling position, the quantitative sampling state is that the third selection channel 10, the quantitative channel 7, and the second selection channel 9 are sequentially connected. A driving pump provides positive pressure to the quantitative channel 7 at interface 1 3 and negative pressure at interface 2 4, driving the liquid in the quantitative channel 7 to enter the sampling pump from interface 2 4 for analysis, completing the sampling. However, compared to existing six-way valves, this invention's chip not only achieves high-precision quantitative sampling of the sample liquid to be tested, but also has a simpler structure, smaller overall size, and is easier to integrate. It also avoids the problems of inconvenient replacement and high cost after damage to easily damaged parts, effectively extending the chip's service life.

[0056] Both the drive pump and the sampling pump are preferably FLOW-EZ pressure pumps, suitable for high-precision and high-stability microfluidic injection. FLOW-EZ has extremely low response time and flow control stability. Compared with high-precision syringe pumps, FLOW-EZ has a significant advantage in flow control and no pulse response. At the same time, FLOW-EZ integrates a knob and display screen, making it convenient to use. The output pressure can be adjusted by rotating the knob, providing either positive or negative pressure to the microfluidic chip. The display screen can show parameters such as pressure setpoint, pressure output, and flow rate in real time. With the flow monitoring module, fluid control can be achieved, making operation simple and quick.

[0057] Example 2:

[0058] Please see Figure 8 and Figure 9 As shown, the present invention provides a second simplified microfluidic chip for quantitative sampling: three flow channels are formed on the quantitative disk substrate, including a liquid storage channel 5, a quantitative channel 7, and a waste liquid channel 6. One end of the quantitative channel 7 is a sample inlet, and the other end is a sampling end. One end of the liquid storage channel 5 is provided with a liquid inlet 1 connected to a liquid storage device, and the other end of the liquid storage channel 5 is selectively connected to the sample inlet of the quantitative channel 7 through a gating channel. One end of the waste liquid channel 6 is provided with an overflow port 2 connected to the outside, and the other end of the waste liquid channel 6 is selectively connected to the sampling end of the quantitative channel 7 through a gating channel. The quantitative disk cover is provided with interface 3 and interface 4. Interface 3 is used to connect to an external drive pump, and interface 4 is used to connect to an external sampling pump. The sample inlet of the quantitative channel 7 can be connected to the external drive pump through interface 3, and the other end of the quantitative channel 7 is the sampling end. The sampling end of the quantitative channel 7 can be connected to the external sampling pump through interface 4.

[0059] Two selection channels are set on the turntable, namely selection channel 8 and selection channel 9. Selection channel 8 is connected to interface 3, and selection channel 9 is connected to interface 4. When one end of the liquid storage channel 5 is connected to an external liquid storage device, and the other end of the liquid storage channel 5 is connected to the injection end of the quantitative channel 7 through selection channel 8, and the sampling end of the quantitative channel 7 is connected to one end of the waste liquid channel 6 through selection channel 9, the sample storage state is in progress. If liquid enters the waste liquid channel 6, it means that the liquid storage channel 5, the quantitative channel 7 and the waste liquid channel 6 are sequentially connected, and the quantitative channel 7 is filled with the liquid to be tested. At this time, the sample injection can be stopped, and then the turntable is rotated 180° clockwise to switch to the quantitative sampling state, so that the injection end of the quantitative channel 7 is connected to selection channel 9, the sampling end of the quantitative channel 7 is connected to selection channel 8, and interface 4 is connected to the sampling pump. The liquid storage channel 5 and the waste liquid channel 6 are empty and not connected. This is the quantitative sampling state.

[0060] In use, when the outlet of the first channel 8 is connected to the inlet of the quantitative channel 7, the sample to be tested enters the first channel through the inlet 1 of the storage channel 5 and enters the inlet of the quantitative channel 7 through the port connection of the first channel 8. The sampling end of the quantitative channel 7 is connected to the waste liquid channel 6 through the second channel 9. The chip of this invention is in the sample storage state. When the quantitative channel 7 is filled with the liquid to be tested, the excess liquid in the chip overflows from the overflow port 2 of the waste liquid channel 6, indicating that the sample injection needs to be stopped. Rotate the turntable 180° so that the second channel 9 is connected to the inlet of the quantitative channel 7 and the first channel 8 is connected to the sampling end of the quantitative channel 7. The chip is in the quantitative sampling state. The drive pump provides positive pressure to the quantitative channel 7 at the first interface 3 and the sampling pump provides negative pressure at the second interface 4. The sample liquid is driven to enter the sampling pump output from the second interface 4 and is ready for use.

[0061] Example 3: Please refer to... Figure 10 The four-channel chip quantitative sampling state structure shown in this embodiment differs from that in Embodiment 1 in that: the volume of the quantitative channel 7 is preferably 100μL, and four channels are set on the turntable substrate. The four channels are arc-shaped channels with equal volume and the same shape. The four channels are evenly distributed on the turntable substrate, facing each other in pairs. The two facing channels form a group. One group of channels is used for sample storage state, and the other group of channels is used for quantitative sampling state. When switching, the turntable needs to be rotated 90° to switch from sample storage state to quantitative sampling state.

[0062] Example 4: Please refer to... Figure 11The five-channel chip quantitative sampling state structure shown in this embodiment differs from Embodiment 1 in that: the volume of the quantitative channel 7 is preferably 50 μL; five channels are set on the rotating substrate, and the five channels are arc-shaped channels of equal volume and identical shape, evenly distributed on the rotating substrate; two opposite channels are selected as a group, one group is used for sample injection and storage, and the other group is used for quantitative sampling. Figure 9 As shown, during the switching process, the turntable needs to be rotated 72° to switch from the sample storage state to the quantitative sampling state.

[0063] Example 5: Please refer to... Figure 12 The six-channel chip quantitative sampling state structure shown in this embodiment differs from that of Embodiment 1 in that: the volume of the quantitative channel 7 is preferably 30 μL, and six channels are set on the turntable substrate. The six channels are arc-shaped channels with equal volume and the same shape. The six channels are evenly distributed on the turntable substrate, facing each other in pairs. Any two facing channels form a group, that is, there are three groups of channels in total. All three groups of channels can be used as sample storage state or quantitative sampling state. When switching, the turntable needs to be rotated 60° to switch from sample storage state to quantitative sampling state. Continuous rotation can realize continuous multiple sampling, which is convenient for multiple sampling of small doses of sample solution.

[0064] In practice, the chip of this invention can also be configured with multiple gated channels, which facilitates the design of the turntable rotation angle and the layout of each channel, and makes it convenient for each gated channel of the chip to connect with external devices, thereby facilitating the switching between the chip's quantitative sampling state and sample storage state.

Claims

1. A microfluidic chip for quantitative sampling, characterized in that: It includes a turntable and a metering disk, wherein the turntable is fitted inside the metering disk and the turntable rotates relative to the metering disk; The quantitative plate is equipped with a flow channel for the injection and storage of the sample solution to be tested and for quantitative sampling. The turntable is equipped with a gating channel. By rotating the turntable, the gating channel enables the flow channel on the quantitative plate to switch between the sample storage state and the quantitative sampling state. A limiting component is provided between the turntable and the quantitative plate. The limiting component includes a spring (11), a positioning steel ball (12), an injection positioning groove (13), and a sampling positioning groove (14). A positioning hole is opened on the quantitative plate. The spring (11) and the positioning steel ball (12) are set in the positioning hole. The spring (11) is connected to the bottom of the positioning hole, and the positioning steel ball (12) is set on the top of the spring (11). The injection positioning groove (13) and the sampling positioning groove (14) are set on the turntable. The injection positioning groove (13) and the sampling positioning groove (14) are both hemispherical. The positioning steel ball (12) is engaged in the injection positioning groove (13) or the sampling positioning groove (14). When the positioning steel ball (12) is engaged in the injection positioning groove (13), the flow channel is in the injection storage state. Alternatively, when the turntable is rotated, the positioning steel ball (12) is engaged in the sampling positioning groove (14), and the flow channel is in the quantitative sampling state. The flow channel includes a quantitative channel (7), one end of which is an injection end. The injection end of the quantitative channel (7) is provided with an interface 1 (3) that communicates with the outside, and the interface 1 (3) is connected to the drive pump. The other end of the quantitative channel (7) is a sampling end. The sampling end of the quantitative channel (7) is provided with an interface 2 (4) that communicates with the outside, and the interface 2 (4) is connected to the sampling pump. The flow channel also includes a liquid storage channel (5), one end of which is opened to connect with an external liquid storage device (1), and the other end of which is selectively connected to the injection end of the quantitative channel (7) through a gating channel. The flow channel also includes a waste liquid channel (6), one end of which is provided with an overflow port (2) connected to the outside, and the other end of the waste liquid channel (6) is selectively connected to the sampling end of the quantitative channel (7) through a gating channel; During sample injection, the injection ends of the liquid storage channel (5) and the quantitative channel (7) are connected through the gate channel, and the sampling end of the quantitative channel (7) is empty and not connected. At this time, the flow channel is in the sample injection storage state; or, when the turntable is rotated, the liquid storage channel (5), the quantitative channel (7) and the gate channel are all empty and not connected. At this time, the flow channel is in the quantitative sampling state.

2. The microfluidic chip for quantitative sampling according to claim 1, characterized in that: There are two selection channels, namely selection channel one (8) and selection channel two (9). Selection channel one (8) and selection channel two (9) are two arc-shaped channels with equal volume. Selection channel one (8) and selection channel two (9) are arranged opposite to each other on the turntable. The liquid storage channel (5) is connected to the sample inlet of the quantitative channel (7) through the first selection channel (8), and the sampling end of the quantitative channel (7) is connected to the waste liquid channel (6) through the second selection channel (9). At this time, the flow channel is in the sample storage state; or, by rotating the turntable, the second selection channel (9) is connected to the sampling end of the quantitative channel (7), and the sampling end of the quantitative channel (7) is connected to the first selection channel (8). The liquid storage channel (5) and the waste liquid channel (6) are both empty and not connected. At this time, the flow channel is in the quantitative sampling state.

3. The microfluidic chip for quantitative sampling according to claim 1, characterized in that: There are three selection channels, namely selection channel one (8), selection channel two (9) and selection channel three (10). Selection channel one (8), selection channel two (9) and selection channel three (10) are three arc-shaped channels with equal volume. Selection channel one (8), selection channel two (9) and selection channel three (10) are evenly distributed on the turntable. The storage channel (5) is connected to the injection end of the quantitative channel (7) through the first selection channel (8), and the sampling end of the quantitative channel (7) is connected to the waste liquid channel (6) through the second selection channel (9). At this time, the third selection channel (10) is empty and not connected, and the flow channel is in the state of sample storage; or the turntable is rotated, the third selection channel (10) is connected to the injection end of the quantitative channel (7), and the sampling end of the quantitative channel (7) is connected to the second selection channel (9). At this time, the storage channel (5), the waste liquid channel (6) and the first selection channel (8) are all empty and not connected, and the flow channel is in the state of quantitative sampling.

4. The microfluidic chip for quantitative sampling according to claim 2 or 3, characterized in that: The metering disc includes a metering disc substrate and a metering disc cover plate. The metering disc cover plate is bonded to the metering disc substrate. The flow channel is a cavity between a liquid flow tank on the metering disc substrate and the metering disc cover plate. The turntable includes a turntable substrate and a turntable cover plate. The turntable cover plate is bonded to the turntable substrate. The selection channel is a cavity between a liquid flow groove disposed on the metering disk substrate and the metering disk. The turntable is fully embedded in the quantitative disk, and the quantitative disk substrate corresponds to the position and height of the turntable substrate. The quantitative disk cover plate corresponds to the position and height of the turntable cover plate. The flow channel and the selection channel switch between the sample storage state and the quantitative sampling state through the rotation of the turntable. The inlet (1) and the overflow (2) are located on the surface of the quantitative plate cover. The liquid storage channel (5) is connected to the outside through the inlet (1), and the waste liquid channel (6) is connected to the outside through the overflow (2). The interface one (3) and the interface two (4) are located on the surface of the quantitative plate cover. The sampling end of the quantitative channel (7) is connected to the outside through the interface one (3), and the quantitative channel (7) is connected to the sampling pump through the interface two (4).

5. The microfluidic chip for quantitative sampling according to claim 4, characterized in that: The volume of the quantitative channel (7) is 3μL-150μL, and the volume of the liquid storage channel (5) is greater than the volume of the quantitative channel (7).

6. The microfluidic chip for quantitative sampling according to claim 5, characterized in that: The port connection points of the flow channel on the quantitative plate and the port connection points of the selection channel on the turntable are both labyrinth seal structures (15).

7. The microfluidic chip for quantitative sampling according to claim 6, characterized in that: The edge of the turntable cover is provided with an auxiliary sample injection positioning groove (131) and an auxiliary sampling positioning groove (141). The sample injection positioning groove (13) and the sampling positioning groove (14) are set on the turntable substrate. The auxiliary sample injection positioning groove (131) is equal in size and corresponding in position to the sample injection positioning groove (13). The auxiliary sampling positioning groove (141) is equal in size and corresponding in position to the sampling positioning groove (14). The sample injection positioning groove (13) and the auxiliary sample injection positioning groove (131) form a hemispherical groove as a whole. The auxiliary sampling positioning groove (141) and the sampling positioning groove (14) form a hemispherical groove as a whole.

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