An automatic nucleic acid extraction instrument for colorectal cancer screening

Abstract

The invention discloses an automatic nucleic acid extractor for colorectal cancer screening, wherein a mounting groove is arranged on a side wall of a shell of the extractor, a second placement box is slidably connected in the mounting groove, a chassis is slidably arranged inside the shell of the extractor, and a first placement box is detachably mounted on the chassis; an air inlet device is arranged at the bottom of the shell of the extractor, a fan, a filter and a heating wire are arranged in the air inlet device, and an air outlet device is arranged at the top of the shell of the extractor; the sample is replaced by driving the chassis to slide out when the chamber door is opened, and various reagents are replaced by opening the second placement box from the side to avoid pollution of the environment in the chamber caused by manual replacement, the temperature of the air flow is controlled by the heating wire in the air inlet device, the air flow with the set temperature passes through the chamber quickly from bottom to top, so as to realize rapid control of the temperature, and the chassis located directly above the air inlet device disperses the air flow to the side wall, so as to avoid the air flow facing the sample and the reagent, so as to make the temperature in the shell of the extractor more uniform.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an automatic nucleic acid extraction instrument for colorectal cancer screening. Background Art

[0002] The nucleic acid extraction instruments used in the process of colorectal cancer screening in the prior art still have some defects:

[0003] 1. The automatic nucleic acid extractor in the prior art requires various extractants, washing solutions and eluents in addition to the samples to be extracted, and generates a lot of waste liquid. Before extraction, the samples and various reagents need to be placed in the nucleic acid extractor in advance. When extracting multiple batches of samples, it is necessary not only to open the door to replace the samples, but also to replenish various reagents and discharge waste liquid. These replacement operations require opening the door, and manual operations in the nucleic acid extractor also pollute the environment in the chamber, affecting the test results.

[0004] 2. In addition, the temperature in the chamber needs to be controlled during the extraction of nucleic acid. Different temperatures are required at different stages. Therefore, temperature control of the nucleic acid extractor is extremely important. Opening the chamber door to replace samples and replenish reagents will also affect the temperature in the chamber. The existing temperature control system has a slow temperature adjustment speed and can easily cause local temperature unevenness.

[0005] 3. At the same time, the parts of the nucleic acid extractor that house samples and reagents cannot be disassembled separately, making internal cleaning and disinfection less convenient.

[0006] In view of the above problems, the inventors proposed an automatic nucleic acid extraction instrument for colorectal cancer screening to solve the above problems. Summary of the invention

[0007] In order to solve the problems mentioned in the above background technology, the purpose of the present invention is to provide an automatic nucleic acid extraction instrument for colorectal cancer screening.

[0008] An automatic nucleic acid extractor for colorectal cancer screening comprises an extractor housing and a mixed magnetic unit for extracting and purifying nucleic acids, wherein the mixed magnetic unit is mounted on the top wall of the extractor housing, an opening is provided on one side of the extractor housing, and a compartment door is provided on the inner wall of the opening:

[0009] The side wall of the extractor housing is provided with an installation groove, a second placement box is slidably connected in the installation groove, a slide groove is provided in the part of the installation groove in the extractor housing, the second placement box is used to place containers containing magnetic bead binding liquid, magnetic bead washing liquid, magnetic bead elution liquid and waste liquid, a chassis is slidably provided inside the extractor housing, a first placement box is detachably installed on the chassis, and the first placement box is used to place a container containing a sample to be extracted;

[0010] An air inlet device is arranged at the bottom of the extractor shell, and a fan, a filter and a heating wire are arranged in the air inlet device. When the compartment door is closed, the chassis is located above the air inlet device, and the airflow generated by the air inlet device passes through the side of the chassis. An air outlet device is arranged at the top of the extractor shell, and a filter is arranged in the air outlet device.

[0011] Preferably, a return-shaped sealing ring is fixedly mounted on the outer wall of the door, and the outer wall of the return-shaped sealing ring is in movable contact with the inner wall of the opening;

[0012] A U-shaped equipment frame is fixedly mounted on the outer wall of the extractor housing, and an opening and closing mechanism for controlling the automatic opening and closing of the chamber door is provided on the extractor housing;

[0013] An automatic exit mechanism for controlling the chassis to automatically enter and exit the warehouse is arranged in the U-shaped equipment frame, and a limiting mechanism for fixing the first placement box is arranged on the chassis.

[0014] Preferably, the opening and closing mechanism includes a rotating shaft, which passes through the warehouse door and is fixedly connected to the warehouse door, and the end of the rotating shaft is rotatably connected to the inner wall of the opening. A first rotating rod is rotatably installed on one side of the extractor shell, and one end of the first rotating rod and one end of the rotating shaft are fixedly installed with a first bevel gear, and the two first bevel gears are meshed with each other.

[0015] Preferably, a drive motor is fixedly provided on one side of the extractor housing away from the opening, and one end of the first rotating rod away from the first bevel gear is fixedly connected to a drive output end of the drive motor.

[0016] Preferably, an L-shaped support frame is fixedly mounted on the outer wall of the driving motor, and one end of the L-shaped support frame is fixedly connected to a side of the extractor housing away from the opening.

[0017] Preferably, the automatic warehouse exit mechanism includes four rotating shafts, one end of the four rotating shafts is rotatably mounted on the top wall of the U-shaped equipment frame, the other ends of the four rotating shafts are fixedly mounted with transmission wheels, a toothed belt is transmission-installed between two adjacent transmission wheels, toothed plates are fixedly mounted on both sides of the chassis, and one toothed belt is meshed with a toothed plate.

[0018] Preferably, the side wall of the extractor shell is provided with two guide grooves, one end of each of the guide grooves is slidably mounted with a guide block, the opposite sides of the two guide blocks are fixedly mounted with an L-shaped connecting frame, and one end of the two L-shaped connecting frames is fixedly connected to the upper surface of the chassis.

[0019] Preferably, a second rotating rod is rotatably installed on the inner wall of the U-shaped equipment frame, and a first synchronous wheel is fixedly installed on one end of the second rotating rod and one end of one of the rotating shafts, and a first synchronous belt is installed for transmission between the two first synchronous wheels; a transmission rod is also rotatably installed on the inner wall of the U-shaped equipment frame, and a second synchronous wheel is fixedly installed on one end of the second rotating rod and one end of the transmission rod, and a second synchronous belt is installed for transmission between the two second synchronous wheels; a transmission gear is fixedly installed on the other end of the transmission rod and one end of another rotating shaft, and the two transmission gears are meshed with each other.

[0020] Preferably, a second bevel gear is fixedly mounted on one end of the first rotating rod close to the driving motor and one end of the second rotating rod away from the first synchronous wheel, and the two second bevel gears are meshed with each other.

[0021] Preferably, the limiting mechanism includes four flip plates, one end of the four flip plates is fixedly installed with a card block, the first placement box is provided with card slots all around, the card block is in movably contact with the inner wall of the card slot, four third rotating rods are rotatably installed inside the chassis, one end of the four third rotating rods is fixedly installed with a worm gear, four worms are rotatably installed inside the chassis, one worm wheel is meshingly connected with a worm, one end of the four worms is fixedly installed with a connecting seat, and one end of the flip plate away from the card block is fixedly connected to the outer wall of a connecting seat.

[0022] Preferably, two fourth rotating rods are rotatably installed on the upper surface of the chassis, one end of the two fourth rotating rods is fixedly installed with a knob, the other end of the two fourth rotating rods is fixedly installed with a third bevel gear, the other end of the four third rotating rods is fixedly installed with a fourth bevel gear, and one third bevel gear is meshingly connected with two adjacent fourth bevel gears.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. In the present invention, a first placement box containing samples is installed on a slidably connected chassis, and a second placement box containing containers for magnetic bead binding solution, magnetic bead washing solution, magnetic bead elution solution and waste liquid is slidably connected in a mounting groove on the side wall of the extractor shell. The sliding of the second placement box is achieved by setting a slide groove. When the chamber door is opened, the chassis is driven to slide out, which is convenient for replacing samples. When various reagents need to be supplemented or the waste liquid is full, the second placement box can be opened from the side for replacement. The replacement of samples and reagents does not interfere with each other, thereby minimizing the impact of manual replacement on the environment in the chamber.

[0025] 2. In the present invention, an air inlet device is arranged at the bottom of the extractor shell, and an air outlet device is arranged at the top of the extractor shell. The air flow temperature is controlled by a heating wire in the air inlet device, and the air flow with the set temperature quickly passes through the bin from bottom to top to achieve rapid temperature control. When the bin door is closed, the chassis is located directly above the air inlet device, and the air flow in the air inlet device is dispersed to the side wall of the extractor shell to avoid the air flow directly facing the sample and the reagent, so that the temperature in the extractor shell is more uniform. When the bin door is opened, the chassis is moved away, and the air flow is increased at this time, which can be used to remove the residual solution on the mixing magnetic suction unit.

[0026] 3. In the present invention, the automatic opening and closing of the chamber door is controlled by the opening and closing mechanism, and the automatic in and out of the chamber of the chassis and the first placement box is controlled by the automatic chamber exit mechanism, so that the extraction personnel can place the sample in the first placement box and carry out the next step of nucleic acid extraction, thereby conveniently realizing the automatic opening of the chamber door and the automatic exit of the first placement box, thereby effectively reducing the convenience of opening and closing the chamber door, while reducing the work intensity of the extraction personnel, and reducing the probability of bacterial infection in the shell of the extraction instrument;

[0027] 4. In the present invention, by driving the flip plate to flip, the flip plate disengages the card block from the card slot, and releases the limit on the first placement box, thereby conveniently realizing the disassembly of the first placement box, and then the second placement box is disassembled by taking out the second placement box from the slide slot. Compared with the existing technology that cannot be disassembled, the convenience of cleaning and disinfecting the first placement box is effectively improved, and the probability of infection in the extractor shell is further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of the external structure of the shell of the extractor of the present invention.

[0030] Figure 2 It is a schematic diagram of the open state of the warehouse door of the present invention.

[0031] Figure 3 It is a schematic diagram of the state of the warehouse door being opened and the chassis being out of the warehouse according to the present invention.

[0032] Figure 4 It is a connection diagram of the warehouse door, U-shaped equipment frame, opening and closing mechanism and automatic warehouse exit mechanism of the present invention.

[0033] Figure 5 It is a schematic diagram of the connection between the warehouse door, chassis, opening and closing mechanism and automatic warehouse exit mechanism of the present invention.

[0034] Figure 6 For the present invention Figure 5 A magnified schematic diagram of part A in FIG.

[0035] Figure 7 For the present invention Figure 5 An enlarged schematic diagram of part B in FIG.

[0036] Figure 8 For the present invention Figure 5 Enlarged schematic diagram of part C in FIG.

[0037] Fig. 9 It is a schematic diagram of the connection between the limiting mechanism of the present invention, the chassis and the first placement box.

[0038] Fig.10 It is a structural schematic diagram of the limiting mechanism of the present invention.

[0039] In the figure: 1. Extractor housing; 11. Opening; 12. Door; 13. Reciprocating seal ring; 14. Chassis; 15. First placement box; 16. U-shaped equipment frame; 17. Mixing magnetic suction unit; 2. Opening and closing mechanism; 21. Rotating shaft; 22. First rotating rod; 23. First bevel gear; 24. Driving motor; 25. L-shaped support frame; 3. Automatic warehouse exit mechanism; 31. Rotating shaft; 32. Transmission wheel; 33. Toothed belt; 34. Toothed plate; 35. Guide groove; 36. Guide block; 37. L-shaped connecting frame; 38. Second rotating rod Rod; 39, first synchronous wheel; 4, first synchronous belt; 41, transmission rod; 42, second synchronous wheel; 43, second synchronous belt; 44, transmission gear; 45, second bevel gear; 5, limiting mechanism; 51, flip plate; 52, block; 53, slot; 54, third rotating rod; 55, worm gear; 56, worm; 57, connecting seat; 58, fourth rotating rod; 59, knob; 6, third bevel gear; 61, fourth bevel gear; 101, slide slot; 91, second placement box; 81, air inlet device; 82, air outlet device. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0041] Example: Figure 1-10 As shown, the present invention provides an automatic nucleic acid extractor for colorectal cancer screening, comprising an extractor housing 1 and a mixed magnetic unit 17 for extracting and purifying nucleic acids, wherein the mixed magnetic unit 17 is mounted on the top wall of the extractor housing 1, an opening 11 is provided on one side of the extractor housing 1, and a compartment door 12 is provided on the inner wall of the opening 11:

[0042] A mounting groove is provided on the side wall of the extractor housing 1, and a second placement box 91 is slidably connected in the mounting groove. A slide groove 101 is provided in the portion of the mounting groove in the extractor housing 1. The second placement box 91 is used to place containers containing magnetic bead binding liquid, magnetic bead washing liquid, magnetic bead elution liquid and waste liquid. A chassis 14 is slidably provided inside the extractor housing 1, and a first placement box 15 is detachably installed on the chassis 14. The first placement box 15 is used to place a container containing a sample to be extracted;

[0043] An air inlet device 81 is provided at the bottom of the extractor shell 1, and a fan, a filter and a heating wire are provided in the air inlet device 81. When the compartment door 12 is closed, the chassis 14 is located above the air inlet device 81, and the airflow generated by the air inlet device 81 passes through the side of the chassis 14. An air outlet device 82 is provided at the top of the extractor shell 1, and a filter is provided in the air outlet device 82.

[0044] It is further provided that a return-shaped sealing ring 13 is fixedly mounted on the outer wall of the door 12, and the outer wall of the return-shaped sealing ring 13 is in movable contact with the inner wall of the opening 11;

[0045] A U-shaped device frame 16 is fixedly mounted on the outer wall of the extractor housing 1, and an opening and closing mechanism 2 for controlling the automatic opening and closing of the chamber door 12 is provided on the extractor housing 1;

[0046] An automatic exit mechanism 3 for controlling the chassis 14 to automatically enter and exit the bin is disposed in the U-shaped equipment frame 16 , and a limiting mechanism 5 for fixing the first placement box 15 is disposed on the chassis 14 .

[0047] By adopting the above technical scheme, by setting the return-shaped sealing ring 13, the return-shaped sealing ring 13 can improve the sealing between the chamber door 12 and the opening 11, by setting the first placement box 15, it is convenient to place the sample to be extracted, and the mixing magnetic unit 17 performs nucleic acid extraction operation on the sample in the extractor shell 1 (this is the prior art and will not be repeated here), by setting the opening and closing mechanism 2 and the automatic warehouse exit mechanism 3, the opening and closing mechanism 2 can realize the automatic opening and closing of the chamber door 12, and the automatic warehouse exit mechanism 3 can realize the automatic entry and exit of the sample through the chassis 14 and the first placement box 15, thereby reducing the work intensity of the extraction personnel and the probability of bacterial infection in the extraction instrument shell 1. By setting the limiting mechanism 5, the limiting mechanism 5 can fix the first placement box 15 on the chassis 14, and at the same time, the first placement box 15 can be released from the limit, so that the first placement box 15 can be detachable, thereby facilitating the extraction personnel to clean and disinfect the first placement box 15.

[0048] The opening and closing mechanism 2 includes a rotating shaft 21, which passes through the compartment door 12 and is fixedly connected to the compartment door 12. The end of the rotating shaft 21 is rotatably connected to the inner wall of the opening 11. A first rotating rod 22 is rotatably installed on one side of the extractor housing 1. One end of the first rotating rod 22 and one end of the rotating shaft 21 are fixedly installed with a first bevel gear 23, and the two first bevel gears 23 are meshed with each other.

[0049] By adopting the above technical solution, by driving the first rotating rod 22 to rotate, the first rotating rod 22 can rotate the rotating shaft 21 through the two first bevel gears 23, and the rotating shaft 21 can make the warehouse door 12 and the return sealing ring 13 flip around the axis of the rotating shaft 21 as the center of the circle, thereby realizing the automatic opening and closing of the warehouse door 12.

[0050] A driving motor 24 is fixedly provided on one side of the extractor housing 1 away from the opening 11 , and one end of the first rotating rod 22 away from the first bevel gear 23 is fixedly connected to a driving output end of the driving motor 24 .

[0051] By adopting the above technical solution, by turning on the drive motor 24 , the drive shaft of the drive motor 24 can rotate the first rotating rod 22 .

[0052] An L-shaped support frame 25 is fixedly mounted on the outer wall of the driving motor 24 , and one end of the L-shaped support frame 25 is fixedly connected to a side of the extractor housing 1 away from the opening 11 .

[0053] By adopting the above technical solution and providing the L-shaped support frame 25 , the L-shaped support frame 25 can support and fix the driving motor 24 , thereby improving the stability of the driving motor 24 .

[0054] The automatic warehouse discharge mechanism 3 includes four rotating shafts 31, one end of the four rotating shafts 31 is rotatably installed on the top wall of the U-shaped equipment frame 16, and the other ends of the four rotating shafts 31 are fixedly installed with transmission wheels 32, and a toothed belt 33 is installed between two adjacent transmission wheels 32. Toothed plates 34 are fixedly installed on both sides of the chassis 14, and a toothed belt 33 and a toothed plate 34 are meshed and connected.

[0055] By adopting the above technical solution, the rotating shaft 31 is driven to rotate, and the rotating shaft 31 transmits the toothed belt 33 through the transmission wheel 32. The toothed belt 33 drives the toothed plate 34 to move horizontally, and the toothed plate 34 moves the chassis 14 horizontally, thereby realizing the automatic entry and exit of the chassis 14 and the first placement box 15.

[0056] Two guide grooves 35 are provided on the side wall of the extractor housing 1 , and a guide block 36 is slidably installed at one end of the two guide grooves 35 , and an L-shaped connecting frame 37 is fixedly installed on the opposite side of the two guide blocks 36 , and one end of the two L-shaped connecting frames 37 is fixedly connected to the upper surface of the chassis 14 .

[0057] By adopting the above technical solution, by setting the guide groove 35, the guide block 36 and the L-shaped connecting frame 37, the guide block 36 can slide horizontally along the inner wall of the guide groove 35, and the L-shaped connecting frame 37 can keep the chassis 14 moving in the horizontal direction, while improving the stability of the chassis 14.

[0058] A second rotating rod 38 is rotatably installed on the inner wall of the U-shaped equipment frame 16, and a first synchronous wheel 39 is fixedly installed on one end of the second rotating rod 38 and one end of one of the rotating shafts 31, and a first synchronous belt 4 is installed for transmission between the two first synchronous wheels 39. A transmission rod 41 is also rotatably installed on the inner wall of the U-shaped equipment frame 16, and a second synchronous wheel 42 is fixedly installed on one end of the second rotating rod 38 and one end of the transmission rod 41, and a second synchronous belt 43 is installed for transmission between the two second synchronous wheels 42, and a transmission gear 44 is fixedly installed on the other end of the transmission rod 41 and one end of the other rotating shaft 31, and the two transmission gears 44 are meshed with each other.

[0059] By adopting the above technical scheme, by driving the second rotating rod 38 to rotate, the second rotating rod 38 causes a rotating shaft 31 to rotate synchronously in the same direction through two first synchronous wheels 39 and the first synchronous belt 4, the second rotating rod 38 causes the transmission rod 41 to rotate synchronously in the same direction through two second synchronous wheels 42 and the second synchronous belt 43, and the transmission rod 41 causes another rotating shaft 31 to rotate synchronously in the opposite direction through two transmission gears 44, so that the rotating shafts 31 on both sides of the extractor housing 1 are in a synchronous reverse rotation state, and then the two toothed belts 33 are in a synchronous reverse transmission state, and the synchronous reverse transmission of the two toothed belts 33 keeps the two tooth plates 34 moving horizontally in the same direction.

[0060] A second bevel gear 45 is fixedly mounted on one end of the first rotating rod 22 close to the driving motor 24 and one end of the second rotating rod 38 away from the first synchronous wheel 39 , and the two second bevel gears 45 are meshed with each other.

[0061] By adopting the above technical solution, when the first rotating rod 22 rotates, the first rotating rod 22 causes the second rotating rod 38 to rotate through the two second bevel gears 45 .

[0062] The limiting mechanism 5 includes four flip plates 51, one end of each of the four flip plates 51 is fixedly installed with a card block 52, the first placement box 15 is provided with a card slot 53 on all sides, the card block 52 is in movably contact with the inner wall of the card slot 53, four third rotating rods 54 are rotatably installed inside the chassis 14, one end of each of the four third rotating rods 54 is fixedly installed with a worm gear 55, four worm gears 56 are rotatably installed inside the chassis 14, a worm gear 55 is meshingly connected with a worm gear 56, one end of each of the four worm gears 56 is fixedly installed with a connecting seat 57, and one end of a flip plate 51 away from the card block 52 is fixedly connected to the outer wall of a connecting seat 57.

[0063] By adopting the above technical solution, by providing the flip plate 51, the block 52 and the slot 53, when the flip plate 51 flips, the flip plate 51 can make the block 52 enter the slot 53 or disengage from the slot 53. After the block 52 enters the slot 53, the block 52 limits the first placement box 15 through the slot 53, so that the first placement box 15 is fixed on the chassis 14. By driving the third rotating rod 54 to rotate, the third rotating rod 54 rotates the worm gear 55, the worm gear 55 drives the worm 56 to rotate, and the worm 56 rotates the flip plate 51 through the connecting seat 57 with the axis of the connecting seat 57 as the center of the circle.

[0064] Two fourth rotating rods 58 are rotatably installed on the upper surface of the chassis 14, and a knob 59 is fixedly installed at one end of the two fourth rotating rods 58, and a third bevel gear 6 is fixedly installed at the other end of the two fourth rotating rods 58. A fourth bevel gear 61 is fixedly installed at the other end of the four third rotating rods 54, and one third bevel gear 6 is meshedly connected with two adjacent fourth bevel gears 61.

[0065] By adopting the above technical solution, by rotating the knob 59, the knob 59 can rotate the fourth rotating rod 58, and the fourth rotating rod 58 causes the two third rotating rods 54 to rotate synchronously in the opposite direction through a third bevel gear 6 and two fourth bevel gears 61, thereby causing the two adjacent flip plates 51 to flip synchronously in the opposite direction or flip synchronously towards each other.

[0066] Working principle: When nucleic acid extraction is required for a sample, the extractor first turns on the drive motor 24. The drive shaft of the drive motor 24 rotates the first rotating rod 22. The first rotating rod 22 rotates the rotating shaft 21 through two first bevel gears 23. The rotating shaft 21 causes the chamber door 12 and the return seal ring 13 to turn around the axis of the rotating shaft 21. At this time, the chamber door 12 gradually turns over and opens.

[0067] At the same time, the first rotating rod 22 rotates the second rotating rod 38 through the two second bevel gears 45, and the second rotating rod 38 rotates the corresponding rotating shaft 31 synchronously in the same direction through the two first synchronous wheels 39 and the first synchronous belt 4. At the same time, the second rotating rod 38 rotates the transmission rod 41 synchronously in the same direction through the two second synchronous wheels 42 and the second synchronous belt 43, and the transmission rod 41 rotates the other rotating shaft 31 synchronously in the opposite direction through the two transmission gears 44. At this time, the two rotating shafts 31 on both sides of the extractor housing 1 are in a synchronous reverse rotation state, and the four rotating shafts 31 cause the two toothed belts 33 to be in a synchronous reverse transmission state through the corresponding two transmission wheels 32. The synchronous reverse transmission of the two toothed belts 33 causes the chassis 14 and the first placement box 15 to move horizontally toward the outside of the extractor housing 1 through the two tooth plates 34, thereby conveniently realizing the automatic opening of the warehouse door 12 and the automatic exit of the first placement box 15, thereby effectively reducing the convenience of opening and closing the warehouse door 12, while reducing the work intensity of the extraction personnel, and reducing the probability of bacterial infection in the extractor housing 1.

[0068] After the first placement box 15 is out of the chamber, the extraction personnel place the sample to be extracted nucleic acid in the first placement box 15, and then start the drive motor 24 to make the drive shaft of the drive motor 24 rotate in the opposite direction, and the chamber door 12 flips in the opposite direction and gradually closes. During this process, the chassis 14 and the first placement box 15 move horizontally toward the inside of the extraction instrument housing 1 and return to the initial state;

[0069] When it is necessary to clean and disinfect the first placement box 15, the extraction personnel turn the two knobs 59 respectively (the chassis 14 and the first placement box 15 are in the out-of-warehouse state), and the two knobs 59 rotate the two fourth rotating rods 58. The two fourth rotating rods 58 cause the two adjacent third rotating rods 54 to rotate synchronously in the opposite direction through a corresponding third bevel gear 6 and two fourth bevel gears 61. At this time, the four third rotating rods 54 cause the two adjacent flip plates 51 to rotate synchronously in the opposite direction through the corresponding worm gear 55, worm 56 rotation and connecting seat 57. At this time, the four flip plates 51 cause the four card blocks 52 to disengage from the corresponding card slots 53, and then the extraction personnel manually remove the first placement box 15 from the chassis 14, thereby conveniently realizing the disassembly of the first placement box 15. Compared with the existing technology that cannot be disassembled, it effectively improves the convenience of cleaning and disinfection of the first placement box 15, and further reduces the probability of infection in the extractor housing 1.

[0070] The specific automatic nucleic acid extraction process for colorectal cancer screening involved in this scheme can refer to the following case: a method for extracting DNA from human feces, the method comprising the following steps:

[0071] Step 1: Collection of stool samples:

[0072] After a person excretes feces, immediately collect 2-5g of feces sample and put it into a collection tube, which contains 10-15mL of feces preservation solution. Shake the collection tube to mix the feces sample and feces preservation solution thoroughly.

[0073] The stool retention solution comprises: 0.3-0.6M EDTA, 3-6M NaCl, 0.3-1.5M Tris;

[0074] Step 2: Transportation of stool samples:

[0075] Fecal samples collected by conventional logistics transportation under normal or low temperature conditions and arriving at the laboratory for processing within 3 days;

[0076] Step 3: Sampling of fecal samples:

[0077] After the stool sample arrives at the laboratory, mix it thoroughly, pipette 800μL-2000μL of the stool sample into a centrifuge tube, and mix it again;

[0078] Step 4: DNA extraction from stool samples:

[0079] (1) Cell precipitation

[0080] Centrifuge the centrifuge tube containing the stool sample at 10,000-13,000 rpm for 2-5 minutes, retain the precipitate, and remove the supernatant;

[0081] (2) Cell lysis releases DNA

[0082] Add 800-1000 μL of fecal lysate to the centrifuge tube in step (1), mix thoroughly with the precipitate, and incubate at 68-75°C for 10 minutes;

[0083] The feces lysis solution comprises: 0.5-1.2% (m / v) CTAB, 0.8-1.4M NaCl, 0.08-0.12% (m / v) Tris, 10-15mM EDTA, and 0.1-0.2M isomercaptoethanol;

[0084] (3) Precipitation of impurities

[0085] Centrifuge the centrifuge tube in step (2) at 10,000-13,000 rpm for 1 minute, transfer the supernatant to a new centrifuge tube, and remove precipitated impurities;

[0086] (4) Removal of impurities and purification of DNA

[0087] Add 500-600 μL of impurity separation liquid to the supernatant obtained in step (3), mix thoroughly for 5-10 minutes, and then centrifuge at 10000-13000 rpm for 5-10 minutes. The liquid is separated into three layers. Transfer the upper supernatant to a new centrifuge tube to remove the precipitated impurities in the middle and lower layers. In this step, the transfer of the upper supernatant must be performed in a biosafety cabinet;

[0088] The impurity separation liquid comprises: chloroform;

[0089] (5) Magnetic beads bind DNA

[0090] Add 600-800 μL of magnetic bead binding solution and 30-100 μL of magnetic beads to the supernatant obtained in step (4), and incubate at room temperature for 15-30 minutes to obtain a magnetic bead mixture;

[0091] The magnetic bead binding solution comprises: isopropanol;

[0092] (6) Magnetic bead washing and DNA elution

[0093] Place the magnetic bead mixture obtained in step (5) on a magnetic rack for 3-10 minutes. After the magnetic beads are completely adsorbed, wash them twice with a magnetic bead washing solution. Add 100-200 μL of magnetic bead elution solution, elute at room temperature for 10 minutes, and place on a magnetic rack. After the magnetic beads are adsorbed, pipette the elution solution into a new centrifuge tube. The elution solution is the DNA-containing solution.

[0094] The magnetic bead washing solution comprises: 75% to 80% ethanol by volume;

[0095] The magnetic bead elution solution comprises: nuclease-free water.

[0096] Specifically, the automatic nucleic acid extractor for colorectal cancer screening designed in the present invention can be used in step (4) removing impurities and purifying DNA, step (5) binding DNA with magnetic beads, and step (6) washing magnetic beads and eluting DNA.

[0097] Steps that require centrifugation can be performed in a centrifuge device outside the extractor, or a centrifuge structure can be set on the chassis 14. Steps that require vibration can add a vibration function to the mixing magnetic unit 17. The mixing magnetic unit 17 is at least a three-axis moving structure, and the vibration structure is set on the upper and lower moving axes.

[0098] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An automatic nucleic acid extractor for colorectal cancer screening, comprising an extractor housing (1) and a hybrid magnetic unit (17) for extracting and purifying nucleic acids, wherein the hybrid magnetic unit (17) is mounted on the top wall of the extractor housing (1), an opening (11) is provided on one side of the extractor housing (1), and a compartment door (12) is provided on the inner wall of the opening (11), characterized in that: The extractor housing (1) is provided with a mounting groove on the side wall, a second placement box (91) is slidably connected in the mounting groove, a slide groove (101) is provided in the portion of the mounting groove in the extractor housing (1), the second placement box (91) is used to place containers containing magnetic bead binding liquid, magnetic bead washing liquid, magnetic bead elution liquid and waste liquid, the extractor housing (1) is slidably provided with a bottom plate (14), a first placement box (15) is detachably mounted on the bottom plate (14), and the first placement box (15) is used to place containers containing samples to be extracted; An air inlet device (81) is provided at the bottom of the extractor housing (1), and a fan, a filter and a heating wire are provided in the air inlet device (81); when the compartment door (12) is closed, the bottom plate (14) is located above the air inlet device (81), and the airflow generated by the air inlet device (81) passes through the side of the bottom plate (14); an air outlet device (82) is provided at the top of the extractor housing (1), and a filter is provided in the air outlet device (82); A return-shaped sealing ring (13) is fixedly mounted on the outer wall of the door (12), and the outer wall of the return-shaped sealing ring (13) is in movable contact with the inner wall of the opening (11); A U-shaped device frame (16) is fixedly mounted on the outer wall of the extractor housing (1), and an opening and closing mechanism (2) for controlling the automatic opening and closing of the chamber door (12) is provided on the extractor housing (1); An automatic exit mechanism (3) for controlling the chassis (14) to automatically enter and exit the bin is provided in the U-shaped equipment frame (16); a limiting mechanism (5) for fixing the first placement box (15) is provided on the chassis (14); The opening and closing mechanism (2) comprises a rotating shaft (21), the rotating shaft (21) passes through the compartment door (12) and is fixedly connected to the compartment door (12), the end of the rotating shaft (21) is rotatably connected to the inner wall of the opening (11), a first rotating rod (22) is rotatably mounted on one side of the extractor housing (1), one end of the first rotating rod (22) and one end of the rotating shaft (21) are both fixedly mounted with a first bevel gear (23), and the two first bevel gears (23) are meshed with each other; A drive motor (24) is fixedly provided on a side of the extractor housing (1) away from the opening (11), and an end of the first rotating rod (22) away from the first bevel gear (23) is fixedly connected to a drive output end of the drive motor (24); An L-shaped support frame (25) is fixedly mounted on the outer wall of the driving motor (24), and one end of the L-shaped support frame (25) is fixedly connected to a side of the extractor housing (1) away from the opening (11); The automatic warehouse discharging mechanism (3) comprises four rotating shafts (31), one end of the four rotating shafts (31) is rotatably mounted on the top wall of the U-shaped equipment frame (16), the other end of the four rotating shafts (31) is fixedly mounted with a transmission wheel (32), a toothed belt (33) is transmission-mounted between two adjacent transmission wheels (32), toothed plates (34) are fixedly mounted on both sides of the chassis (14), and one toothed belt (33) is meshingly connected with a toothed plate (34); A second rotating rod (38) is rotatably mounted on the inner wall of the U-shaped device frame (16); a first synchronous wheel (39) is fixedly mounted on one end of the second rotating rod (38) and one end of one of the rotating shafts (31); a first synchronous belt (4) is installed between the two first synchronous wheels (39); a transmission rod (41) is rotatably mounted on the inner wall of the U-shaped device frame (16); a second synchronous wheel (42) is fixedly mounted on one end of the second rotating rod (38) and one end of the transmission rod (41); a second synchronous belt (43) is installed between the two second synchronous wheels (42); a transmission gear (44) is fixedly mounted on the other end of the transmission rod (41) and one end of the other rotating shaft (31); the two transmission gears (44) are meshed with each other; A second bevel gear (45) is fixedly mounted on one end of the first rotating rod (22) close to the driving motor (24) and one end of the second rotating rod (38) away from the first synchronous wheel (39), and the two second bevel gears (45) are meshed with each other.

2. The automatic nucleic acid extraction instrument for colorectal cancer screening according to claim 1, characterized in that: The side wall of the extractor housing (1) is provided with two guide grooves (35), one end of each of the two guide grooves (35) is slidably mounted with a guide block (36), opposite sides of each of the two guide blocks (36) are fixedly mounted with an L-shaped connecting frame (37), and one end of each of the two L-shaped connecting frames (37) is fixedly connected to the upper surface of the chassis (14).

3. The automatic nucleic acid extraction instrument for colorectal cancer screening according to claim 1, characterized in that: The limiting mechanism (5) comprises four flip plates (51), one end of each of the four flip plates (51) is fixedly mounted with a clamping block (52), the first placement box (15) is provided with a clamping slot (53) on all sides, the clamping block (52) and the inner wall of the clamping slot (53) are in movable contact, four third rotating rods (54) are rotatably mounted inside the chassis (14), one end of each of the four third rotating rods (54) is fixedly mounted with a worm gear (55), four worm gears (56) are rotatably mounted inside the chassis (14), one of the worm gears (55) and a worm gear (56) are meshingly connected, one end of each of the four worm gears (56) is fixedly mounted with a connecting seat (57), and one end of each of the flip plates (51) away from the clamping block (52) is fixedly connected to the outer wall of a connecting seat (57).

4. The automatic nucleic acid extraction instrument for colorectal cancer screening according to claim 3, characterized in that: Two fourth rotating rods (58) are rotatably mounted on the upper surface of the chassis (14); a knob (59) is fixedly mounted on one end of each of the two fourth rotating rods (58); a third bevel gear (6) is fixedly mounted on the other end of each of the two fourth rotating rods (58); a fourth bevel gear (61) is fixedly mounted on the other end of each of the four third rotating rods (54); and one of the third bevel gears (6) is meshingly connected with two adjacent fourth bevel gears (61).

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