Temperature control device and droplet type digital PCR instrument

Abstract

The invention discloses a temperature control device and a droplet type digital PCR instrument, and relates to the technical field of nucleic acid detection. The temperature control device comprises a base, a temperature control mechanism, a heat conducting plate, a reaction disc and a vacuumizing mechanism. The temperature control mechanism is installed on the base and connected with the heat conduction plate, the reaction disc is placed on the heat conduction plate and comprises a disc body and a flexible film, the flexible film is connected to the bottom of the disc body and used for bearing liquid drops to be detected, the heat conduction plate is provided with an air exhaust hole, and the vacuumizing mechanism is communicated with the air exhaust hole. The vacuumizing mechanism is used for pumping out air between the flexible film and the heat conduction plate so that the flexible film can be tightly attached to the heat conduction plate. Compared with the prior art, the temperature control device provided by the invention adopts the flexible film connected to the bottom of the disc body and the vacuumizing mechanism communicated with the air exhaust hole, so that the thermal resistance and the thermal capacity can be effectively reduced under the condition that the flatness of a liquid drop contact surface is ensured, the heating and cooling rates are improved, the uniform temperature distribution is ensured, and the material cost is reduced; the economic benefit is improved.

Description

Technical Field

[0001] The present invention relates to the field of nucleic acid detection technology, and in particular to a temperature control device and a droplet digital PCR instrument. Background Art

[0002] Droplet digital PCR is an absolute quantitative PCR technology that mainly uses a droplet method to disperse a solution containing the target nucleic acid into a large number of oil-in-water droplets to form tens of thousands of independent micro-reaction systems of equal volume. The initial number of target nucleic acid templates in each droplet is 0, 1 or more. In this way, after the PCR cycle, the droplet with an initial target nucleic acid will give a fluorescent signal, and the droplet without the target nucleic acid will not have a fluorescent signal. The target nucleic acid concentration of the original solution can be inferred based on the relative proportion of the two droplet numbers and the mathematical correction of the Poisson distribution.

[0003] Droplet digital PCR requires thermal cycling (using a temperature control device to perform temperature rise and fall cycles on the droplets), which requires the droplet contact surface to be flat and horizontal to ensure that the droplets are closely arranged in the reaction pool without flowing due to gravity. In order to meet the demand for a flat droplet contact surface, current droplet digital PCR instruments use hard materials such as aluminum plates or glass plates with a certain thickness (0.5mm-1mm) as droplet contact surface materials. However, in this way, first, the thicker contact surface has a larger thermal resistance and heat capacity, which is not conducive to increasing the heating and cooling rate; second, the droplet contact surface and the thermal conductive surface of the temperature control device are both solid materials with high rigidity. Even if the processing accuracy is high, uneven contact is inevitable, resulting in uneven temperature distribution at various positions; third, in order to prevent cross-contamination, the droplet contact surface is a disposable consumable, and the material cost of glass plates or aluminum plates is relatively high.

[0004] In view of this, it is particularly important to design and manufacture a temperature control device and a droplet digital PCR instrument with high heating and cooling rates, uniform temperature distribution, and low material cost, especially in nucleic acid detection. Summary of the invention

[0005] The object of the present invention is to provide a temperature control device that can effectively reduce thermal resistance and heat capacity while ensuring the flatness of the droplet contact surface, increase the heating and cooling rate, ensure uniform temperature distribution, reduce material costs, and improve economic benefits.

[0006] Another object of the present invention is to provide a droplet digital PCR instrument that can effectively reduce thermal resistance and heat capacity while ensuring the flatness of the droplet contact surface, increase the heating and cooling rates, ensure uniform temperature distribution, reduce material costs, and improve economic benefits.

[0007] The present invention is achieved by adopting the following technical solutions.

[0008] A temperature control device comprises a base, a temperature control mechanism, a heat conduction plate, a reaction disk and a vacuum mechanism. The temperature control mechanism is installed on the base and connected to the heat conduction plate. The reaction disk is placed on the heat conduction plate. The reaction disk comprises a disk body and a flexible membrane. The flexible membrane is connected to the bottom of the disk body. The flexible membrane is used to carry droplets to be tested. The heat conduction plate is provided with an air extraction hole. The vacuum mechanism is connected to the air extraction hole. The vacuum mechanism is used to extract air between the flexible membrane and the heat conduction plate so that the flexible membrane and the heat conduction plate are tightly fitted.

[0009] Optionally, the reaction disk further comprises a flexible partition wall, the flexible partition wall is connected to the flexible membrane, the flexible partition wall and the flexible membrane together form at least one containing groove, and the containing groove is used to contain the droplets to be tested.

[0010] Optionally, the heat conducting plate is provided with an exhaust groove, and the exhaust hole is arranged on the bottom wall of the exhaust groove.

[0011] Optionally, the position of the flexible partition wall corresponds to the position of the exhaust slot.

[0012] Optionally, the heat conducting plate is provided with a sealing groove, a sealing ring is arranged in the sealing groove, and the sealing ring abuts against the disk body.

[0013] Optionally, the temperature control mechanism includes a heating and cooling element, a temperature sensor and a radiator. The temperature sensor is connected to the heat conducting plate. The temperature sensor is used to detect the real-time temperature of the heat conducting plate. The heating and cooling element and the radiator are both installed on the base and connected to the heat conducting plate. The heating and cooling element is used to heat or cool the heat conducting plate, and the radiator is used to cool the heat conducting plate.

[0014] Optionally, the vacuum extraction mechanism includes a vacuum pump, a tee and an air pressure sensor, the first end of the tee is connected to the air extraction hole, the second end of the tee is connected to the vacuum pump, and the third end of the tee is connected to the air pressure sensor. The vacuum pump is used to extract air outwards, and the air pressure sensor is used to detect the real-time vacuum degree.

[0015] Optionally, the temperature control device also includes a positioning mechanism, which includes a positioning frame and a positioning member. The positioning frame is installed on the base and is also surrounded by the heat conduction plate and the outside of the disk body. The disk body is provided with a limiting groove. The positioning member can be movably installed on the positioning frame and cooperate with the limiting groove.

[0016] Optionally, the positioning member includes an elastic member and a round ball, the positioning frame is provided with a positioning groove, one end of the elastic member is connected to the bottom wall of the positioning groove, and the other end is connected to the round ball, and the round ball is slidably arranged in the positioning groove; the limiting groove is arranged in a conical shape, the midpoint of the limiting groove is higher than the center of the round ball, the round ball extends into the limiting groove and abuts against the side wall of the limiting groove.

[0017] A droplet digital PCR instrument comprises the above-mentioned temperature control device, which comprises a base, a temperature control mechanism, a heat conduction plate, a reaction disk and a vacuum mechanism. The temperature control mechanism is installed on the base and connected to the heat conduction plate. The reaction disk is placed on the heat conduction plate. The reaction disk comprises a disk body and a flexible membrane. The flexible membrane is connected to the bottom of the disk body. The flexible membrane is used to carry droplets to be tested. The heat conduction plate is provided with an air extraction hole. The vacuum mechanism is connected to the air extraction hole. The vacuum mechanism is used to extract air between the flexible membrane and the heat conduction plate so that the flexible membrane and the heat conduction plate fit tightly.

[0018] The temperature control device and droplet digital PCR instrument provided by the present invention have the following beneficial effects:

[0019] The temperature control device provided by the present invention has a temperature control mechanism installed on a base and connected to a heat conducting plate, a reaction plate is placed on the heat conducting plate, the reaction plate includes a plate body and a flexible membrane, the flexible membrane is connected to the bottom of the plate body, the flexible membrane is used to carry the droplets to be tested, the heat conducting plate is provided with an air extraction hole, a vacuum extraction mechanism is connected to the air extraction hole, and the vacuum extraction mechanism is used to extract the air between the flexible membrane and the heat conducting plate so that the flexible membrane and the heat conducting plate are closely fitted. Compared with the prior art, the temperature control device provided by the present invention uses a flexible membrane connected to the bottom of the plate body and a vacuum extraction mechanism connected to the air extraction hole, so it can effectively reduce thermal resistance and heat capacity while ensuring the flatness of the droplet contact surface, increase the heating and cooling rate, ensure uniform temperature distribution, reduce material costs, and improve economic benefits.

[0020] The droplet digital PCR instrument provided by the present invention includes a temperature control device, which can effectively reduce thermal resistance and heat capacity while ensuring the flatness of the droplet contact surface, increase the heating and cooling rate, ensure uniform temperature distribution, reduce material costs, and improve economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 A schematic diagram of the structure of a temperature control device provided in an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of the structure of the connection between the temperature control mechanism and the base in the temperature control device provided in an embodiment of the present invention;

[0024] Figure 3 An exploded view of the connection between the temperature control mechanism and the base in the temperature control device provided by an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of the structure of a vacuum pumping mechanism in a temperature control device provided in an embodiment of the present invention;

[0026] Figure 5 An exploded view of a reaction disk in a temperature control device provided by an embodiment of the present invention;

[0027] Figure 6 A schematic diagram of the structure of a reaction disk in a temperature control device provided in an embodiment of the present invention;

[0028] Figure 7 A schematic diagram of the structure of a heat conducting plate in a temperature control device provided in an embodiment of the present invention;

[0029] Figure 8 A partial cross-sectional view of a heat conducting plate in a temperature control device provided by an embodiment of the present invention;

[0030] Fig. 9 An exploded view of the cooperation between the reaction disk and the positioning mechanism in the temperature control device provided by the embodiment of the present invention;

[0031] Fig.10 A cross-sectional view of the cooperation between the reaction disk and the positioning mechanism in the temperature control device provided by an embodiment of the present invention.

[0032] Icons: 100-temperature control device; 110-base; 120-temperature control mechanism; 121-heating and cooling element; 122-temperature sensor; 123-heat sink; 130-heat conducting plate; 131-exhaust hole; 1311-extension section; 1312-exhaust section; 132-exhaust groove; 1321-horizontal groove; 1322-vertical groove; 133-heat transfer area; 134-sealing groove; 140-reaction disk; 141-disk body ; 1411-limiting groove; 142-flexible membrane; 143-flexible partition wall; 1431-horizontal bar; 1432-vertical bar; 144-accommodating groove; 150-vacuum extraction mechanism; 151-vacuum pump; 152-tee pipe; 153-air pressure sensor; 160-sealing ring; 170-positioning mechanism; 171-positioning frame; 1711-positioning groove; 172-positioning piece; 1721-elastic piece; 1722-round ball. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the present invention, it should be noted that the terms "inside", "outside", "upper", "lower", "horizontal", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the invention is usually placed when in use, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0037] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments can be combined with each other.

[0039] Please refer to Figures 1 to 8 The embodiment of the present invention provides a droplet digital PCR instrument (not shown) for nucleic acid detection. It can effectively reduce thermal resistance and heat capacity while ensuring the flatness of the droplet contact surface, increase the heating and cooling rate, ensure uniform temperature distribution, reduce material costs, and improve economic benefits.

[0040] The micro-droplet digital PCR instrument includes a micro-droplet generating device (not shown), a temperature control device 100 and a microscopic photographing device (not shown). The micro-droplet generating device is used to make a large number of water-in-oil droplets (test droplets) from the original solution in a sample, and inject these test droplets into the temperature control device 100; the temperature control device 100 is used to perform a temperature rise and fall cycle on these test droplets, and each time a temperature rise and fall cycle is performed, the number of target nucleic acids in each test droplet doubles, and this is repeated to greatly increase the number of trace target nucleic acids; the microscopic photographing device is used to photograph and measure all the test droplets after the temperature rise and fall cycle is completed. The test droplets with target nucleic acids initially will give a fluorescent signal, and the test droplets without target nucleic acids will not have a fluorescent signal. According to the relative proportion of the number of the two test droplets and the mathematical correction of the Poisson distribution, the target nucleic acid concentration of the original solution in the corresponding sample can be calculated.

[0041] The temperature control device 100 includes a base 110, a temperature control mechanism 120, a heat conducting plate 130, a reaction disk 140 and a vacuum mechanism 150. The temperature control mechanism 120 is mounted on the base 110 and connected to the heat conducting plate 130. The reaction disk 140 is placed on the heat conducting plate 130. The heat conducting plate 130 has a good heat conducting effect. The reaction disk 140 is used to hold the droplets to be tested. The temperature control mechanism 120 is used to heat or cool the reaction disk 140 through the heat conducting plate 130 to achieve the temperature rise and fall function of the reaction disk 140, thereby performing a temperature rise and fall cycle on the droplets to be tested.

[0042] Further, the reaction disk 140 includes a disk body 141 and a flexible membrane 142. The bottom of the disk body 141 is hollowed out, and the flexible membrane 142 is connected to the bottom of the disk body 141. The flexible membrane 142 is used to carry the droplets to be tested, and the temperature control mechanism 120 is used to heat or cool the droplets to be tested through the flexible membrane 142. Specifically, when the reaction disk 140 is normally placed on the heat conducting plate 130, there will inevitably be a gap between the heat conducting plate 130 and the flexible membrane 142, so that the contact between the heat conducting plate 130 and the flexible membrane 142 is uneven, thereby causing the heat transfer from the heat conducting plate 130 to the flexible membrane 142 to be not fast and uniform enough. Therefore, the heat conducting plate 130 is provided with an exhaust hole 131 , and the vacuum mechanism 150 is connected to the exhaust hole 131 . The vacuum mechanism 150 is used to extract the air between the flexible membrane 142 and the heat conducting plate 130 so that the flexible membrane 142 and the heat conducting plate 130 fit tightly together and eliminate the gap between the heat conducting plate 130 and the flexible membrane 142 . In this way, on the one hand, the flexible film 142 can be laid flat on the heat conducting plate 130 to improve the flatness of the flexible film 142, thereby ensuring the flatness of the droplet contact surface. At this time, it is only necessary to control the heat conducting plate 130 to be in a horizontal state to ensure the horizontality of the droplet contact surface and ensure that the droplets to be tested are closely arranged without flowing due to gravity; on the other hand, the thermal resistance and thermal capacity can be effectively reduced (the thickness of the flexible film 142 is relatively thin, and its thermal resistance and thermal capacity are much smaller than those of the glass plate or the aluminum plate), and the heat transfer efficiency can be improved, thereby increasing the heating and cooling rate and ensuring uniform temperature distribution; on the other hand, the material cost can be reduced (the material cost of the flexible film 142 is much lower than that of the glass plate or the aluminum plate), thereby improving economic benefits.

[0043] Preferably, the disk 141 is made of a plastic material such as polypropylene, and the flexible film 142 is made of a material such as aluminum foil, aluminum-plastic film, polypropylene film or polyimide film, with a thickness of 0.025 mm-0.05 mm, which has a relatively thin thickness and good flexibility. The base 110 is made of aluminum material and serves as a structural support base for the entire temperature control device 100. The heat conducting plate 130 is made of common high thermal conductivity materials such as aluminum, copper or silver, which has a high thermal conductivity efficiency.

[0044] Specifically, the flexible film 142 is fixedly connected to the bottom of the disk body 141 by bonding or hot melting to ensure sealing and prevent leakage. Since the thickness of the flexible film 142 is 1-2 orders of magnitude thinner than the thickness of the glass plate or aluminum plate in the prior art, the thermal resistance and heat capacity can be greatly reduced, thereby achieving the purpose of increasing the heating and cooling rate. Since the rigidity of the flexible film 142 is relatively low, after the vacuum mechanism 150 extracts the air between the flexible film 142 and the heat conducting plate 130, the flexible film 142 will be tightly attached to the heat conducting plate 130 under the action of atmospheric pressure. Due to the uniformity of atmospheric pressure, the pressure on the contact surface between the flexible film 142 and the heat conducting plate 130 is equal, thereby improving the uniformity of thermal conductivity.

[0045] Preferably, the reaction disk 140 further includes a flexible partition wall 143. The flexible partition wall 143 is connected to the flexible membrane 142, and the flexible partition wall 143 is disposed on the upper surface of the flexible membrane 142. Since the flexible partition wall 143 is also flexible, it can deform along with the flexible membrane 142 to avoid affecting the tight fit between the flexible membrane 142 and the heat conducting plate 130. Specifically, the flexible partition wall 143 and the flexible membrane 142 together form at least one receiving groove 144, and the receiving groove 144 is used to receive droplets to be tested (each receiving groove 144 is used to receive droplets to be tested of one sample), and the flexible partition wall 143 is used to prevent the droplets to be tested from overflowing the receiving groove 144, so as to avoid cross contamination of droplets to be tested of multiple samples.

[0046] Preferably, the flexible partition wall 143 is made of flexible, oil-resistant and heat-resistant materials such as silicone or rubber, and the flexible partition wall 143 and the flexible membrane 142 are fixedly connected by bonding or hot melting to completely seal the position where the bottom of the flexible partition wall 143 is connected to the flexible membrane 142 to prevent liquid leakage.

[0047] Furthermore, there are multiple receiving grooves 144, each receiving groove 144 is used to accommodate the droplets to be tested of a sample, and the multiple receiving grooves 144 work together to simultaneously realize the heating and cooling cycle of the droplets to be tested in multiple samples, thereby realizing nucleic acid detection of multiple samples at the same time and improving the efficiency of nucleic acid detection.

[0048] In this embodiment, the receiving grooves 144 are arranged in a rectangular shape, and the number of receiving grooves 144 is eight, and the eight receiving grooves 144 are arranged in a rectangular array to simultaneously detect nucleic acids of eight samples. However, this is not limited to this. In other embodiments, the receiving grooves 144 can be arranged in a circular shape or a triangular shape, and the number of receiving grooves 144 can be six or ten, and the shape and number of the receiving grooves 144 are not specifically limited.

[0049] Preferably, the heat conducting plate 130 is provided with an exhaust groove 132, which is arranged on the upper surface of the heat conducting plate 130 and extends to each corner of the heat conducting plate 130. The exhaust groove 132 is used for auxiliary exhaust to ensure that the flexible film 142 can be closely attached to the upper surface of the heat conducting plate 130. Specifically, the exhaust hole 131 is arranged on the bottom wall of the exhaust groove 132, and the vacuum mechanism 150 is connected with the exhaust groove 132 through the exhaust hole 131. The vacuum mechanism 150 is used to extract the air in the exhaust groove 132 through the exhaust hole 131 to form a stable vacuum field between the heat conducting plate 130 and the flexible film 142, so as to ensure that the flexible film 142 and the heat conducting plate 130 are closely attached.

[0050] It should be noted that the exhaust groove 132 is a groove with a small depth and a small width, and the flexible membrane 142 has a certain rigidity. Therefore, the flexible membrane 142 will not extend into the exhaust groove 132 and fit with the inner wall of the exhaust groove 132 under the suction force of the vacuum mechanism 150, but will remain in contact with the upper surface of the heat conducting plate 130 to achieve a higher flatness.

[0051] Preferably, the position of the flexible partition wall 143 corresponds to the position of the exhaust groove 132 , that is, the position of the flexible partition wall 143 on the flexible membrane 142 is the same as the position of the exhaust groove 132 on the heat conducting plate 130 to ensure the heating and cooling rate of the droplet to be tested in the containing groove 144 . Specifically, since the flexible membrane 142 will not fit closely with the inner wall of the exhaust groove 132, the heat transfer efficiency of the heat conductive plate 130 to the flexible membrane 142 at the position where the exhaust groove 132 is located is relatively low. Accordingly, the flexible partition wall 143 on the flexible membrane 142 is used to block the droplets to be tested in two adjacent containing grooves 144. There are no droplets to be tested at the position where the flexible partition wall 143 itself is located, and there is no need for high-precision temperature control. Therefore, the position of the flexible partition wall 143 is made to correspond to the position of the exhaust groove 132, which can not only improve the exhaust efficiency and ensure the vacuum effect, thereby ensuring that the flexible membrane 142 and the heat conductive plate 130 are closely fitted, but also avoid affecting the heat transfer efficiency of the droplets to be tested, thereby ensuring the heating and cooling rate of the droplets to be tested.

[0052] In this embodiment, the flexible partition wall 143 includes three horizontal bars 1431 and five vertical bars 1432, wherein the three horizontal bars 1431 are arranged in parallel and spaced apart, and the five vertical bars 1432 are arranged in parallel and spaced apart, each horizontal bar 1431 is connected to the five vertical bars 1432 at the same time, and each vertical bar 1432 is connected to the three horizontal bars 1431 at the same time, and the horizontal bars 1431 are arranged perpendicular to the vertical bars 1432 to jointly form eight accommodating grooves 144. Correspondingly, the exhaust groove 132 includes three transverse grooves 1321 and five longitudinal grooves 1322, wherein the three transverse grooves 1321 are arranged in parallel and spaced apart, and the five longitudinal grooves 1322 are arranged in parallel and spaced apart, each transverse groove 1321 is connected with the five longitudinal grooves 1322 at the same time, and each longitudinal groove 1322 is connected with the three transverse grooves 1321 at the same time, and the transverse grooves 1321 are arranged perpendicular to the longitudinal grooves 1322 to form eight heat transfer areas 133 on the upper surface of the heat conducting plate 130, and the positions of the eight heat transfer areas 133 correspond one by one to the positions of the eight receiving grooves 144, and each heat transfer area 133 is used to transfer heat to the droplets to be tested in a receiving groove 144 to realize the temperature rise and fall cycle operation.

[0053] Preferably, the heat conducting plate 130 is provided with a sealing groove 134, which is arranged at the edge of the heat conducting plate 130 and is also arranged outside the eight heat transfer areas 133. A sealing ring 160 is arranged in the sealing groove 134, and the sealing ring 160 abuts against the disk body 141. The sealing ring 160 is used to seal the gap between the disk body 141 and the heat conducting plate 130 to improve air tightness and ensure that a stable vacuum field is formed between the heat conducting plate 130 and the flexible film 142, thereby ensuring that the flexible film 142 is closely fitted to the heat conducting plate 130. Specifically, the sealing ring 160 is made of high temperature resistant silicone or rubber material.

[0054] The temperature control mechanism 120 includes a temperature rise and fall element 121, a temperature sensor 122 and a radiator 123. The temperature sensor 122 is connected to the heat conducting plate 130, and the temperature sensor 122 is used to detect the real-time temperature of the heat conducting plate 130 and to feed back to the controller to form a closed-loop temperature control and improve the accuracy of temperature control. The temperature rise and fall element 121 and the radiator 123 are both mounted on the base 110 and are both connected to the heat conducting plate 130. The temperature rise and fall element 121 is used to heat or cool the heat conducting plate 130, and the radiator 123 is used to cool the heat conducting plate 130. The controller can control the temperature rise and fall element 121 and the radiator 123 according to the real-time temperature of the heat conducting plate 130 to realize the temperature rise and fall cycle function of the droplet to be tested.

[0055] In this embodiment, the temperature rise and fall element 121 is a Peltier element, and the radiator 123 is an air-cooled radiator. However, this is not limited to this. In other embodiments, the temperature rise and fall element 121 may be a resistor, and the radiator 123 may be a water-cooled radiator. The types of the temperature rise and fall element 121 and the radiator 123 are not specifically limited.

[0056] The vacuum pumping mechanism 150 includes a vacuum pump 151, a three-way pipe 152 and an air pressure sensor 153. The first end of the three-way pipe 152 is connected to the air extraction hole 131, the second end of the three-way pipe 152 is connected to the vacuum pump 151, and the third end of the three-way pipe 152 is connected to the air pressure sensor 153. Specifically, the air pressure sensor 153 is used to detect the real-time vacuum degree and feedback to the controller to form a closed-loop vacuum degree control to improve the vacuum pumping accuracy. The vacuum pump 151 is used to extract air outward. The controller can control the vacuum pump 151 according to the real-time vacuum degree to ensure that a stable vacuum field is formed between the heat conducting plate 130 and the flexible membrane 142, thereby ensuring that the flexible membrane 142 and the heat conducting plate 130 are tightly fitted.

[0057] In this embodiment, the air extraction hole 131 is divided into an extension section 1311 and an exhaust section 1312 which are perpendicular and connected to each other, wherein the extension section 1311 is arranged within the enclosed range of the sealing groove 134, the depth of the sealing groove 134 is greater than the depth of the exhaust groove 132, and less than the depth of the extension section 1311, one end of the extension section 1311 is connected to the exhaust groove 132, and the other end is connected to the exhaust section 1312, the exhaust section 1312 is arranged across the sealing groove 134, and is connected to the three-way pipe 152. In this way, under the suction action of the vacuum pump 151, the air between the heat conducting plate 130 and the flexible membrane 142 can be drawn outward through the exhaust groove 132, the extension section 1311, the exhaust section 1312 and the three-way pipe 152 in sequence, thereby ensuring that the flexible membrane 142 and the heat conducting plate 130 are closely attached.

[0058] Please refer to Fig. 9 and Fig.10 Preferably, the temperature control device 100 further includes a positioning mechanism 170. The positioning mechanism 170 includes a positioning frame 171 and a positioning member 172. The positioning frame 171 is mounted on the base 110 and is simultaneously arranged outside the heat conducting plate 130 and the disk body 141 of the reaction disk 140. The base 110 is used to fix the position of the positioning frame 171. The positioning frame 171 is used to limit the disk body 141 to ensure that the reaction disk 140 is aligned with the heat conducting plate 130 when placed, thereby ensuring that the positions of the eight heat transfer areas 133 correspond to the positions of the eight accommodating grooves 144. In addition, the positioning frame 171 can also play a role in heat preservation, which isolates the temperature of the heat conducting plate 130 from the external environment temperature, ensures the heat transfer effect of the heat conducting plate 130 on the reaction disk 140, and improves the heating and cooling rate.

[0059] Furthermore, a limiting groove 1411 is provided on the outer wall of the disk body 141, and the positioning member 172 can be movably installed on the positioning frame 171 and cooperate with the limiting groove 1411 to fix the relative position of the disk body 141 and the positioning frame 171, thereby fixing the relative position of the disk body 141 and the heat conducting plate 130, which is convenient for subsequent vacuuming operations.

[0060] The positioning member 172 includes an elastic member 1721 and a ball 1722. The positioning frame 171 is provided with a positioning groove 1711, one end of the elastic member 1721 is connected to the bottom wall of the positioning groove 1711, and the other end is connected to the ball 1722. The ball 1722 is slidably arranged in the positioning groove 1711, and the elastic member 1721 is always in a compressed state to apply elastic force to the ball 1722, so that the ball 1722 has a tendency to move out of the positioning groove 1711. Specifically, the limiting groove 1411 is arranged in a conical shape, and the ball 1722 extends into the limiting groove 1411 and abuts against the side wall of the limiting groove 1411 to fix the relative position of the disk body 141 and the positioning frame 171, so as to prevent the disk body 141 from accidentally falling out of the positioning frame 171.

[0061] Preferably, the midpoint of the limiting groove 1411 is higher than the center of the ball 1722, that is, the axis of the cone of the limiting groove 1411 is higher than the center of the ball 1722. Since the axis of the cone of the limiting groove 1411 is higher, under the action of the elastic member 1721, the ball 1722 will exert a vertical downward force on the side wall of the limiting groove 1411, and the force will cause the plate body 141 to move downward and close to the sealing ring 160, so as to further improve the airtightness and ensure that a stable vacuum field is formed between the heat conducting plate 130 and the flexible membrane 142.

[0062] In this embodiment, the elastic member 1721 is a spring, and the round ball 1722 is a steel ball. However, this is not the only limitation. In other embodiments, the elastic member 1721 may be elastic rubber, and the round ball 1722 may be an aluminum ball. The materials of the elastic member 1721 and the round ball 1722 are not specifically limited. In addition, the elastic member 1721 and the round ball 1722 may be combined into one part, and the elasticity of the elastic member 1721 (plastic or sheet metal) may be used to drive the round ball 1722 to move.

[0063] In this embodiment, positioning is achieved by combining the ball 1722 and the conical limiting groove 1411, but it is not limited to this. In other embodiments, positioning can also be achieved by combining a wedge block and a bevel groove. The positioning method of the positioning member 172 is not specifically limited.

[0064] Furthermore, there are multiple elastic members 1721, balls 1722, positioning grooves 1711 and limiting grooves 1411. Each elastic member 1721 is connected to a ball 1722 and is arranged in a positioning groove 1711. Each ball 1722 can extend into a limiting groove 1411. Multiple limiting grooves 1411 are arranged at intervals on the outer wall of the disk body 141. Multiple elastic members 1721, multiple balls 1722, multiple positioning grooves 1711 and multiple limiting grooves 1411 work together to further improve the limiting effect and fix the relative position of the disk body 141 and the positioning frame 171.

[0065] In this embodiment, the number of the elastic member 1721, the round ball 1722, the positioning groove 1711 and the limiting groove 1411 are all four, wherein two limiting grooves 1411 are spaced apart on one side of the disk body 141, and the other two limiting grooves 1411 are spaced apart on the other side of the disk body 141. However, this is not limited thereto, and in other embodiments, the number of the elastic member 1721, the round ball 1722, the positioning groove 1711 and the limiting groove 1411 may all be six or eight, and the number of the elastic member 1721, the round ball 1722, the positioning groove 1711 and the limiting groove 1411 is not specifically limited.

[0066] It should be noted that during the use of the temperature control device 100, the reaction disk 140 is first placed on the heat conducting plate 130. During this process, the positioning frame 171 limits the reaction disk 140 to ensure that the placement position of the reaction disk 140 is aligned with the position of the heat conducting plate 130. The positioning member 172 positions the reaction disk 140 by cooperating with the limiting groove 1411 to fix the relative position of the reaction disk 140 and the positioning frame 171; then the vacuum mechanism 150 is started to extract the air between the flexible membrane 142 and the heat conducting plate 130 so that the flexible membrane 142 and the heat conducting plate 130 are tightly fitted; then the droplets to be tested are injected into the reaction disk 140; then the temperature control mechanism 120 is started to perform a temperature rise and fall cycle operation on the droplets to be tested in the reaction disk 140, which is convenient for subsequent observation and measurement, thereby realizing the nucleic acid detection function.

[0067] In the temperature control device 100 provided by the embodiment of the present invention, the temperature control mechanism 120 is installed on the base 110 and connected to the heat conducting plate 130. The reaction disk 140 is placed on the heat conducting plate 130. The reaction disk 140 includes a disk body 141 and a flexible membrane 142. The flexible membrane 142 is connected to the bottom of the disk body 141. The flexible membrane 142 is used to carry the droplets to be tested. The heat conducting plate 130 is provided with an exhaust hole 131. The vacuum mechanism 150 is connected to the exhaust hole 131. The vacuum mechanism 150 is used to extract the air between the flexible membrane 142 and the heat conducting plate 130 so that the flexible membrane 142 and the heat conducting plate 130 are tightly fitted. Compared with the prior art, the temperature control device 100 provided by the present invention uses a flexible membrane 142 connected to the bottom of the disk 141 and a vacuum mechanism 150 connected to the air extraction hole 131, so it can effectively reduce thermal resistance and heat capacity while ensuring the flatness of the droplet contact surface, increase the heating and cooling rate, ensure uniform temperature distribution, reduce material costs, and improve economic benefits. This makes the micro-droplet digital PCR instrument have high detection efficiency and good detection effect.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A temperature control device, characterized in that: The invention comprises a base, a temperature control mechanism, a heat conducting plate, a reaction disk and a vacuum mechanism, wherein the temperature control mechanism is installed on the base and connected to the heat conducting plate, the reaction disk is placed on the heat conducting plate, the reaction disk comprises a disk body and a flexible membrane, the flexible membrane is connected to the bottom of the disk body, the flexible membrane is used to carry droplets to be tested, the heat conducting plate is provided with an air extraction hole, the vacuum mechanism is connected to the air extraction hole, and the vacuum mechanism is used to extract the air between the flexible membrane and the heat conducting plate so that the flexible membrane and the heat conducting plate are closely fitted.

2. The temperature control device according to claim 1, characterized in that: The reaction disk further comprises a flexible partition wall, wherein the flexible partition wall is connected to the flexible membrane, and the flexible partition wall and the flexible membrane together form at least one containing groove, and the containing groove is used to contain a droplet to be measured.

3. The temperature control device according to claim 2, characterized in that: The heat conducting plate is provided with an exhaust groove, and the exhaust hole is arranged on the bottom wall of the exhaust groove.

4. The temperature control device according to claim 3, characterized in that: The position of the flexible partition wall corresponds to the position of the exhaust groove.

5. The temperature control device according to claim 1, characterized in that: The heat conducting plate is provided with a sealing groove, a sealing ring is arranged in the sealing groove, and the sealing ring abuts against the disk body.

6. The temperature control device according to claim 1, characterized in that: The temperature control mechanism includes a temperature rising and falling element, a temperature sensor and a radiator. The temperature sensor is connected to the heat conducting plate. The temperature sensor is used to detect the real-time temperature of the heat conducting plate. The temperature rising and falling element and the radiator are both installed on the base and connected to the heat conducting plate. The temperature rising and falling element is used to heat or cool the heat conducting plate, and the radiator is used to cool the heat conducting plate.

7. The temperature control device according to claim 1, characterized in that: The vacuum extraction mechanism includes a vacuum pump, a three-way pipe and an air pressure sensor. The first end of the three-way pipe is connected to the air extraction hole, the second end of the three-way pipe is connected to the vacuum pump, and the third end of the three-way pipe is connected to the air pressure sensor. The vacuum pump is used to extract air outwards, and the air pressure sensor is used to detect the real-time vacuum degree.

8. The temperature control device according to claim 1, characterized in that: The temperature control device also includes a positioning mechanism, which includes a positioning frame and a positioning member. The positioning frame is installed on the base and is also surrounded by the heat conducting plate and the outside of the disk body. The disk body is provided with a limiting groove. The positioning member can be movably installed on the positioning frame and cooperate with the limiting groove.

9. The temperature control device according to claim 8, characterized in that: The positioning member includes an elastic member and a round ball. The positioning frame is provided with a positioning groove. One end of the elastic member is connected to the bottom wall of the positioning groove, and the other end is connected to the round ball. The round ball is slidably arranged in the positioning groove. The limiting groove is arranged in a conical shape, the midpoint of the limiting groove is higher than the center of the ball, the ball extends into the limiting groove and abuts against the side wall of the limiting groove.

10. A droplet digital PCR instrument, characterized in that: Comprising a temperature control device as described in any one of claims 1 to 9.

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