Micro-fluidic chip

Abstract

The utility model discloses a micro-fluidic chip, which relates to the field of containers or utensils for experiments, and a reaction unit of the micro-fluidic chip comprises a liquid inlet flow channel, a drainage groove, a reaction cavity, a closure groove and an exhaust flow channel which are communicated in sequence. The intercepting groove comprises a straight cylinder section and a transition section and serves as a capillary valve, and a liquid sample in the reaction cavity is inhibited from entering the exhaust flow channel before gas enters the exhaust flow channel. When the reaction cavity is gradually filled with the liquid sample, the gas is firstly squeezed into the exhaust flow channel, and the liquid sample converges into the intercepting groove only when the liquid sample spreads towards the intercepting groove, so that the situation that the gas in the reaction cavity cannot be exhausted is avoided. The drainage groove extends along the tangent line of the reaction cavity and is arranged on the side wall of the reaction cavity, so that the phenomenon that a liquid sample enters the reaction cavity and then directly flushes the exhaust flow channel to hinder gas exhaust can be avoided, and asymmetrical notches can be formed in the side wall of the reaction cavity, so that the interface energy at the front end of liquid flow is favorably damaged, and the reaction efficiency is improved. And a liquid sample can enter the reaction cavity more easily.

Description

Technical Field

[0001] The utility model relates to the field of containers or vessels for experiments, in particular to a microfluidic chip. Background Art

[0002] Microfluidic chip technology is called a laboratory on a chip, which can integrate all aspects of the experiment on a chip. Microfluidic chips have the advantages of high integration, small size, small reagent usage, low cost, and easy operation. Existing microfluidic chips have the following problems: Since the inlet of the exhaust flow channel is directly opened on the side wall of the reaction chamber, it is easy to be blocked by the liquid sample in the reaction chamber, resulting in part of the gas in the reaction chamber cannot be discharged in time, and it is easy to form bubbles in the reaction chamber, affecting the test results. Therefore, it is necessary to improve the flow channel structure of the microfluidic chip to prevent the blockage of the exhaust flow channel, so that the gas in the reaction chamber can be discharged in time and the formation of bubbles can be suppressed. Summary of the invention

[0003] The utility model aims to provide a microfluidic chip, which aims to overcome the problem in the prior art that the exhaust channel is easily blocked by liquid samples, resulting in difficulty in timely exhausting the gas in the reaction chamber.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] A microfluidic chip comprises a chip body provided with at least one reaction unit, wherein the reaction unit comprises a liquid inlet channel, a reaction chamber, a cut-off groove and an exhaust channel which are sequentially connected along a liquid flow direction; the cut-off groove comprises a straight section and a gradient section which are sequentially connected along the liquid flow direction; the straight section is connected to the side wall of the reaction chamber, the gradient section is connected to the exhaust channel, and the width of the gradient section gradually decreases along the liquid flow direction.

[0006] Furthermore, the depth ratio of the intercepting groove to the reaction chamber is 1:2-2:3.

[0007] Furthermore, the width and length of the straight tube section are both less than or equal to 1 mm.

[0008] Furthermore, the cross section of the gradient section is semicircular.

[0009] Furthermore, the liquid inlet channel is connected to the side wall of the reaction chamber through a drainage groove.

[0010] Furthermore, the drainage groove is extended along a tangent line of the reaction chamber and is arranged on a side wall of the reaction chamber.

[0011] In a specific embodiment, the drainage groove includes a first side wall and a second side wall, the first side wall and the second side wall are respectively on both sides of the tangent, and the first side wall and the reaction chamber are on the same side of the tangent; the second side wall is provided with an arc segment at one end close to the reaction chamber, and the concave surface of the arc segment faces the center of the reaction chamber.

[0012] Furthermore, the arc segment is smoothly connected to the side wall of the reaction chamber through a second round chamfer.

[0013] Furthermore, the depth of the drainage groove gradually increases from the liquid inlet channel to the reaction chamber.

[0014] Furthermore, the drainage groove and the intercepting groove are arranged opposite to each other on two sides of the reaction chamber.

[0015] In another specific embodiment, the drainage groove includes a first side wall and a second side wall, the first side wall and the reaction chamber are respectively on the same side of the tangent line, and the second side wall coincides with the tangent line.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] First, in the utility model, the intercepting groove includes a straight section and a gradient section. When the liquid sample wants to break through the notch and enter the straight section, a larger and more drastic change in the liquid surface contact angle is required, thereby inhibiting the liquid sample in the reaction chamber from entering the exhaust channel before the gas, acting as a capillary valve. When the reaction chamber is gradually filled with liquid, the gas is first squeezed into the exhaust channel, and the gradient section is conducive to the gathering and discharge of bubbles in the intercepting groove. As the liquid sample spreads toward the intercepting groove, the liquid sample will converge into the intercepting groove to prevent the gas in the reaction chamber from being unable to be discharged.

[0018] Secondly, in the present invention, the bottom of the intercepting groove is higher than the bottom of the reaction chamber, so that the side wall of the reaction chamber close to the bottom maintains a complete circumference, which is conducive to the liquid sample filling the bottom of the reaction chamber first, thereby making it easier for the gas to be discharged into the intercepting groove.

[0019] Third, in the present invention, the width and length of the straight section are both less than or equal to 1 mm, which is a small feature, has a good interception effect, and can better act as a capillary valve. The cross section of the gradient section is semicircular, which has a smooth transition feature compared to other shapes, is conducive to the gathering and discharge of bubbles, and prevents bubbles from adhering to corners.

[0020] Fourthly, in the utility model, the drainage groove is extended along the tangent line of the reaction chamber and arranged on the side wall of the reaction chamber, which can not only avoid the obstruction of gas discharge caused by the liquid sample directly rushing into the exhaust channel after entering the reaction chamber, but also form a notch on the side wall of the reaction chamber, and the notch is asymmetric, which helps to destroy the interfacial energy of the front end of the liquid flow, making it easier for the liquid sample to enter the reaction chamber.

[0021] Sixth, in the utility model, the first side wall and the second side wall of the drainage groove are respectively located on both sides of the tangent, and the second side wall is provided with an arc segment, which not only forms a gap with a larger width on the side wall of the reaction chamber, but also has an asymmetric property, making it easier for the liquid sample to enter the reaction chamber; the liquid flow can also be tangentially introduced into the bottom of the reaction chamber and then contact the freeze-dried balls, avoiding the obstruction of the discharge of bubbles due to the liquid sample directly rushing into the exhaust flow channel after entering the reaction chamber, which is conducive to the contact reaction between the liquid sample and the freeze-dried balls. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a front view of the chip body in the first embodiment of the present invention.

[0023] Figure 2 In the first embodiment of the present invention, the three-dimensional chip body Figure 1 .

[0024] Figure 3 In the utility model, the three-dimensional chip body Figure 2 .

[0025] Figure 4 for Figure 1 , a partial enlarged view of part A.

[0026] Figure 5 for Figure 2 A partial enlarged view of part A'.

[0027] Figure 6 for Figure 5 Schematic diagram from another perspective.

[0028] Figure 7 In the second embodiment of the present utility model, the partial enlargement of the unit Figure 1 .

[0029] Figure 8 In the second embodiment of the present utility model, the partial enlargement of the unit Figure 2 .

[0030] Fig. 9 In the second embodiment of the present utility model, the partial enlargement of the unit Figure 3 .

[0031] Fig.10 This is the front view of the chip body in the third embodiment of the present invention.

[0032] Fig.11 In the third embodiment of the present invention, the three-dimensional chip body Figure 1 .

[0033] Fig.12 In the third embodiment of the present invention, the three-dimensional chip body Figure 2 .

[0034] Fig.13 for Fig.11 , a partial enlarged view of part B. DETAILED DESCRIPTION

[0035] The specific implementation of the present invention is described below with reference to the accompanying drawings. In order to fully understand the present invention, many details are described below, but for those skilled in the art, the present invention can be implemented without these details.

[0036] Embodiment 1

[0037] like Figures 1 to 6 As shown, a microfluidic chip includes a chip body 1, and the chip body 1 is provided with sixteen reaction units 15. The number of reaction units 15 can be increased or decreased as needed, and is not limited to sixteen.

[0038] like Figures 1 to 6 As shown, the reaction unit 15 includes a liquid inlet channel 151, a drainage groove 152, a reaction chamber 153, a intercepting groove 154 and an exhaust channel 155 which are sequentially connected along the liquid flow direction, and a freeze-dried ball (not shown in the figure) is placed inside the reaction chamber 153.

[0039] like Figures 1 to 6 As shown, specifically, the intercepting groove 154 includes a straight section 154-1 and a gradient section 154-2 that are sequentially connected along the liquid flow direction, and the width of the gradient section 154-2 gradually decreases along the liquid flow direction. The intercepting groove 154 acts as a capillary valve to inhibit the liquid sample in the reaction chamber 153 from entering the exhaust channel 155 before the gas. When the reaction chamber 153 is gradually filled with the liquid sample, the gas is first squeezed into the exhaust channel 155. As the liquid sample spreads toward the intercepting groove, the liquid sample will converge into the intercepting groove 154, thereby effectively inhibiting the formation of bubbles inside the reaction chamber 153. In other words, it can effectively prevent the liquid from entering and blocking the exhaust channel 154 when the reaction chamber 153 is not fully filled, thereby causing the gas in the reaction chamber 153 to be unable to be discharged. In addition, while acting as a capillary valve, the intercepting groove 154 can also collect and accommodate bubbles in the reaction chamber 153, so that there are no dense bubbles in the circular groove of the reaction chamber 153.

[0040] like Figures 1 to 6 As shown, the bottom surface of the intercepting groove 154 is parallel to and higher than the bottom surface of the reaction chamber 153. Preferably, the depth ratio of the intercepting groove 154 to the reaction chamber 153 is 1:2-2:3. Preferably, the width D and length L of the straight section 154-1 are both less than or equal to 1 mm.

[0041] Preferably, the cross section of the gradual section 154-2 is semicircular. The semicircular shape has the characteristics of smooth transition, which is conducive to the gathering and discharge of bubbles and prevents bubbles from adhering to the corners. Of course, the cross section of the gradual section 154-2 can also be trapezoidal and limited to a semicircle.

[0042] like Figures 1 to 6 As shown, the drainage groove 152 is extended along the tangent line e of the reaction chamber 13 and is arranged on the side wall of the reaction chamber 13, which can avoid the gas discharge being hindered by the liquid sample directly rushing into the exhaust channel 155 after entering the reaction chamber. A gap with a larger width can be formed on the side wall of the reaction chamber 13, and the gap is asymmetric, which helps to destroy the interfacial energy of the front end of the liquid flow, making it easier for the liquid sample to enter the reaction chamber.

[0043] like Figures 1 to 6 As shown, specifically, the drainage groove 152 includes a first side wall 152a, a second side wall 152b and a bottom surface 152c. The drainage groove 152 is extended along the tangent line e of the reaction chamber 153 and is arranged on the side wall of the reaction chamber 153, and the first side wall 152a and the second side wall 152b are respectively located on both sides of the tangent line e, and the first side wall 152a and the reaction chamber 153 are located on the same side of the tangent line e. Preferably, the drainage groove 152 and the intercepting groove 154 are arranged on the side wall of the reaction chamber 153 opposite to each other. In other words, the extension direction of the drainage groove 152 is perpendicular to the tangent line e. If the extension direction of the drainage groove 152 is vertical, the tangent line e is horizontally extended.

[0044] like Figures 1 to 6 As shown, the first side wall 152a includes a first straight segment 152a-1 and a first round chamfer 152a-2, one end of the first straight segment 152a-1 is connected to the liquid inlet channel 151, and the other end is smoothly connected to the side wall of the reaction chamber 153 through the first round chamfer 152a-2. The second side wall 152b includes a second straight segment 152b-1, an arc segment 152b-2 and a second round chamfer 152b-3. Among them, one end of the second straight segment 152b-1 is connected to the liquid inlet channel 151, and the other end is tangent to the arc segment 152b-2; the concave surface of the arc segment 152b-2 faces the center of the reaction chamber 153, and the other end of the arc segment 152b-2 is smoothly connected to the side wall of the reaction chamber 153 through the second round chamfer 152b-3.

[0045] like Figures 1 to 6 As shown, the arc segment 152b-2 can guide the liquid flow smoothly, directing the liquid flow to the bottom of the freeze-dried ball 4 and contacting it, so that the freeze-dried ball 4 starts to dissolve in an orderly manner from the bottom closer to the drainage groove 152. In addition, the freeze-dried ball 4 itself has strong water absorption, which helps to accelerate the entry of the liquid sample. Of course, the arc segment 152b-2 can also be replaced by an inclined straight line segment, the purpose of which is to direct the liquid flow to the bottom of the freeze-dried ball 4.

[0046] like Figures 1 to 6 As shown, preferably, the groove depth of the drainage groove 152 gradually increases along the liquid flow direction, that is, gradually increases from the liquid inlet channel 151 to the reaction chamber 153. The increase in the groove depth of the drainage groove 152 helps to destroy the interfacial energy at the front end of the liquid flow. Specifically, the bottom surface 152c is a slope surface, so that the groove depth gradually increases. Preferably, the groove depth of the drainage groove 152 increases three times along the liquid flow direction.

[0047] like Figures 1 to 6 As shown, in addition, each reaction unit 15 is arranged in a ring-shaped distribution on the vertical surface of the chip body 1, and a sample adding chamber 11 is vertically arranged at the upper end of the chip body 1. The sample adding chamber 11 is connected to the liquid inlet channel 151 of each reaction unit 15 through a bifurcated flow channel. Since the sample adding chamber 11 is connected to the reaction unit 15 through the bifurcated flow channel, it is a conventional technology, and its specific structure is not repeated here.

[0048] It should be noted that, although the chip body 1 shown in the drawings of the specification of the present invention is a vertical microfluidic chip, the reaction unit 15 disclosed therein can also be applied to a horizontal microfluidic chip.

[0049] Embodiment 2

[0050] like Figures 1 to 9 As shown, the difference between the second embodiment and the first embodiment is that all the reaction units 15 arranged on the chip body 1 are specifically: the first side wall 152a and the reaction chamber 153 are located on the same side of the tangent line e, and the second side wall 152b coincides with the tangent line e. In addition, the first side wall 152a and the second side wall 152b are both planes.

[0051] Embodiment 3

[0052] like Figures 1 to 6 ,as well as Figures 10 to 13 As shown, the difference between the third embodiment and the second embodiment is that all the reaction units 15 provided on the chip body 1 are specifically: (1) the reaction units 15 are arranged in a matrix on the front of the chip body 1. (2) the drainage groove 152 extends vertically to the bottom side wall of the reaction chamber 153.

[0053] The above is only a specific implementation method of the utility model, but the design concept of the utility model is not limited to this. Any non-substantial changes to the utility model using this concept shall be deemed as an infringement of the protection scope of the utility model.

Claims

1. A microfluidic chip, comprising a chip body (1) provided with at least one reaction unit (15), wherein the reaction unit (15) comprises a liquid inlet channel (151), a reaction chamber (153), a cut-off groove (154) and an exhaust channel (155) which are sequentially connected along a liquid flow direction; characterized in that: The intercepting groove (154) comprises a straight section (154-1) and a gradual section (154-2) which are connected in sequence along the liquid flow direction; the straight section (154-1) is connected to the side wall of the reaction chamber (153), the gradual section (154-2) is connected to the exhaust flow channel (155), and the width of the gradual section (154-2) gradually decreases along the liquid flow direction.

2. A microfluidic chip according to claim 1, characterized in that: The depth ratio of the intercepting groove (154) to the reaction chamber (153) is 1:2-2:

3.

3. A microfluidic chip according to claim 1 or 2, characterized in that: The bottom surface of the intercepting groove (154) is parallel to and higher than the bottom surface of the reaction chamber (153).

4. A microfluidic chip according to claim 1 or 2, characterized in that: The width (D) and length (L) of the straight tube section (154-1) are both less than or equal to 1 mm.

5. A microfluidic chip according to claim 1 or 2, characterized in that: The cross section of the gradient section (154-2) is semicircular.

6. A microfluidic chip according to claim 1, characterized in that: The liquid inlet channel (151) is connected to the side wall of the reaction chamber (153) through the drainage groove (152).

7. A microfluidic chip according to claim 6, characterized in that: The drainage groove (152) is extended along a tangent line (e) of the reaction chamber (153) and is arranged on a side wall of the reaction chamber (153).

8. A microfluidic chip according to claim 7, characterized in that: The drainage groove (152) comprises a first side wall (152a) and a second side wall (152b), the first side wall (152a) and the second side wall (152b) are respectively located on both sides of the tangent (e), and the first side wall (152a) and the reaction chamber (153) are located on the same side of the tangent (e); an arc segment (152b-2) is provided at one end of the second side wall (152b) close to the reaction chamber (153), and the concave surface of the arc segment (152b-2) faces the center of the reaction chamber (153).

9. A microfluidic chip according to claim 7 or 8, characterized in that: The depth of the drainage groove (152) gradually increases from the liquid inlet channel (151) to the reaction chamber (153).

10. A microfluidic chip according to claim 6, 7 or 8, characterized in that: The drainage groove (152) and the intercepting groove (154) are arranged opposite to each other on two sides of the reaction chamber (153).

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