Micro-fluidic chip capable of realizing liquid quantification
By designing quantitative inlet channels, waste liquid channels, and quantitative outlet channels in a microfluidic chip, and combining them with a hydrophobic and breathable membrane, the complexity and high cost of quantitative detection in POCT scenarios using microfluidic chips are solved, enabling simple liquid sample quantification and transfer.
Patent Information
- Application Number
- CN202520093256.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-15
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2035-01-15
AI Technical Summary
Existing microfluidic chips require professional technicians to operate in quantitative detection and are difficult to integrate with downstream detection processes. Especially in POCT scenarios where portability and low cost are required, traditional centrifugal-driven and valve-structured designs are complex and difficult to apply.
A simple microfluidic chip is designed. By setting quantitative inlet channels, waste liquid channels and quantitative outlet channels on the main body layer and the cover plate layer, quantitative liquid is achieved by utilizing the difference in channel diameter and positive pressure driving force. Combined with hydrophobic and breathable membrane to control flow, it avoids complex valve structures and high-cost equipment.
It enables simple quantification and transfer of liquid samples, reduces the professional requirements of operators, is suitable for POCT scenarios, simplifies the operation process, and reduces equipment costs.
Smart Images
Figure CN223732799U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to micro -fluidic chip technical field more specifically relates to a kind of micro -fluidic chip of realizing liquid ration. BACKGROUND
[0002] In Vitro Diagnosis (IVD) refers to the detection of specific indicators in human urine, blood and other body fluid samples outside the human body with the help of some instruments and equipment, and then determine and judge the disease state. Clinically, most diseases require quantitative detection of test results for accurate diagnosis, which requires quantitative transfer of collected samples during sample pretreatment. In large hospitals and third-party testing laboratories, this step usually requires professional technicians to manually operate, and the entire detection process usually uses a large-scale analyzer pipeline mode, which is bulky, low in integration, time-consuming and limits its application in emergency rapid detection, community clinics and many other point-of-care testing (POCT) application scenarios.
[0003] Microfluidic technology has the ability to integrate sample collection, pretreatment, mixing reaction, detection and other operation units on a centimeter-sized chip, with the advantages of small size, easy integration, miniaturization and automation. The application of microfluidic chips in IVD detection can greatly reduce the demand for professional operation personnel, especially in the POCT field.
[0004] However, sample quantification is a prerequisite for quantitative detection results. Currently, the operation of quantitatively sampling collected samples in clinical practice requires professional technicians to use professional tools or instruments, which is time-consuming and labor-intensive on the one hand, and difficult to integrate with downstream detection processes on the other hand to meet the POCT application requirements.
[0005] In addition, the core of the detection process realized on the microfluidic chip is the driving control of the fluid. At present, in the quantitative detection application, it is mainly divided into pressure driving type and centrifugal force driving type. The liquid sample in the centrifugal microfluidic chip can move along the circumference under the action of centrifugal force, and different volumes of quantitative distribution can be realized by designing different volumes of liquid pool at the circumferential position, without complex valve structure design. Although the centrifugal force driving type microfluidic chip has the advantage of easy realization of quantitative distribution, the detection methodology for multi-step reaction is not as flexible as the pressure driving type, and the centrifugal chip needs to be matched with a special centrifuge to complete the fluid driving, and the system cost and complexity are relatively high. By driving the sample to the liquid pool by pressure, the related field technicians can easily analogize to the structure of opening the gate to release water. After the reservoir is full, the upper and lower gates need to be closed, that is, the valve in the microfluidic chip, in order to realize the quantitative function. However, this structure valve design is more, and the control requirement of the peripheral instrument is also higher, which is difficult to be actually applied to the POCT scene with strong requirements of portability and low cost, especially the home version of POCT.
[0006] Therefore, it is an urgent problem for those skilled in the art to provide a simple structure and a valve-free quantitative microfluidic chip. Practical new type content
[0007] Therefore, the utility model provides a microfluidic chip can realize liquid quantitative, aims at solving above -mentioned technical problem.
[0008] In order to realize the above-mentioned purpose, the utility model adopts the following technical scheme:
[0009] A microfluidic chip can realize liquid quantitative, including main body layer, and the cover plate layer sealedly attached on the surface of main body layer;
[0010] The surface of main body layer is provided with quantitative pool, quantitative inlet channel, waste liquid channel and quantitative outlet channel, the inlet end of quantitative pool is communicated with quantitative inlet channel and waste liquid channel, the outlet end of quantitative pool on the other side is communicated with quantitative outlet channel, the caliber of quantitative inlet channel is greater than the caliber of waste liquid channel, and the caliber of waste liquid channel is greater than the caliber of quantitative outlet channel;
[0011] The first gas hole is communicated through the surface of cover plate layer, the first gas hole corresponds to one end of waste liquid channel away from quantitative pool, and the surface of cover plate layer is sealedly attached with hydrophobic gas permeable membrane covering first gas hole.
[0012] By the technical scheme, the micro-fluidic chip provided by the utility model overcomes the defects of traditional centrifugal driving mode and complex valve structure, the quantitative pool has a predetermined volume, a positive pressure driving force is provided to the quantitative inlet channel, sample solution flows into the quantitative pool, because the caliber of the waste liquid channel is larger than that of the quantitative outlet channel, the solution will preferentially flow into the waste liquid channel after filling the quantitative pool, until the hydrophobic air-permeable membrane at the first air hole corresponding to the waste liquid channel is blocked, after the excess liquid is transferred to the waste liquid channel, the quantitative liquid of the quantitative pool then flows out through the quantitative outlet channel, realizing the quantification and transfer of liquid sample. The micro-fluidic chip provided by the utility model has simple structure, only needs to provide a positive pressure driving force to the quantitative inlet channel, can realize the quantification and transfer of solution by the caliber difference of the quantitative inlet channel, the waste liquid channel and the quantitative outlet channel, is simple to operate, is convenient to integrate and meets the needs of different POCT application scenarios.
[0013] It should be noted that the quantitative inlet channel, the waste liquid channel and the quantitative outlet channel provided by the utility model are in communication with the quantitative pool, but need to be driven by the equipment to make the liquid flow, because:
[0014] 1. The hindering effect of surface tension: Under the microscale in the micro-fluidic chip, the surface tension of the liquid becomes very significant. The surface tension will form a "film" on the surface of the liquid, making it difficult for the liquid to flow spontaneously. For example, a water droplet will maintain a spherical shape without external force, and will not spontaneously spread or flow.
[0015] 2. The limitation of capillary effect: In the micro-channel of the micro-fluidic chip, the interaction between the liquid and the channel wall will produce capillary effect. When the size of the channel is very small (such as microns), the capillary effect will cause the liquid to form a stable liquid column in the channel, and a large capillary pressure needs to be overcome to make the liquid flow.
[0016] 3. Increase of viscous resistance: The channel in the micro-fluidic chip is usually very narrow, which makes the viscous resistance of the fluid during flow significantly increase. The viscous resistance is caused by the friction within the fluid and the friction between the fluid and the channel wall. In the microscale, the viscous force of the fluid is larger than the inertial force, so the flow of the fluid is more hindered.
[0017] 4. Comparison of inertial force and viscous force: In the microscale, the inertial force of the fluid is very small compared to the viscous force. The inertial force is one of the driving forces of fluid flow, which is related to the velocity and mass of the fluid. In the micro-fluidic chip, because the volume and velocity of the fluid are very small, the inertial force is not enough to overcome the viscous resistance and surface tension and other hindering factors.
[0018] Therefore, it is difficult for the liquid in the microfluidic chip to flow without external driving force, mainly due to the combined action of multiple factors such as surface tension, fluid resistance and weakening of fluid inertia, and the special design requirements of the chip.
[0019] Therefore, in the utility model, the influence principle of the diameter difference of the quantitative inlet channel, the waste liquid channel and the quantitative outlet channel on the liquid flow resistance is mainly explained by Poiseuille's Law in fluid mechanics.
[0020] Poiseuille's Law describes that under laminar flow conditions, the flow rate of fluid through a cylindrical pipe is proportional to the fourth power of the pipe radius, and inversely proportional to the pipe length and the viscosity of the fluid. Specifically, the flow rate Q can be expressed as:
[0021]
[0022] Wherein:
[0023] ΔP is the pressure difference between the two ends of the pipe,
[0024] r is the radius of the pipe,
[0025] η is the viscosity of the fluid,
[0026] L is the length of the pipe.
[0027] From this formula, it can be seen that the diameter (radius) of the channel has a significant effect on the flow rate of the fluid. The larger the diameter, the larger the flow rate, that is, the fluid is more likely to flow through the channel with a larger diameter. This is because the channel with a larger diameter provides a larger cross-sectional area, thereby reducing the resistance of the fluid flow. Therefore, in the microfluidic chip, when the air pressure is applied, the solution will preferentially select the channel with a larger diameter to flow, because the resistance of these channels is smaller and the fluid is more likely to pass through. The utility model takes into account the above factors when designing the microfluidic chip to ensure that the fluid flows along the expected path.
[0028] Preferably, in the above-mentioned microfluidic chip capable of realizing liquid quantification, a sample pool is opened on the surface of the main body layer, the sample pool is in communication with one end of the quantitative inlet channel away from the quantitative pool, a through sample inlet is opened on the cover plate layer, and the sample inlet corresponds to the sample pool.
[0029] Preferably, in the above-mentioned microfluidic chip capable of realizing liquid quantification, the volume of the sample pool is greater than the volume of the quantitative pool, and is less than the volume sum of the quantitative pool and the waste liquid channel.
[0030] Preferably, in the above-mentioned microfluidic chip capable of realizing liquid quantification, the sample inlet is used for injecting sample liquid and is connected to a positive pressure pump.
[0031] Preferably, in the microfluidic chip that enables quantitative liquid flow, the positive pressure pump has a flow rate range of 10 μL / min to 1000 μL / min.
[0032] Preferably, in the microfluidic chip that enables quantitative liquid dispensing described above, a transfer pool is formed on the surface of the main body layer, the transfer pool is connected to the end of the quantitative outlet channel away from the quantitative pool, and a through second vent is formed on the cover plate layer, the second vent corresponding to the transfer pool.
[0033] Preferably, in the microfluidic chip that enables quantitative liquid distribution, the quantitative inlet channel, the waste liquid channel, and the quantitative outlet channel have the same depth and a width ratio of 4:2:1.
[0034] As can be seen from the above technical solution, compared with the prior art, this utility model discloses a microfluidic chip that can realize quantitative liquid distribution, which has the following beneficial effects:
[0035] 1. The chip structure of this utility model is simple and easy to operate. It can integrate pre-processing steps and back-end reaction functions to achieve quantitative detection, which meets the needs of POCT application scenarios.
[0036] 2. This utility model only needs to provide positive pressure driving force to the quantitative inlet channel to realize the quantitative transfer of solution by utilizing the difference in diameter between the quantitative inlet channel, the waste liquid channel and the quantitative outlet channel.
[0037] 3. The liquid drive in the chip of this utility model has low requirements for supporting equipment. It can be driven by a simple pump device and does not require expensive and limited centrifugal drive equipment. Attached Figure Description
[0038] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0039] Figure 1 The attached figure is a schematic diagram of the structure of the microfluidic chip that enables quantitative liquid measurement provided by this utility model;
[0040] Figure 2 The attached figure is an exploded view of the structure of the microfluidic chip that enables quantitative liquid measurement provided by this utility model;
[0041] Figure 3 The attached figure is a schematic diagram of the surface structure of the main body layer provided by this utility model.
[0042] wherein:
[0043] 1 - body layer;
[0044] 11 - dosing pool; 12 - dosing inlet channel; 13 - waste channel; 14 - dosing outlet channel; 15 - sample pool; 16 - transfer pool;
[0045] 2 - cover layer;
[0046] 21 - first air hole; 22 - sample inlet; 23 - second air hole;
[0047] 3 - hydrophobic gas permeable membrane. DETAILED DESCRIPTION
[0048] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0049] Referring to the drawings Figure 1 to the drawings Figure 3 The embodiment of the present application discloses a microfluidic chip capable of realizing liquid dosing, comprising a body layer 1 and a cover layer 2 sealed and attached to the surface of the body layer 1.
[0050] The surface of the body layer 1 is provided with a dosing pool 11, a dosing inlet channel 12, a waste channel 13 and a dosing outlet channel 14. The dosing inlet channel 12 and the waste channel 13 are in communication with the inlet end of the dosing pool 11, the dosing outlet channel 14 is in communication with the outlet end of the dosing pool 11 on the other side, and the caliber of the dosing inlet channel 12 is greater than that of the waste channel 13, which is greater than that of the dosing outlet channel 14.
[0051] The cover layer 2 is provided with a through first air hole 21 corresponding to the end of the waste channel 13 away from the dosing pool 11, and the surface of the cover layer 2 is sealed and attached with a hydrophobic gas permeable membrane 3 covering the first air hole 21.
[0052] In order to further optimize the above technical solution, the surface of the body layer 1 is provided with a sample pool 15, the sample pool 15 is in communication with the end of the dosing inlet channel 12 away from the dosing pool 11, and the cover layer 2 is provided with a through sample inlet 22 corresponding to the sample pool 15.
[0053] In order to further optimize the above technical solution, the volume of the sample pool 15 is greater than the volume of the dosing pool 11, and less than the volume sum of the dosing pool 11 and the waste channel 13.
[0054] To further optimize the above technical solutions, the sample inlet 22 is used to inject the sample liquid and is connected to the positive pressure pump.
[0055] To further optimize the above technical solutions, the flow rate range of the positive pressure pump is 10 μL / min-1000 μL / min.
[0056] To further optimize the above technical solutions, the main body layer 1 is provided with a transfer pool 16, the transfer pool 16 is in communication with one end of the quantitative outlet channel 14 away from the quantitative pool 11, the cover plate layer 2 is provided with a second air hole 23, and the second air hole 23 corresponds to the transfer pool 16.
[0057] In the embodiment, the quantitative inlet channel 12, the waste liquid channel 13 and the quantitative outlet channel 14 have the same depth, and the width ratio is 4:2:1.
[0058] In the embodiment, the quantitative pool 11 has a predetermined volume, under the action of an external driving force, liquid flows into the quantitative pool 11 from the quantitative inlet channel 12, after filling the quantitative pool 11, the excess liquid enters the waste liquid channel 13, until the hydrophobic air-permeable membrane 3 at the first air hole 21 corresponding to the waste liquid channel 13 is blocked, and the quantitative liquid in the quantitative pool 11 then enters the transfer pool 16 through the quantitative outlet channel 14, realizing the quantification and transfer of the liquid sample.
[0059] The liquid quantification structure provided in the embodiment realizes the quantification of the sample through a liquid quantification pool with a specific size, has a simple structure, high quantification accuracy, can use equipment or equipment-free driven liquid according to actual application requirements, is easy to operate, is convenient for integration, and meets the needs of different POCT application scenarios.
[0060] The quantification structure provided in the embodiment has serum separation and quantification capability, after the sample pool 15 is provided with a blood filter membrane, whole blood samples are directly added to the blood filter membrane of the sample pool 15, serum separation is realized under the driving force, and the quantification and transfer of the serum are completed, without the need for manual serum extraction steps, greatly simplifying the operation.
[0061] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts of each embodiment can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the related parts can be referred to the method part.
[0062] The above description of disclosed embodiments enables one of ordinary skill in the art to make or use the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A microfluidic chip capable of realizing liquid quantification, comprising a main body layer (1) and a cover layer (2) sealed and attached to the surface of the main body layer (1); characterized in that: the surface of the main body layer (1) is provided with a quantification pool (11), a quantification inlet channel (12), a waste liquid channel (13) and a quantification outlet channel (14), the quantification inlet channel (12) and the waste liquid channel (13) are in communication with the inlet end of the quantification pool (11), the quantification outlet channel (14) is in communication with the outlet end of the other side of the quantification pool (11), the diameter of the quantification inlet channel (12) is greater than that of the waste liquid channel (13), and the diameter of the waste liquid channel (13) is greater than that of the quantification outlet channel (14); the cover layer (2) is provided with a first air hole (21) penetrating therethrough, the first air hole (21) corresponds to the end of the waste liquid channel (13) away from the quantification pool (11), and the surface of the cover layer (2) is sealed and attached with a hydrophobic air-permeable membrane (3) covering the first air hole (21).
2. The microfluidic chip capable of realizing liquid quantification according to claim 1, wherein, the surface of the main body layer (1) is provided with a sample pool (15), the sample pool (15) is in communication with the end of the quantification inlet channel (12) away from the quantification pool (11), and the cover layer (2) is provided with a sample inlet (22) penetrating therethrough, the sample inlet (22) corresponds to the sample pool (15).
3. The microfluidic chip capable of realizing liquid quantification according to claim 2, characterized in that, The volume of the sample pool (15) is greater than that of the quantification pool (11) and less than the sum of the volumes of the quantification pool (11) and the waste liquid channel (13).
4. The microfluidic chip capable of realizing liquid quantification according to claim 2, characterized in that, The sample inlet (22) is used for injecting sample liquid and is connected to a positive pressure pump.
5. The microfluidic chip capable of realizing liquid quantification according to claim 4, characterized in that, The flow rate of the positive pressure pump ranges from 10 μL / min to 1000 μL / min.
6. The microfluidic chip capable of realizing liquid quantification according to claim 1, wherein, the surface of the main body layer (1) is provided with a transfer pool (16), the transfer pool (16) is in communication with the end of the quantification outlet channel (14) away from the quantification pool (11), and the cover layer (2) is provided with a second air hole (23) penetrating therethrough, the second air hole (23) corresponds to the transfer pool (16).
7. The microfluidic chip capable of realizing liquid quantification according to claim 1, wherein, The depths of the quantification inlet channel (12), the waste liquid channel (13) and the quantification outlet channel (14) are the same, and the width ratio is 4:2:1.