Droplet Reader

Abstract

The present invention discloses a droplet reader, comprising: a liquid storage component, a liquid delivery system, a sample loading component and an optical detection component; the liquid storage component is used to provide detection oil and collect waste oil, the sample loading component is used to absorb the sample droplets to be tested placed in the droplet reader, and transport the sample droplets to be tested through the liquid delivery system so that the droplets are arranged in sequence through the detection position of the optical detection component, so as to perform fluorescence detection on the sample droplets to be tested. The present invention can realize the three-dimensional movement of the injection needle through a three-dimensional mobile mechanical arm to load samples; by setting a buffer connection block, the defect of insufficient sample suction caused by the depth error of each sample storage hole can be overcome, and the injection needle can penetrate into the bottom of each sample storage hole to ensure complete absorption of the sample; by optimizing the liquid path structure, the control difficulty of the system can be limitedly reduced, while improving the robustness of the system; the droplet reader of the present invention optimizes the structure, the structure layout of the whole instrument is clear, and it is easy to disassemble and assemble.

Description

Technical Field

[0001] The invention relates to the technical field of biological detection, and in particular to a droplet reader. Background Art

[0002] Highly sensitive and rapid nucleic acid detection technology has strong advantages in the field of low-abundance nucleic acid detection such as cancer molecular marker discovery, infectious diseases, and genetic disease research. It is of great significance for disease onset research, early diagnosis, and personalized treatment! Typical nucleic acid detection technologies include fluorescent quantitative PCR, molecular hybridization, and gene sequencing technology. The detection accuracy of fluorescent quantitative PCR and molecular hybridization technology is limited, and the cost of gene testing is high and time-consuming. Digital PCR (Digital PCR-dPCR) technology is a new nucleic acid detection and quantification method. It uses an absolute quantitative method and does not rely on standard curves and reference samples to directly detect the copy number of the target sequence. The principle of digital PCR: a standard PCR reaction is distributed to a large number of tiny reactors, and each reactor contains or does not contain one or more copies of the target molecule (DNA template) to achieve "single molecule template PCR amplification". After the amplification is completed, the copy number of the target sequence is "counted" by the number of positive reactors. The digital PCR process includes: droplet generation → coating → amplification → droplet reading.

[0003] Among them, droplet generation is used to generate thousands of droplets, which is achieved using a droplet generator; coating is used to coat 96 droplet samples in a 96-well plate to prevent the samples from being dried out or otherwise damaged during the subsequent PCR process, which is achieved using a laminating machine, which is simply a simple mechanical heating and gluing process; amplification is achieved using a PCR instrument, which is essentially a temperature cycling process used to replicate the DNA in droplet samples. There are mature PCR amplifiers on the market, such as Ebende and Longji; droplet reading is to arrange the droplets individually in sequence through the optical detection area, and detect the negative and positive signals of each droplet by optical means, and finally calculate the concentration of the target gene in the original sample according to the mathematical calculation formula of the Poisson distribution, thereby achieving the purpose of detecting the target gene in the sample. Droplet reading can be achieved by a reader.

[0004] Four instruments are needed in the digital PCR process: a droplet generator, a laminator, a PCR instrument, and a reader. Among these four instruments, the laminator and the PCR instrument have lower technical barriers, while the droplet generator and the reader have higher technical barriers. The reader is used to arrange the droplets in the sample in sequence and perform fluorescence detection, and calculate the concentration of the original sample through the post-data processing algorithm. Existing readers have many shortcomings, such as the complex structure of the whole machine, the inconvenient use of the devices for providing test oil and recycling waste oil, the low utilization rate of the samples to be tested, etc., so a more reliable solution is now needed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a droplet reader in view of the deficiencies in the above-mentioned prior art.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a droplet reader, comprising: a liquid storage component, a liquid delivery system, a sample loading component and an optical detection component;

[0007] The liquid storage component is used to provide detection oil and collect waste oil, and the sample loading component is used to absorb the sample droplets to be tested placed in the droplet reader, and transport the sample droplets to be tested through the liquid delivery system so that the droplets to be tested are arranged in sequence through the detection position of the optical detection component to perform fluorescence detection on the sample droplets to be tested.

[0008] Preferably, the liquid storage assembly comprises a liquid storage base, a liquid tank box slidably disposed on the liquid storage base, and at least two liquid storage tanks disposed in the liquid tank box; the at least two liquid storage tanks comprise at least one detection oil tank and one waste oil tank;

[0009] The sample loading component comprises a three-dimensional mobile mechanical arm, a sample storage device and a sample injection needle arranged on the three-dimensional mobile mechanical arm; the sample storage device is used for storing droplets of samples to be tested.

[0010] Preferably, the liquid delivery system includes an oil pipeline connected to the detection oil tank, an oil pump arranged on the oil pipeline, a detection chip connected to the output end of the oil pipeline through an oil inlet, a sample pump, a sample pipeline connected between the sample pump and the sampling port of the detection chip, a reversing valve arranged on the sample pipeline, a sample suction pipeline connected between the reversing valve and the sampling needle, a waste oil pipeline connected between the total outlet of the detection chip and the waste oil tank, and a solenoid valve arranged on the waste oil pipeline.

[0011] Preferably, the reversing valve comprises at least a first port, a second port and a third port, and can be switched between a first state and a second state, wherein the first state is: the first port and the second port are connected, and the second port and the third port are disconnected; the second state is: the second port and the third port are connected, and the first port and the second port are disconnected;

[0012] The second port is connected to the sample pump through the sample delivery pipeline, the third port is connected to the sample inlet of the detection chip through the sample delivery pipeline, and the first port is connected to the sample injection needle through the sample suction pipeline.

[0013] Preferably, the detection chip includes two oil inlets, and the detection chip has a cross-type microfluidic structure inside, and the microfluidic structure forms the sample inlet, two oil inlets and a total outlet on the four sides of the detection chip respectively, and the two oil inlets are symmetrically distributed on both sides of the sample inlet.

[0014] Preferably, it further comprises a bottom plate, and the liquid storage component, liquid delivery system, sample loading component and optical detection component are all arranged on the bottom plate;

[0015] The liquid storage base is fixedly connected to the bottom plate, and the liquid storage tank comprises a tank body, a tank opening arranged on the top of the tank body, a joint pipe arranged on the tank opening, a joint converter with a lower end inserted into the joint pipe and an upper end extending out, and a tank cover threadedly matched with the joint pipe for fixing the lower end of the joint converter in the joint pipe;

[0016] The joint converter is provided with a plurality of channels for connecting the inside of the tank with the outside;

[0017] The channel includes a horizontal channel and a vertical channel that are interconnected. The horizontal channel forms an external pipeline interface on the side of the upper end of the joint converter, and the vertical channel forms an internal pipeline interface on the lower end surface of the joint converter.

[0018] Preferably, a through hole is provided in the middle of the can cover, and an annular flange is provided on the inner edge of the upper end thereof;

[0019] An annular baffle is provided on the outer periphery of the joint converter, and the outer diameter of the annular baffle is smaller than the diameter of the through hole and larger than the inner diameter of the annular flange;

[0020] The joint converter is inserted into the joint pipe, and after the tank cover is threadedly connected to the joint pipe, the annular flange presses against the upper surface of the annular baffle.

[0021] Preferably, the three-dimensional mobile mechanical arm includes an X-axis motion component arranged on the base plate, a Y-axis motion component arranged on the X-axis motion component, and a Z-axis motion component arranged on the Y-axis motion component;

[0022] The Z-axis motion assembly includes a Z-axis mounting plate arranged on the Y-axis motion assembly, a Z-axis motor arranged on the Z-axis mounting plate, a Z-axis lead screw drivingly connected to the Z-axis motor, and a Z-axis sleeve threadedly matched with the Z-axis lead screw;

[0023] The injection needle is connected to the Z-axis sliding sleeve through a buffer connection block.

[0024] Preferably, a threaded hole is provided on the buffer connection block, a boss is provided on the upper part of the Z-axis sliding sleeve, a through hole is provided on the boss, a screw with a diameter smaller than the through hole is inserted into the through hole, the lower part of the screw is fixedly connected to the threaded hole, and a nut with a diameter larger than the through hole is provided on the upper end of the screw; a spring is sleeved on the Z-axis sliding sleeve, the upper end of the spring contacts the bottom surface of the boss, and the lower end of the spring contacts the buffer connection block;

[0025] The buffer connection block is provided with a through hole having a diameter larger than that of the Z-axis screw rod for the Z-axis screw rod to pass through, and the upper portion of the buffer connection block is also provided with a receiving groove for receiving the Z-axis sliding sleeve.

[0026] Preferably, a detection pipeline section is connected between the total outlet of the detection chip and the waste liquid pipeline, and the detection pipeline section is located at the detection position of the optical detection component;

[0027] The optical detection component includes at least two laser light sources, a transmission light path for transmitting light emitted by the at least two laser light sources to the sample droplets to be tested on the detection pipeline section, at least two lateral detectors for collecting fluorescence generated by the sample droplets to be tested on the detection pipeline section, and a forward detector for collecting laser light after passing through the sample droplets to be tested on the detection pipeline section.

[0028] The beneficial effects of the present invention are:

[0029] The liquid storage assembly of the present invention can keep the position of the joint converter basically unchanged during the process of unscrewing the tank cover, and the pipeline connected to the joint converter will not be twisted and entangled due to the rotation of the tank cover, so it is convenient to open the tank cover; the sliding device is arranged in a high and low position, which can save space and is easy to install and replace the liquid storage tank; by arranging magnets and iron sheets, the stability of the liquid tank box after being pushed into the base can be increased; by arranging a liquid level sensor, the liquid level in the tank body can be monitored;

[0030] The present invention can realize the three-dimensional movement of the injection needle through the three-dimensional mobile mechanical arm to load the sample; by setting the buffer connection block, the defect of insufficient sample absorption caused by the depth error of each sample storage hole can be overcome, and the injection needle can penetrate into the bottom of each sample storage hole to ensure complete absorption of the sample;

[0031] The present invention can reduce the control difficulty of the system to a limited extent and improve the robustness of the system through the optimized liquid circuit structure;

[0032] The present invention can realize double fluorescence detection or even more fluorescence detection, greatly improving the utilization rate of samples;

[0033] The micro-droplet reader of the present invention adopts a modular design concept, optimizes the structure, and has a clear structure layout and is easy to assemble and disassemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the structure of the microdroplet reader of the present invention;

[0035] Figure 2 It is a structural schematic diagram of another perspective of the micro-droplet reader of the present invention;

[0036] Figure 3 It is a structural schematic diagram of the liquid storage assembly of the present invention;

[0037] Figure 4 It is a structural schematic diagram of the liquid storage assembly of the present invention from another perspective;

[0038] Figure 5 It is a structural schematic diagram of the liquid storage assembly of the present invention from a side perspective;

[0039] Figure 6 It is a structural schematic diagram of another side view of the liquid storage assembly of the present invention;

[0040] Figure 7 It is a structural schematic diagram of the liquid storage tank of the present invention;

[0041] Figure 8 It is a schematic diagram of the exploded structure of the liquid storage tank of the present invention;

[0042] Fig. 9 It is a cross-sectional structural schematic diagram of the connector converter of the present invention;

[0043] Fig.10 It is a partial cross-sectional structural schematic diagram of the liquid storage tank of the present invention;

[0044] Fig.11 It is a schematic diagram of the liquid circuit principle of the liquid delivery system of the present invention;

[0045] Fig.12 It is a structural schematic diagram of the detection chip of the present invention;

[0046] Fig.13 is a schematic cross-sectional structural diagram of the detection chip of the present invention;

[0047] Fig.14 It is a structural schematic diagram of the three-dimensional mobile mechanical arm of the present invention;

[0048] Fig.15 A schematic structural diagram of the three-dimensional mobile mechanical arm of the present invention from another perspective;

[0049] Fig.16 It is a structural schematic diagram of the Z-axis motion assembly and the buffer connection block of the present invention;

[0050] Fig.17It is a schematic diagram of the exploded structure of the Z-axis motion assembly and the buffer connection block of the present invention;

[0051] Fig.18 It is a schematic cross-sectional structural diagram of a buffer connection block of the present invention;

[0052] Fig.19 It is a structural schematic diagram of the sample storage device of the present invention;

[0053] Fig. 20 It is a schematic cross-sectional structural diagram of the sample storage device of the present invention;

[0054] Fig.21 This is a light path diagram of the optical detection component of the present invention.

[0055] Description of reference numerals:

[0056] 1—liquid storage component;

[0057] 10—liquid storage base; 100—base plate; 101—first side plate; 102—second side plate; 103—installation space; 104—pillar;

[0058] 11—Liquid tank box;

[0059] 12—liquid storage tank; 120—tank body; 121—tank mouth; 122—connector pipe; 123—connector converter; 124—tank cover; 125—channel; 127—liquid level sensor; 128—L-shaped fixing plate; 129—mounting frame; 1230—annular baffle; 1240—through hole; 1241—annular flange; 1250—horizontal channel; 1251—vertical channel; 1252—external pipeline interface; 1253—internal pipeline interface; 1290—horizontal mounting plate; 1291—high vertical mounting plate; 1292—low vertical mounting plate; 1293—mounting through hole; 1294—baffle; 1295—magnet;

[0060] 13 - sliding device;

[0061] 14—Inspecting oil tanks;

[0062] 15—waste oil tank;

[0063] 2—Liquid delivery system;

[0064] 20—oil delivery pipeline; 21—oil pump; 22—detection chip; 23—sample pump; 24—sample delivery pipeline; 25—reversing valve; 26—sample suction pipeline; 27—waste oil pipeline; 28—solenoid valve; 220—inlet; 221—oil inlet; 222—main outlet; 223—detection pipeline section; 250—first port; 251—second port; 252—third port;

[0065] 3—sample loading assembly;

[0066] 30—3D mobile robot;

[0067] 300—X-axis motion assembly; 3000—X-axis motor; 3001—X-axis screw rod; 3002—X-axis slider; 3003—X-axis optical coupler; 3004—X baffle;

[0068] 301—Y-axis motion assembly; 3010—Y-axis mounting plate; 3011—Y-axis motor; 3012—Y-axis lead screw; 3013—Y-axis slider; 3014—Y-axis optical coupler; 3015—Y baffle;

[0069] 302—Z-axis motion assembly; 3020—Z-axis mounting plate; 3021—Z-axis motor; 3022—Z-axis screw rod; 3023—Z-axis sleeve; 3024—boss; 3025—through hole; 3026—screw; 3027—nut; 3028—spring; 3029—Z-axis optical coupler;

[0070] 303—Mounting bracket;

[0071] 31 - sample storage device; 310 - orifice plate base; 311 - sample storage orifice plate; 312 - pressure plate;

[0072] 32—injection needle;

[0073] 33—buffer connection block; 330—through hole; 331—accommodation groove; 332—Z baffle; 333—threaded hole;

[0074] 4—optical detection assembly; 40—first laser; 41—second laser; 42—first lateral detector; 43—second lateral detector; 44—transmission optical path; 45—second dichroic mirror; 46—first filter; 47—second filter; 49—forward detector; 440—first reflector; 441—first dichroic mirror; 442—focusing lens;

[0075] 5—Bottom plate. DETAILED DESCRIPTION

[0076] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0077] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0078] like Figure 1-2 As shown, a droplet reader of this embodiment includes: a liquid storage component 1, a liquid delivery system 2, a sample loading component 3 and an optical detection component 4;

[0079] The liquid storage component 1 is used to provide test oil and collect waste oil, and the sample loading component 3 is used to absorb the test sample droplets placed in the droplet reader, and transport the test sample droplets through the liquid delivery system 2 so that the test sample droplets are arranged in sequence through the detection position of the optical detection component 4, so as to perform fluorescence detection on the test sample droplets. The test oil is used to cause the test sample droplets to be arranged in sequence through the detection position to achieve fluorescence detection of each droplet. The optical detection component 4 emits a laser to irradiate the test sample droplets, so that they are excited to produce fluorescence, and collects the fluorescence signal, and after subsequent data processing, realizes sample detection.

[0080] The liquid storage assembly 1 includes a liquid storage base 10, a liquid tank box 11 slidably disposed on the liquid storage base 10, and at least two liquid storage tanks 12 disposed in the liquid tank box 11; the at least two liquid storage tanks 12 include at least one detection oil tank 14 and one waste oil tank 15;

[0081] The sample loading assembly 3 comprises a three-dimensional mobile mechanical arm 30 , a sample storage device 31 and a sample injection needle 32 arranged on the three-dimensional mobile mechanical arm 30 ; the sample storage device 31 is used to store the sample droplets to be tested.

[0082] In one embodiment, referring to Figure 11-13 The liquid delivery system 2 includes an oil delivery pipeline 20 connected to the detection oil tank 14, an oil pump 21 arranged on the oil delivery pipeline 20, a detection chip 22 connected to the output end of the oil delivery pipeline 20 through an oil inlet 221, a sample pump 23, a sample delivery pipeline 24 connected between the sample pump 23 and the sample inlet 220 of the detection chip 22, a reversing valve 25 arranged on the sample delivery pipeline 24, a sample suction pipeline 26 connected between the reversing valve 25 and the sample injection needle 32, a waste oil pipeline 27 connected between the total outlet 222 of the detection chip 22 and the waste oil tank 15, and a solenoid valve 28 arranged on the waste oil pipeline 27.

[0083] The reversing valve 25 at least includes a first port 250, a second port 251 and a third port 251, and can switch between a first state and a second state. The first state is: the first port 250 and the second port 251 are connected, and the second port 251 and the third port 251 are disconnected; the disconnected second state is: the second port 251 and the third port 251 are connected, and the first port 250 and the second port 251 are disconnected; the second port 251 is connected to the sample pump 23 through the sample delivery pipeline 24, the third port 251 is connected to the injection port 220 of the detection chip 22 through the sample delivery pipeline 24, and the first port 250 is connected to the injection needle 32 through the sample suction pipeline 26. In this embodiment, the reversing valve 25 is a three-position two-way reversing valve 25.

[0084] The detection chip 22 can be a microfluidic chip made of transparent PMMA material.

[0085] The detection chip 22 includes two oil inlets 221 , and the detection chip 22 has a cross-shaped microfluidic structure inside. The microfluidic structure forms an inlet 220 , two oil inlets 221 and a total outlet 222 on the four sides of the detection chip 22 , and the two oil inlets 221 are symmetrically distributed on both sides of the inlet 220 .

[0086] The process of aspirating the sample is as follows: the electromagnetic valve 28 is closed, the first port 250 and the second port 251 are connected, the sample pump 23 works to aspirate the sample back, and the sample droplets to be tested absorbed by the injection needle 32 pass through the sample aspiration pipeline 26, the first port 250, and the second port 251 in sequence and are filled in the sample delivery pipeline 24;

[0087] Detection process (injecting samples into the detection chip 22): the solenoid valve 28 opens, and the reversing valve 25 switches from the first state to the second state, that is, the second port 251 and the third port 251 are connected, and the first port 250 and the second port 251 are disconnected; the oil pump 21 works to push the detection oil forward, and the sample pump 23 works to push the droplets of the sample to be tested in the sample delivery pipeline 24 to move forward; in the detection chip 22, the channel 125 is a cross structure, and the droplets of the sample to be tested move forward, and the detection oil shears the droplets of the sample to be tested from both vertical sides, and disperses the droplets in the sample one by one. Of course, the cross structure can also be replaced by a T-type structure or a Y-type structure, that is, the detection oil is sheared only from one side. It can be understood that the cross structure should be the most preferred option. By optimizing the liquid path structure, the control difficulty of the system can be reduced to a limited extent.

[0088] In one embodiment, referring to Figure 3-10 , further comprising a shell (not shown in the figure) and a bottom plate 5, wherein the liquid storage component 1, the liquid delivery system 2, the sample loading component 3 and the optical detection component 4 are all arranged on the bottom plate 5 and are located inside the shell;

[0089] The liquid storage base 10 is fixedly connected to the bottom plate 5, and the liquid storage tank 12 includes a tank body 120, a tank mouth 121 arranged on the top of the tank body 120, a joint pipe 122 arranged on the tank mouth 121, a joint converter 123 whose lower end is inserted into the joint pipe 122 and whose upper end protrudes, and a tank cover 124 threadedly matched with the joint pipe 122 for fixing the lower end of the joint converter 123 in the joint pipe 122;

[0090] The connector converter 123 is provided with a plurality of channels 125 for connecting the inside of the tank 120 with the outside.

[0091] An L-shaped fixing plate 128 is fixedly connected to the joint converter 123 , and the other end of the L-shaped fixing plate 128 is connected to the tank body 120 .

[0092] The channel 125 includes a horizontal channel 1250 and a vertical channel 1251 which are interconnected. The horizontal channel 1250 forms an external pipeline interface 1252 on the side of the upper end of the joint converter 123, and the vertical channel 1251 forms an internal pipeline interface 1253 on the lower end surface of the joint converter 123.

[0093] A through hole 1240 is provided in the middle of the tank cover 124, and an annular flange 1241 is provided on the inner edge of the upper end thereof; an annular baffle 1230 is provided on the outer periphery of the joint converter 123, and the outer diameter of the annular baffle 1230 is smaller than the diameter of the through hole 1240 and larger than the inner diameter of the annular flange 1241; the joint converter 123 is inserted into the joint pipe 122, and after the tank cover 124 and the joint pipe 122 are threadedly connected, the annular flange 1241 presses on the upper surface of the annular baffle 1230.

[0094] Since the joint converter 123 is connected to the tank body 120 through the L-shaped fixing plate 128, it will not rotate, and can prevent the pipeline connected thereto from twisting and winding; and it will not fall downward. And the L-shaped fixing plate 128 has a certain elasticity, so that the joint converter 123 can move vertically for a small distance. When tightening the tank cover 124, the internal thread of the tank cover 124 cooperates with the external thread of the joint pipe 122, the tank cover 124 rotates, and the joint converter 123 does not rotate. The tank cover 124 rotates and moves downward, and the annular baffle 1230 of the joint converter 123 is pressed downward by the annular flange 1241 (the joint converter 123 moves slightly downward), thereby fixing the joint converter 123. Since the volume of the tank is limited, it needs to be replaced regularly. The detection oil is a stable detection oil, and the waste liquid is the cost. Both are dedicated and there will be no cross-contamination phenomenon. Therefore, when changing the liquid storage tank 12, the cover (including the tank cover 124 and the joint converter 123) is not replaced, which eliminates the trouble of disassembling the pipeline (the pipeline is connected to the joint converter 123). In this embodiment, the position of the joint converter 123 can be kept basically unchanged during the process of unscrewing the tank cover 124, and the pipeline connected to the joint converter 123 will not be twisted or entangled due to the rotation of the tank cover 124.

[0095] Furthermore, a liquid level sensor 127 is provided on the tank body 120. The liquid level sensor 127 uses a non-contact sensor (such as a capacitive or inductive) to monitor the liquid level in the tank body 120, such as a liquid level sensor 127 of model XKC-Y26. The monitoring result of the liquid level sensor 127 can be transmitted to the whole machine display of the droplet reader, which can remind the user to replace the liquid storage tank 12 in time.

[0096] Furthermore, the liquid tank box 11 is slidably connected to the base through a sliding device 13; a mounting frame 129 is fixedly connected to the bottom of the liquid tank box 11, and the mounting frame 129 includes a horizontal mounting plate 1290 fixedly connected to the bottom of the liquid tank box 11 and a high vertical mounting plate 1291 and a low vertical mounting plate 1292 fixedly connected to both sides of the horizontal mounting plate 1290, and the height of the bottom edge of the high vertical mounting plate 1291 is higher than the height of the bottom edge of the low vertical mounting plate 1292. The liquid storage base 10 includes a base plate 100 and a first side plate 101 and a second side plate 102 fixedly connected to both sides of the base plate 100. The height of the second side plate 102 is smaller than that of the first side plate 101. An installation space 103 is reserved between the upper end of the second side plate 102 and the bottom of the liquid tank box 11 to facilitate the installation of the sliding device 13; the sliding device 13 includes a higher point arranged between the mounting frame 129 and the base, one of which is arranged between the high vertical mounting plate 1291 and the first side plate 101, and the other is arranged between the low vertical mounting plate 1292 and the second side plate 102.

[0097] In a preferred embodiment, the sliding device 13 is a drawer-type slide rail, one half of which is connected to the base, and the other half is connected to the mounting frame 129, and the two halves are slidable relative to each other. In another embodiment, the sliding device 13 can also be in the form of a combination of a slider and a slide rail, that is, the slider and the slide rail are respectively arranged on the liquid storage base 10 and the mounting frame 129, so as to achieve a slidable connection between the base and the mounting frame 129.

[0098] The liquid storage device of this embodiment is mainly used in a droplet reader. The liquid storage tank 12 often needs to be replaced. In order to save height space, the liquid tank box 11 is pulled out horizontally from the side for replacement. The sliding device 13 is arranged in a high and low position, which can save space and is easy to install. Furthermore, the part of the low-position vertical mounting plate 1292 in the mounting space 103 is provided with a mounting through hole 30251293, and the mounting through hole 30251293 can facilitate the installation of the sliding device 13 on the high-position vertical mounting plate 1291.

[0099] Among them, a baffle 1294 is fixedly connected to the inner end of the horizontal mounting plate 1290, and a magnet 1295 is arranged on the baffle 1294. A support 104 is arranged at the inner end of the base, and an iron sheet (not shown in the figure) for attracting the magnet 1295 is arranged on the support 104. After the liquid tank box 11 is pushed into the base, the magnet 1295 is attracted to the iron sheet, so that the liquid tank box 11 remains relatively fixed in the base.

[0100] In one embodiment, referring to Figure 14-20 The three-dimensional mobile mechanical arm 30 includes an X-axis motion component 300 disposed on the base plate 5, a Y-axis motion component 301 disposed on the X-axis motion component 300, and a Z-axis motion component 302 disposed on the Y-axis motion component 301;

[0101] The Z-axis motion assembly 302 includes a Z-axis mounting plate 3020 disposed on the Y-axis motion assembly 301, a Z-axis motor 3021 disposed on the Z-axis mounting plate 3020, a Z-axis screw rod 3022 drivingly connected to the Z-axis motor 3021, and a Z-axis sleeve 3023 threadedly matched with the Z-axis screw rod 3022;

[0102] The injection needle 32 is connected to the Z-axis sliding sleeve 3023 through the buffer connection block 33 .

[0103] The sample storage device 31 includes a well plate base 310, a sample storage well plate 311 disposed on the well plate base 310, and a pressing plate 312 disposed on the sample storage well plate 311. The sample storage well plate 311 is provided with a plurality of sample storage holes for storing samples, and a 96-well plate is selected in this embodiment. The well plate base 310 is provided with a plurality of opening structures that match the bottom of the sample storage well plate 311, and the pressing plate 312 is also provided with a plurality of openings corresponding to the positions and numbers of the sample storage holes above the sample storage well plate 311. A conventional clamping device can also be provided on the pressing plate 312 to clamp and fix the sample storage well plate 311 on the well plate base 310 through the pressing plate 312. During detection, the droplets to be tested are first stored in the well plate, and then the well plate is placed in the droplet reader, and then the three-dimensional mobile mechanical arm 30 is used to absorb the sample in the well plate for detection.

[0104] Among them, due to the existence of processing errors of the sample storage hole plate 311, the depth of each sample storage hole may be different. If the injection needle 32 moves to the same height each time, it is easy to cause the sample in the sample storage hole to fail to be completely absorbed, resulting in sample waste. For some precious samples, this problem needs to be solved. In the present application, the buffer connection block 33 can solve this problem.

[0105] Specifically, in a preferred embodiment, a threaded hole 333 is provided on the buffer connection block 33, a boss 3024 is provided on the upper part of the Z-axis sliding sleeve 3023, a through hole 3025 is provided on the boss 3024, a screw 3026 with a diameter smaller than the through hole 3025 is inserted into the through hole 3025, the lower part of the screw 3026 is fixedly connected to the threaded hole 333, and a nut 3027 with a diameter larger than the through hole 3025 is provided on the upper end of the screw 3026; A spring 3028 is sleeved on the sleeve 3023, the upper end of the spring 3028 contacts the bottom surface of the boss 3024, and the lower end of the spring 3028 contacts the buffer connection block 33; the buffer connection block 33 is provided with a through hole 330 with a diameter larger than the Z-axis screw rod 3022 for the Z-axis screw rod 3022 to pass through, and the upper part of the buffer connection block 33 is also provided with a receiving groove 331 for accommodating the Z-axis sleeve 3023, and a threaded hole 333 is opened downward from the bottom of the groove.

[0106] Its working principle is as follows: the Z-axis screw rod 3022 rotates, driving the Z-axis sleeve 3023 to slide up and down. When the Z-axis sleeve 3023 slides downward, the Z-axis sleeve 3023 drives the buffer connection block 33 and the injection needle 32 thereon to move downward together through the spring 3028 and the self-gravity of the buffer connection block 33. When the injection needle 32 contacts the bottom inner wall of the sample storage hole, the Z-axis sleeve 3023 will continue to move downward a short distance. When the Z-axis sleeve 3023 continues to move downward, the boss 3024 squeezes downward and compresses the spring 3028, and the upper part of the screw 3026 threadedly connected to the buffer connection block 33 extends upward relative to the boss 3024. When the limit distance of the downward movement of the Z-axis sliding sleeve 3023 is preset, the Z-axis sliding sleeve 3023 needs to move downward a short distance after the injection needle 32 contacts the bottom inner wall of the sample storage hole, so that even if there is an error in the depth of each sample storage hole, the injection needle 32 can penetrate into the bottom of each sample storage hole to ensure complete absorption of the sample. On the other hand, after the injection needle 32 contacts the bottom inner wall of the sample storage hole, the spring 3028 applies a flexible force to convert the contact between the injection needle 32 and the bottom inner wall of the sample storage hole into a flexible contact, which can prevent the injection needle 32 from being damaged.

[0107] The X-axis motion assembly 300, the Y-axis motion assembly 301, and the Z-axis motion assembly 302 realize the motion in the three directions of XYZ respectively, and in this embodiment, a screw motor mechanism is adopted. Specifically, a mounting bracket 303 is provided on the bottom plate 5, and the X-axis motion assembly 300 includes an X-axis motor 3000 provided on the mounting bracket 303, an X-axis screw rod 3001 drivingly connected to the X-axis motor 3000, and an X-axis slider 3002 (with a threaded hole 333 provided inside) sleeved on the X-axis screw rod 3001 and threadedly matched with the X-axis screw rod 3001. The X-axis screw rod 3001 rotates so that the X-axis slider 3002 threadedly matched with it moves along the X-axis. The Y-axis motion assembly 301 includes a Y-axis mounting plate 3010 disposed on the X-axis slider 3002, a Y-axis motor 3011 disposed on the Y-axis mounting plate 3010, a Y-axis lead screw 3012 drivingly connected to the Y-axis motor 3011, and a Y-axis slider 3013 (with a threaded hole 333 inside) sleeved on the Y-axis lead screw 3012 and threadedly matched with the Y-axis lead screw 3012; the Y-axis lead screw 3012 rotates so that the Y-axis slider 3013 threadedly matched with it moves along the Y-axis. The Z-axis mounting plate 3020 of the Z-axis motion assembly 302 is disposed on the Y-axis slider 3013. The Z-axis lead screw 3022 rotates so that the Z-axis sleeve 3023 (with a threaded hole 333 inside) threadedly matched with it moves along the Z-axis.

[0108] Furthermore, the X-axis motion assembly 300, the Y-axis motion assembly 301, and the Z-axis motion assembly 302 are all provided with positioning mechanisms, and the positioning mechanisms include slot-type optical couplers and baffles, which are used to achieve positioning in various directions. Specifically, the mounting bracket 303 is provided with an X-axis optical coupler 3003, and the X-axis slider 3002 is provided with an X baffle 3004 that cooperates with the X-axis optical coupler 3003; the Y-axis mounting plate 3010 is provided with a Y-axis optical coupler 3014, and the Y-axis slider 3013 is provided with a Y baffle 3015 that cooperates with the Y-axis optical coupler 3014; the Z-axis mounting plate 3020 is provided with a Z-axis optical coupler 3029, and the buffer connection block 33 is provided with a Z baffle 332 that cooperates with the Z-axis optical coupler 3029.

[0109] In one embodiment, referring to Figure 12-13 A detection pipeline section 223 is connected between the total outlet 222 of the detection chip 22 and the waste liquid pipeline, and the detection pipeline section 223 is located at the detection position of the optical detection component 4.

[0110] The optical detection assembly 4 includes at least two laser light sources, a transmission optical path 44 for transmitting light emitted by the at least two laser light sources to the sample droplets to be detected on the detection pipeline section 223, at least two lateral detectors for collecting fluorescence generated by the sample droplets to be detected on the detection pipeline section 223 when excited, and a forward detector 49 for collecting laser light after passing through the sample droplets to be detected on the detection pipeline section 223. The optical detection assembly 4 is mounted on the bottom plate 5 through a mounting support plate.

[0111] In this embodiment, the laser light source includes two, a first laser 40 and a second laser 41; the lateral detectors include two, a first lateral detector 42 and a second lateral detector 43. The transmission optical path 44 includes a first reflector 440, a first dichroic mirror 441 and a focusing lens 442, and the optical detection assembly 4 also includes a second dichroic mirror 45, a first filter 46 and a second filter 47.

[0112] The laser light emitted by the first laser 40 is reflected by the first reflector 440 and then transmitted through the first dichroic mirror 441. The laser light emitted by the second laser 41 is reflected by the first dichroic mirror 441 and merged with the laser light of the first laser 40. The laser light is focused by the focusing lens 442 onto the detection pipe section 223 to irradiate the sample droplets to be detected. The laser light after passing through the sample droplets to be detected continues to propagate forward to reach the forward detector 49.

[0113] After being irradiated by two lasers, the sample droplets to be tested are excited to produce two kinds of fluorescence, one of which is reflected by the second dichroic mirror 45 and reaches the first lateral detector 42 after passing through the first filter 46; the other is transmitted through the second dichroic mirror 45 and reaches the second lateral detector 43 after passing through the second filter 47.

[0114] The two lasers emit lasers of different wavelengths and are combined with two lateral detectors to achieve dual fluorescence signal detection, which can improve sample utilization and is even more significant for precious samples to be tested.

[0115] Among them, the lateral detector collects the fluorescence signal (lateral signal) generated by the excitation of the droplets of the sample to be tested, and the forward detector 49 collects the laser signal (forward signal) after the droplets of the sample to be tested on the detection pipeline section 223. The combination of the forward signal and the lateral signal is more conducive to the subsequent data processing. The forward signal directly characterizes the physical form of the droplets, and the fluorescence signal is the fluorescence after excitation, which cannot characterize the form of the droplets. In the subsequent fault maintenance process, fault judgment is carried out, and the maintenance personnel can make judgments by observing the form of the droplets in the forward direction. In addition, the fluorescence signal is greatly affected by amplification. If the amplification is good, the fluorescence signal is relatively uniform, and if the amplification is not good, the signal is relatively scattered. The forward signal is mainly affected by the physical form of the droplets. The droplets can be quickly judged by the forward signal to perform algorithm processing of the fluorescence positive and negative. It is easier to achieve in the peak search algorithm processing process, and the probability of misreading or leakage is low, and the accuracy is high.

[0116] Furthermore, the number of laser light sources and lateral detectors can be further expanded on the basis of the above to achieve more types of fluorescence signal detection.

[0117] The working process of the entire instrument is: first, the sample droplets to be tested are stored in the well plate, and then the well plate is placed in the droplet reader, and then the sample in the well plate is sucked by the three-dimensional mobile robot 30, and transported to the detection chip 22 through the liquid delivery system 2, and with the help of the shearing effect of the detection oil, the sample droplets to be tested are arranged in sequence through the detection pipeline section 223, and the optical detection component 4 is used to realize the fluorescence detection of each droplet.

[0118] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A droplet reader, characterized in that: include: Liquid storage components, liquid delivery system, sample loading components and optical detection components; The liquid storage component is used to provide test oil and collect waste oil, and the sample loading component is used to absorb the test sample droplets placed in the droplet reader, and transport the test sample droplets through the liquid delivery system so that the test sample droplets are arranged in sequence through the detection position of the optical detection component, so as to perform fluorescence detection on the test sample droplets; The liquid storage assembly comprises a liquid storage base, a liquid tank box slidably arranged on the liquid storage base, and at least two liquid storage tanks arranged in the liquid tank box; the at least two liquid storage tanks comprise at least one detection oil tank and one waste oil tank; The sample loading assembly comprises a three-dimensional mobile mechanical arm, a sample storage device and a sample injection needle arranged on the three-dimensional mobile mechanical arm; the sample storage device is used to store droplets of samples to be tested; The liquid delivery system includes an oil delivery pipeline connected to the detection oil tank, an oil pump arranged on the oil delivery pipeline, a detection chip connected to the output end of the oil delivery pipeline through an oil inlet, a sample pump, a sample delivery pipeline connected between the sample pump and the sample inlet of the detection chip, a reversing valve arranged on the sample delivery pipeline, a sample suction pipeline connected between the reversing valve and the sample injection needle, a waste oil pipeline connected between the total outlet of the detection chip and the waste oil tank, and a solenoid valve arranged on the waste oil pipeline; The droplet reader also includes a bottom plate, and the liquid storage component, liquid delivery system, sample loading component and optical detection component are all arranged on the bottom plate; The liquid storage base is fixedly connected to the bottom plate, and the liquid storage tank comprises a tank body, a tank opening arranged on the top of the tank body, a joint pipe arranged on the tank opening, a joint converter with a lower end inserted into the joint pipe and an upper end extending out, and a tank cover threadedly matched with the joint pipe for fixing the lower end of the joint converter in the joint pipe; The joint converter is provided with a plurality of channels for connecting the inside of the tank with the outside; The channel includes a horizontal channel and a vertical channel that are interconnected. The horizontal channel forms an external pipeline interface on the side of the upper end of the joint converter, and the vertical channel forms an internal pipeline interface on the lower end surface of the joint converter.

2. The droplet reader according to claim 1, characterized in that The reversing valve comprises at least a first port, a second port and a third port, and can be switched between a first state and a second state, wherein the first state is: the first port and the second port are connected, and the second port and the third port are disconnected; and the second state is: the second port and the third port are connected, and the first port and the second port are disconnected; The second port is connected to the sample pump through the sample delivery pipeline, the third port is connected to the sample inlet of the detection chip through the sample delivery pipeline, and the first port is connected to the sample injection needle through the sample suction pipeline.

3. The droplet reader according to claim 2, characterized in that The detection chip includes two oil inlets, and a cross-shaped microfluidic structure is provided inside the detection chip. The microfluidic structure forms the sample inlet, two oil inlets and a total outlet on four sides of the detection chip, respectively. The two oil inlets are symmetrically distributed on both sides of the sample inlet.

4. The droplet reader according to claim 1, characterized in that A through hole is provided in the middle of the tank cover, and an annular flange is provided on the inner edge of the upper end thereof; An annular baffle is provided on the outer periphery of the joint converter, and the outer diameter of the annular baffle is smaller than the diameter of the through hole and larger than the inner diameter of the annular flange; The joint converter is inserted into the joint pipe, and after the tank cover is threadedly connected to the joint pipe, the annular flange presses against the upper surface of the annular baffle.

5. The droplet reader according to claim 1, characterized in that: The three-dimensional mobile mechanical arm includes an X-axis motion component arranged on the base plate, a Y-axis motion component arranged on the X-axis motion component, and a Z-axis motion component arranged on the Y-axis motion component; The Z-axis motion assembly includes a Z-axis mounting plate arranged on the Y-axis motion assembly, a Z-axis motor arranged on the Z-axis mounting plate, a Z-axis lead screw drivingly connected to the Z-axis motor, and a Z-axis sleeve threadedly matched with the Z-axis lead screw; The injection needle is connected to the Z-axis sliding sleeve through a buffer connection block.

6. The droplet reader according to claim 5, characterized in that The buffer connection block is provided with a threaded hole, the upper part of the Z-axis sliding sleeve is provided with a boss, the boss is provided with a through hole, a screw with a diameter smaller than the through hole is inserted into the through hole, the lower part of the screw is fixedly connected to the threaded hole, and the upper end of the screw is provided with a nut with a diameter larger than the through hole; a spring is sleeved on the Z-axis sliding sleeve, the upper end of the spring is in contact with the bottom surface of the boss, and the lower end of the spring is in contact with the buffer connection block; The buffer connection block is provided with a through hole having a diameter larger than that of the Z-axis screw rod for the Z-axis screw rod to pass through, and the upper portion of the buffer connection block is also provided with a receiving groove for receiving the Z-axis sliding sleeve.

7. The droplet reader according to claim 3, characterized in that: A detection pipeline section is connected between the total outlet of the detection chip and the waste liquid pipeline, and the detection pipeline section is located at the detection position of the optical detection component; The optical detection component includes at least two laser light sources, a transmission light path for transmitting light emitted by the at least two laser light sources to the sample droplets to be tested on the detection pipeline section, at least two lateral detectors for collecting fluorescence generated by the sample droplets to be tested on the detection pipeline section, and a forward detector for collecting laser light after passing through the sample droplets to be tested on the detection pipeline section.

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