Preparation device and preparation method of sample to be detected for tea pesticide residue detection

Abstract

The invention discloses a to-be-detected sample preparation device for tea pesticide residue detection and a preparation method thereof.The to-be-detected sample preparation device comprises a machine table, a three-axis gantry moving frame, a feeding structure, an oscillation table, a pipe body transferring structure and a sample transferring frame and further comprises a multifunctional linkage structure, and the oscillation table comprises a main oscillation area and a plurality of auxiliary oscillation areas arranged on the periphery of the main oscillation area; the multifunctional linkage structure comprises a main driving piece arranged below the main oscillation area, an auxiliary driving piece is movably installed at the lower end of the auxiliary oscillation area and connected with the auxiliary oscillation area through a connecting piece, and the side, close to the main oscillation area, of the auxiliary oscillation area is connected with the main oscillation area through a linkage piece. The lower separation structure comprises a separation part arranged at the lower end of the main oscillation area, and a lower driving part is arranged at the lower end of the separation part. The full-automatic sample processing efficiency can be improved, and then the rear-end detection efficiency is improved.

Description

Technical Field

[0001] The present invention relates to tea detection, in particular to a device for preparing a sample for detecting tea pesticide residues and a preparation method thereof. Background Art

[0002] Improper use of chemical pesticides in the tea production process can easily lead to excessive pesticide residues. For companies, excessive pesticide residues will make it difficult for products to pass the corresponding testing agencies before they are put on the market. For consumers, excessive pesticide residues will harm their health and reduce their purchasing desire. For foreign export trade, comprehensive testing procedures are required before tea is produced.

[0003] Most traditional detection methods use a fully automatic sample pretreatment system during detection, which can shorten the entire pretreatment time and increase the recovery rate. However, if a fully automatic sample pretreatment system is used directly, the effect is very good for single samples. However, if it is used for simultaneous detection of multiple samples, product cross-contamination is very likely to occur. Therefore, the existing method uses a partitioned mixing method to perform different extractions, mixing, and precipitation in different areas to distinguish different samples. However, this is only applicable to equipment with larger models and more partitions. If it is used in a small device, it is difficult to separate the various areas. Samples of different weights and concentrations are difficult to distinguish, which leads to confusion between different samples. A part of the dispersed fluid is easy to diffuse and affect the surrounding control group, making it difficult to distinguish, which in turn easily affects the accuracy of the detection data.

[0004] Therefore, this case aims to provide a device and method for preparing test samples for tea pesticide residue detection, which can realize extraction between different areas in a small device, and can prepare a large number of samples from the same batch at the same time, and can also prepare samples from different batches at the same time, thereby improving the efficiency of fully automatic sample processing and thus improving the efficiency of back-end detection. Summary of the Invention

[0005] The present invention provides a device for preparing a sample for detecting pesticide residues in tea and a preparation method thereof, which can effectively solve the above problems.

[0006] The present invention is achieved in that: A device for preparing test samples for tea pesticide residue detection comprises: a machine platform, a three-axis gantry movable frame provided on the machine platform, a feeding structure for adding reactants to sample tubes provided on the three-axis gantry movable frame, an oscillating table for placing sample tubes provided at the upper end of the machine platform, a tube transfer structure provided on the other side of the feeding structure, a sample transfer rack provided on one side of the machine platform, the tube transfer structure transferring the mixed sample tubes to the sample transfer rack, and further comprising: A multifunctional linkage structure, wherein the oscillation table includes a main oscillation zone and a plurality of auxiliary oscillation zones arranged on the periphery of the main oscillation zone, the multifunctional linkage structure includes a main driving member arranged below the main oscillation zone, and an auxiliary driving member is movably installed at the lower end of the auxiliary oscillation zone, the auxiliary driving member is connected to the auxiliary oscillation zone through a connecting member, and the side of the auxiliary oscillation zone close to the main oscillation zone is connected to the main oscillation zone through a linkage member, when the same sample tube is placed in the main oscillation zone, the linkage member between the auxiliary oscillation zone and the main oscillation zone is separated, and the main driving member drives the main oscillation zone to rotate alone, and when different sample tubes are placed in the main oscillation zone and the auxiliary oscillation zone, the auxiliary oscillation zone and the main oscillation zone are linked by the linkage member, and the auxiliary driving member is separated from the auxiliary oscillation zone, so that the auxiliary oscillation zone is driven to rotate when the main oscillation zone rotates; The lower separation structure includes a separation member arranged at the lower end of the main oscillation zone, and a lower driving member is provided at the lower end of the separation member. When the main oscillation zone is separated from the auxiliary oscillation zone, the lower driving member pushes the separation member upward and separates it between the main oscillation zone and the auxiliary oscillation zone.

[0007] As a further improvement, the auxiliary driving component includes an auxiliary push rod motor arranged on the machine platform, and a matching seat is provided on the output end of the auxiliary push rod motor. The matching seat is a hexagonal structure, and the matching seat is fixed at the lower end of the auxiliary oscillation zone. Several card points are provided on the inner side of the matching seat.

[0008] As a further improvement, the inner side of the connecting piece is a hexagonal structure, and the mating seat is mated with the connecting piece after being pushed out by the auxiliary push rod motor. A number of protrusions are opened inside the connecting piece, and the card point and the protrusions are at the same height and staggered with each other.

[0009] As a further improvement, the linkage part includes several docking tubes arranged below the main oscillation zone, and a docking part is provided at the lower end of the auxiliary oscillation zone. When the auxiliary oscillation zone moves synchronously with the main oscillation zone, the docking part is pushed out and cooperates with the docking tube.

[0010] As a further improvement, the docking member includes a docking oil cylinder arranged on the outside of the connecting member, and a protective tube is sleeved on the output end of the docking oil cylinder, and the protective tube extends to the interior of the docking tube.

[0011] As a further improvement, a side of the protection tube close to the docking tube is provided with an electromagnet arranged on the output end, and the electromagnet is connected to the electrical appliance outside the docking cylinder through an elastic lead.

[0012] As a further improvement, the separation member includes a synchronization disk connected to several lower driving members, a mounting hole for making way for the main driving member is opened in the middle of the synchronization disk, and several separation frames are set on the synchronization disk at positions corresponding to the auxiliary oscillation zones.

[0013] As a further improvement, the separation frame includes a first separation plate and a second separation plate mounted on the synchronization disk, the first separation plate faces the secondary oscillation zone, and the second separation plate faces the primary oscillation zone.

[0014] The present invention also provides a method for preparing a sample for detecting pesticide residues in tea leaves, which uses the above-mentioned device for preparing a sample for detecting pesticide residues in tea leaves, and comprises the following steps: S1: Grind the tea leaves at room temperature and shake them thoroughly to form a sample. Place the sample in a polyethylene bottle and store it at -18°C until use. S2: Weigh 2 g of sample into a 50 mL sample tube, place the centrifuge tube into the sample preparation device for tea pesticide residue detection, add 8 mL of ultrapure water and vortex mix for 0.6 min, let it stand for 30 min, add 15 mL of acetonitrile and 2 glass homogenizers, vortex mix for 0.6 min, then add 6 g of anhydrous magnesium sulfate and 1.5 g of sodium acetate, shake for 1 min, and then rotate at 5000 r / min. -1 Centrifuge for 4 minutes at a frequency of S3: Take 10 mL of the supernatant of S2 and transfer it to the QuEChERS purification bag. Vortex mix for 1 minute and then spin at 5000 r / min. -1 Centrifuge for 3 min at a frequency of 100 nm and accurately transfer 5 mL of supernatant into a 10 mL test tube. S4: After the instrument stops, take the 10 mL test tube from S3 out of the sample preparation device for leaf pesticide residue detection and place it in the fully automatic parallel concentrator. After nitrogen purging until almost dry, dilute to 1 mL with a mixed aqueous solution of methanol and acetonitrile; S5: Pass 1 mL of liquid through a 0.22 μm microporous filter membrane and place it into a sample vial for testing.

[0015] As a further improvement, the QuEChERS purification package contains 600 mg anhydrous magnesium sulfate, 50 mg PSA, and 100 mg GCB.

[0016] The beneficial effects of the present invention are: It is difficult to achieve separation between various areas in small-scale equipment with the existing technology. Samples of different weights and concentrations are difficult to distinguish, which leads to easy confusion between different samples and easy diffusion of a part of the dispersed fluid. Therefore, the present invention sets a multifunctional linkage structure. First, for the experimental group with the same weight and the same buffer solution, the main oscillation zone and the auxiliary oscillation zone can be connected by a linkage part, and a plurality of samples to be tested of the same type can be formed at the same time by a single drive of the main driving part. Secondly, the main oscillation zone and the auxiliary oscillation zone can be separated, and control groups with different weights and different buffer solutions can be tested separately. Centrifugation, vortexing and other operations can be performed synchronously in the same time period to improve the overall experimental progress. The effect of a large-scale device can be achieved only in a small device.

[0017] Since the auxiliary oscillation zone has two states, the structure that drives it cannot be in a fixed state. Therefore, the present invention provides a connecting piece at the lower end of the auxiliary oscillation zone and a matching seat on the auxiliary push rod motor, so that the auxiliary push rod motor is embedded in the area covered by the auxiliary oscillation zone when it needs to cooperate with the auxiliary oscillation zone, and is disengaged when the auxiliary oscillation zone operates synchronously with the main oscillation zone, thereby achieving a dual-use effect.

[0018] In order to improve the interaction effect between the mating seat and the connecting piece and avoid the separation of the two under high-speed centrifugal conditions, the connecting piece of the present invention has an internal hexagonal structure, which can better fit with the hexagonal structure of the mating seat when mated. In order to avoid the edge becoming rounded due to long-term friction, the present invention also provides protrusions and card points on the inner and outer sides of the connecting piece and the mating seat respectively to achieve multi-point friction interference and ensure the stability of each structure under high-speed centrifugal conditions.

[0019] If the auxiliary oscillation zone needs to form a synchronization effect with the main oscillation zone, it needs to form a link with the main oscillation zone. Therefore, the outer side of the linkage part of the present invention is also provided with a plurality of docking tubes installed at the lower end of the main oscillation zone. Cooperating with the docking part on the auxiliary oscillation zone, the two can form a certain link, and then when the main oscillation zone is in motion, the auxiliary oscillation zone can be driven to link.

[0020] In order to achieve the connection and separation effect of the docking parts, the power of the docking parts of the present invention is set as a docking cylinder, which is more stable and not easy to deform compared to the push rod structure. In order to make the entire matching process more stable, the present invention also provides a protective cylinder on the output end of the docking cylinder to reduce the stress generated at the contact position, thereby enabling the upper limit of the centrifugal speed to be improved.

[0021] Whether it is the centrifugal rotation of the main oscillation zone itself or the centrifugal rotation of the auxiliary oscillation zone, both are at more than 1,000 revolutions per minute. If only the fitting effect of the connecting tube and the protective tube itself is used, it is easy to separate the auxiliary oscillation zone from the main oscillation zone. Therefore, the present invention arranges an electromagnet on the outside of the protective tube, and through strong attraction with the metal connecting tube, the entire auxiliary oscillation zone is tightly adsorbed on the main oscillation zone, and can maintain a relatively stable state even in a state of more than 1,000 revolutions per minute.

[0022] However, during the process of different groups of control experiments, different liquids need to be continuously added during the process, so the sample tube needs to be open. However, in the centrifugal state, some volatile substances may evaporate, which will affect other groups of experiments. Therefore, the present invention provides a lower separation structure based on the multi-functional linkage structure. When the main oscillation zone and the auxiliary oscillation zone perform their different functions, the separation member is pushed out by the lower driving member to achieve separation between the two areas, so that different test areas do not affect each other, thereby ensuring the accuracy of the single sample and thus ensuring the accuracy of subsequent detection.

[0023] During the separation process of the separation parts, not only a single separation segment is formed, but separation segments are formed in all areas of the secondary oscillation zone, so there is no need to judge at which processing position the control group is. Therefore, the separation frames in the separation parts of the present invention are all arranged on the synchronous disk, and the synchronous disk can be synchronously driven by the driving member so that all the separation frames are simultaneously separated between the secondary oscillation zone and the main oscillation zone, thereby completing the establishment of the separation surface.

[0024] During the separation process, not only the secondary oscillation zone may affect the main oscillation zone, but the main oscillation zone may also affect the main oscillation zone. Therefore, the two separation plates of the separation frame of the present invention are both set to an arc-shaped structure, and are both adapted to the secondary oscillation zone and the main oscillation zone, so as not to affect their rotation state, while achieving a separation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 It is a schematic diagram of the external structure of the present invention.

[0027] Figure 2 It is a schematic diagram of the internal structure of the present invention.

[0028] Figure 3 This invention Figure 2Front view of .

[0029] Figure 4 It is a structural diagram of the coordination between the oscillating platform and the multifunctional linkage structure of the present invention.

[0030] Figure 5 This invention Figure 4 Top view of .

[0031] Figure 6 This invention Figure 5 Cross-section view at AA in the middle.

[0032] Figure 7 It is a bottom view structural schematic diagram of the docking piece of the present invention.

[0033] Figure 8 It is a structural schematic diagram of the lower separation structure of the present invention.

[0034] In the picture: Machine 10, three-axis gantry moving frame 20, feeding structure 30, oscillation table 40, main oscillation zone 41, auxiliary oscillation zone 42, tube body transfer structure 50, sample transfer rack 60, multi-functional linkage structure 70, main driving part 71, auxiliary driving part 72, auxiliary push rod motor 721, matching seat 722, card point 723, connecting part 73, docking tube 741, docking part 742, docking cylinder 7421, output end 7422, protective tube 7423, electromagnet 7424, elastic lead 7425, electrical appliance 7426, protrusion 733, lower partition structure 80, separation part 81, synchronization disk 811, mounting hole 812, separation rack 813, first partition plate 8131, second partition plate 8132, lower driving part 82. DETAILED DESCRIPTION

[0035] All embodiments of the present invention are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0036] In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as referring to the purpose, technical solutions and advantages of the methods. To be clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work indicate or imply relative importance or implicitly indicate the number of indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0037] Reference Figures 1 to 8 As shown, a device for preparing test samples for detecting pesticide residues in tea leaves comprises: a machine platform 10, a three-axis gantry moving frame 20 is provided on the machine platform 10, a feeding structure 30 for adding reactants to the sample tube is provided on the three-axis gantry moving frame 20, an oscillating table 40 for placing the sample tube is provided on the upper end of the machine platform 10, a tube body transfer structure 50 is further provided on the other side of the feeding structure 30, a sample transfer rack 60 is provided on one side of the machine platform 10, the tube body transfer structure 50 transfers the mixed sample tube to the sample transfer rack 60, and further comprises: a multifunctional linkage structure 70, the oscillating table 40 comprises a main oscillation area 41 and a plurality of auxiliary oscillation areas 42 arranged on the periphery of the main oscillation area 41, the multifunctional linkage structure 70 comprises a main driving member 71 arranged below the main oscillation area 41, and an auxiliary driving member 72 is movably installed at the lower end of the auxiliary oscillation area 42, and the auxiliary driving member 72 is connected to the auxiliary oscillation area 40 through a connecting member 73. 2, the side of the secondary oscillation zone 42 close to the main oscillation zone 41 is connected to the main oscillation zone 41 through a linkage member 74. When the same sample tube is placed in the main oscillation zone 41, the linkage member 74 between the secondary oscillation zone 42 and the main oscillation zone 41 is separated, and the main driving member 71 drives the main oscillation zone 41 to rotate alone. When different sample tubes are placed in the main oscillation zone 41 and the secondary oscillation zone 42, the secondary oscillation zone 42 and the main oscillation zone 41 are linked by the linkage member 74, and the secondary driving member 72 is separated from the secondary oscillation zone 42, so that the secondary oscillation zone 42 can be driven to rotate when the main oscillation zone 41 rotates. The lower separation structure 80 includes a separation member 81 provided at the lower end of the main oscillation zone 41, and a lower driving member 82 is provided at the lower end of the separation member 81. When the main oscillation zone 41 and the secondary oscillation zone 42 are separated, the lower driving member 82 pushes the separation member 81 upward and separates it between the main oscillation zone 41 and the secondary oscillation zone 42.

[0038] During the preparation stage, the tea leaves are initially placed on the oscillating table 40, and all substances added during the preparation process are added through the feeding structure 30. After the preparation process is completed, the sample tube is transferred to the sample transfer rack 60 through the tube transfer structure 50, waiting to be taken in the next stage.

[0039] It is difficult to achieve separation between various areas in small-scale equipment with the existing technology. Samples of different weights and concentrations are difficult to distinguish, which leads to easy confusion between different samples and easy diffusion of a part of the dispersed fluid. Therefore, the present invention sets a multifunctional linkage structure 70. First, for the experimental group with the same weight and the same buffer solution, the main oscillation zone 41 and the auxiliary oscillation zone 42 can be connected by the linkage part 74, and a plurality of samples to be tested of the same type can be formed at the same time by a single drive of the main driving part 71. Secondly, the main oscillation zone 41 and the auxiliary oscillation zone 42 can be separated to experiment with control groups of different weights and different buffer solutions respectively, and centrifugation, vortexing and other operations can be performed synchronously in the same time period to improve the overall experimental progress. The effect of a large-scale device can be achieved only in a small device.

[0040] Since the auxiliary oscillation zone 42 has two states, the structure that drives it cannot be in a fixed state. Therefore, the auxiliary driving component 72 of this embodiment includes an auxiliary push rod motor 721 arranged on the machine 10, and a matching seat 722 is provided on the output end of the auxiliary push rod motor 721. The matching seat 722 is a hexagonal structure, and the matching seat 722 is fixed to the lower end of the auxiliary oscillation zone 42. A number of card points 723 are provided on the inner side of the matching seat 722. By providing a connecting member 73 at the lower end of the auxiliary oscillation zone 42 and providing a matching seat 722 on the auxiliary push rod motor 721, the auxiliary push rod motor 721 is embedded in the area covered by the auxiliary oscillation zone 42 when it needs to cooperate with the auxiliary oscillation zone 42, and is disengaged when the auxiliary oscillation zone 42 operates synchronously with the main oscillation zone 41, thereby achieving a dual-use effect.

[0041] In order to improve the interaction effect between the mating seat 722 and the connecting member 73 and avoid the separation of the two under high-speed centrifugal conditions, the inner side of the connecting member 73 of this embodiment is an inner hexagonal structure, and the mating seat 722 is pushed out by the auxiliary push rod motor 721 and cooperates with the connecting member 73. A number of protrusions 733 are provided inside the connecting member 73, and the card points 723 and the protrusions 733 are located at the same height and are staggered with each other. The connecting member 73 is an inner hexagonal structure, which can better fit with the hexagonal structure of the mating seat 722 when mated. In order to avoid the edge becoming rounded due to long-term friction, the present invention also provides protrusions 733 and card points 723 on the inner and outer sides of the connecting member 73 and the mating seat 722 respectively to achieve multi-point friction interference and ensure the stability of each structure under high-speed centrifugal conditions.

[0042] If the secondary oscillation zone 42 needs to form a synchronization effect with the main oscillation zone 41, it needs to form a link with the main oscillation zone 41. Therefore, the linkage member 74 of this embodiment includes a plurality of docking tubes 741 arranged below the main oscillation zone 41, and a docking member 742 is provided at the lower end of the secondary oscillation zone 42. When the secondary oscillation zone 42 moves synchronously with the main oscillation zone 41, the docking member 742 is pushed out and cooperates with the docking tube 741. The outer side of the linkage member 74 is also provided with a plurality of docking tubes 741 installed at the lower end of the main oscillation zone 41. When combined with the docking member 742 on the secondary oscillation zone 42, the two can form a certain link, and then when the main oscillation zone 41 moves, the secondary oscillation zone 42 can be driven to link.

[0043] In order to achieve the connection and separation effect of the docking part 742, the docking part 742 of this embodiment includes a docking cylinder 7421 arranged on the outside of the connecting part 73, and a protective cylinder 7423 is sleeved on the output end 7422 of the docking cylinder 7421. The protective cylinder 7423 extends to the interior of the docking cylinder 741. The power of the docking part 742 is set to the docking cylinder 7421, which is more stable and not easy to deform compared to the push rod structure. In order to make the entire matching process more stable, the present invention also sets a protective cylinder 7423 on the output end 7422 of the docking cylinder 7421, so as to reduce the stress generated at the contact position, thereby enabling the upper limit of the centrifugal rate to be improved.

[0044] Both the centrifugal rotation of the main oscillation zone 41 itself and the centrifugal rotation of the auxiliary oscillation zone 42 are at more than 1,000 revolutions per minute. If only the fitting effect of the docking tube 741 and the protective tube 7423 itself is used, it is easy to separate the auxiliary oscillation zone 42 from the main oscillation zone 41. Therefore, the protective tube 7423 of this embodiment is provided with a circle of electromagnets 7424 arranged on the output end 7422 on the side close to the docking tube 741. The electromagnet 7424 is connected to the electrical appliance 7426 on the outside of the docking cylinder 7421 through an elastic lead 7425. By arranging the electromagnet 7424 on the outside of the protective tube 7423 and by strongly attracting the metal docking tube 741, the entire auxiliary oscillation zone 42 is tightly adsorbed on the main oscillation zone 41, and can remain in a relatively stable state even at more than 1,000 revolutions per minute.

[0045] However, during the process of conducting different groups of control experiments, different liquids need to be continuously added during the process, so the sample tube needs to be open. However, in the centrifugal state, some volatile substances may evaporate, which will affect other groups of experiments. Therefore, the present invention provides a lower partition structure 80 based on the multi-functional linkage structure 70. When the main oscillation zone 41 and the auxiliary oscillation zone 42 perform their different functions, the separator 81 is pushed out by the lower driving member 82 to achieve separation between the two areas, so that different test areas do not affect each other, thereby ensuring the accuracy of the single sample and thus ensuring the accuracy of subsequent detection.

[0046] During the separation process of the separation member 81, it not only forms a single separation segment, but also forms separation segments in all areas of the secondary oscillation zone 42, so there is no need to judge at which processing position the control group is. Therefore, the separation member 81 of this embodiment includes a synchronization disk 811 connected to several lower driving members 82, and the middle part of the synchronization disk 811 is provided with a mounting hole 812 for making way for the main driving member 71. Several separation racks 813 are provided on the synchronization disk 811 at positions corresponding to the secondary oscillation zone 42. The separation racks 813 in the separation member 81 are all set on the synchronization disk 811, and the synchronization disk 811 can be synchronously driven by the driving member 82, so that all the separation racks 813 are simultaneously separated between the secondary oscillation zone 42 and the main oscillation zone 41, thereby completing the establishment of the separation surface.

[0047] During the separation process, not only the secondary oscillation zone 42 may affect the main oscillation zone 41, but the main oscillation zone 41 may also affect the main oscillation zone 41. Therefore, the separation frame 813 of this embodiment includes a first separation plate 8131 and a second separation plate 8132 installed on the synchronization disk 811. The first separation plate 8131 faces the secondary oscillation zone 42, and the second separation plate 8132 faces the main oscillation zone 41. The two separation plates of the separation frame 813 are both configured as arc-shaped structures and are both adapted to the secondary oscillation zone 42 and the main oscillation zone 41, so as not to affect their rotation state while achieving a separation effect.

[0048] Another embodiment of the present invention further discloses a method for preparing a sample for detecting pesticide residues in tea leaves, which uses the above-mentioned device for preparing a sample for detecting pesticide residues in tea leaves, and is characterized by comprising the following steps: S1: Grind the tea leaves at room temperature and shake them thoroughly to form a sample. Place the sample in a polyethylene bottle and store it at -18°C until use. S2: Weigh 2 g of sample into a 50 mL sample tube, place the centrifuge tube into the sample preparation device for tea pesticide residue detection, add 8 mL of ultrapure water, vortex mix for 0.6 min, let it stand for 30 min, add 15 mL of acetonitrile and 2 glass homogenizers, vortex mix for 0.6 min, then add 6 g of anhydrous magnesium sulfate and 1.5 g of sodium acetate, shake for 1 min, and then rotate at 5000 r / min. -1 Centrifuge for 4 min at a frequency of S3: Take 10 mL of the supernatant of S2 and transfer it to the QuEChERS purification pack. Vortex mix for 1 min and then spin at 5000 r / min. -1 Centrifuge for 3 min at a frequency of 100 nm and accurately transfer 5 mL of supernatant into a 10 mL test tube. S4: After the instrument stops, take out the S310 mL test tube from the sample preparation device for leaf pesticide residue detection and place it in the fully automatic parallel concentrator. After nitrogen purging until almost dry, dilute to 1 mL with a mixed aqueous solution of methanol and acetonitrile; S5: Pass 1 mL of liquid through a 0.22 μm microporous filter membrane and place it into a sample vial for testing.

[0049] Furthermore, the QuEChERS purification package contains 600 mg of anhydrous magnesium sulfate, 50 mg of PSA, and 100 mg of GCB.

[0050] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A device for preparing test samples for detecting pesticide residues in tea, characterized in that: include: A machine (10), wherein a three-axis gantry movable frame (20) is provided on the machine (10), a feeding structure (30) for adding reactants to a sample tube is provided on the three-axis gantry movable frame (20), an oscillating table (40) for placing the sample tube is provided at the upper end of the machine (10), a tube transfer structure (50) is further provided on the other side of the feeding structure (30), a sample transfer frame (60) is provided on one side of the machine (10), the tube transfer structure (50) transfers the mixed sample tube to the sample transfer frame (60), and further comprising: A multifunctional linkage structure (70), wherein the oscillation table (40) comprises a main oscillation zone (41) and a plurality of auxiliary oscillation zones (42) arranged on the periphery of the main oscillation zone (41), wherein the multifunctional linkage structure (70) comprises a main driving member (71) arranged below the main oscillation zone (41), wherein the lower end of the auxiliary oscillation zone (42) is movably mounted with an auxiliary driving member (72), wherein the auxiliary driving member (72) is connected to the auxiliary oscillation zone (42) via a connecting member (73), and the side of the auxiliary oscillation zone (42) close to the main oscillation zone (41) is connected to the main oscillation zone (41) via a linkage member (74). Then, when the same sample tube is placed in the main oscillation zone (41), the linkage member (74) between the auxiliary oscillation zone (42) and the main oscillation zone (41) is separated, and the main driving member (71) drives the main oscillation zone (41) to rotate alone; when different sample tubes are placed in the main oscillation zone (41) and the auxiliary oscillation zone (42), the auxiliary oscillation zone (42) and the main oscillation zone (41) are linked by the linkage member (74), and the auxiliary driving member (72) is separated from the auxiliary oscillation zone (42), so that the auxiliary oscillation zone (42) is driven to rotate when the main oscillation zone (41) rotates; The lower separation structure (80) comprises a separation member (81) arranged at the lower end of the main oscillation zone (41), and a lower driving member (82) is provided at the lower end of the separation member (81). When the main oscillation zone (41) is separated from the auxiliary oscillation zone (42), the lower driving member (82) pushes the separation member (81) upward and separates it between the main oscillation zone (41) and the auxiliary oscillation zone (42).

2. A device for preparing test samples for detecting pesticide residues in tea according to claim 1, characterized in that: The auxiliary driving member (72) includes an auxiliary push rod motor (721) arranged on the machine (10), and a matching seat (722) is provided on the output end of the auxiliary push rod motor (721). The matching seat (722) is a hexagonal structure. The matching seat (722) is fixed to the lower end of the auxiliary oscillation area (42), and a plurality of card points (723) are provided on the inner side of the matching seat (722).

3. A device for preparing test samples for detecting pesticide residues in tea according to claim 2, characterized in that: The inner side of the connecting member (73) is a hexagonal structure. The matching seat (722) is matched with the connecting member (73) after being pushed out by the auxiliary push rod motor (721). A plurality of protrusions (733) are provided inside the connecting member (73). The locking points (723) and the protrusions (733) are located at the same height and are staggered with each other.

4. A device for preparing test samples for detecting pesticide residues in tea according to claim 3, characterized in that: The linkage member (74) includes a plurality of docking cylinders (741) arranged below the main oscillation zone (41), and a docking member (742) is provided at the lower end of the auxiliary oscillation zone (42). When the auxiliary oscillation zone (42) moves synchronously with the main oscillation zone (41), the docking member (742) is pushed out and cooperates with the docking cylinder (741).

5. A device for preparing test samples for detecting tea pesticide residues according to claim 4, characterized in that: The docking member (742) includes a docking oil cylinder (7421) arranged outside the connecting member (73), and a protective tube (7423) is sleeved on the output end (7422) of the docking oil cylinder (7421), and the protective tube (7423) extends into the interior of the docking tube (741).

6. A device for preparing test samples for detecting pesticide residues in tea according to claim 5, characterized in that: An electromagnet (7424) is provided on one side of the protective tube (7423) close to the docking tube (741) and is sleeved on the output end (7422). The electromagnet (7424) is connected to an electrical appliance (7426) outside the docking cylinder (7421) via an elastic lead (7425).

7. A device for preparing test samples for detecting pesticide residues in tea according to claim 6, characterized in that: The separation member (81) includes a synchronization disk (811) connected to a plurality of lower driving members (82). A mounting hole (812) for making way for the main driving member (71) is provided in the middle of the synchronization disk (811). A plurality of separation racks (813) are provided on the synchronization disk (811) at positions corresponding to the auxiliary oscillation zones (42).

8. The device for preparing test samples for detecting pesticide residues in tea according to claim 7, characterized in that: The separation frame (813) includes a first partition plate (8131) and a second partition plate (8132) mounted on the synchronization disk (811), wherein the first partition plate (8131) faces the secondary oscillation zone (42), and the second partition plate (8132) faces the primary oscillation zone (41).

9. A method for preparing a sample for detecting pesticide residues in tea leaves, using the device for preparing a sample for detecting pesticide residues in tea leaves according to any one of claims 1 to 8, characterized in that: The following steps are included: S1: Grind the tea leaves at room temperature and shake them thoroughly to form a sample. Place the sample in a polyethylene bottle and store it at -18°C until use. S2: Weigh 2 g of sample into a 50 mL sample tube, place the centrifuge tube into the sample preparation device for tea pesticide residue detection, add 8 mL of ultrapure water, vortex mix for 0.6 min, let it stand for 30 min, add 15 mL of acetonitrile and 2 glass homogenizers, vortex mix for 0.6 min, then add 6 g of anhydrous magnesium sulfate and 1.5 g of sodium acetate, shake for 1 min, and then rotate at 5000 r / min. -1 Centrifuge for 4 minutes at a frequency of S3: Take 10 mL of the supernatant of S2 and transfer it to the QuEChERS purification pack. Vortex mix for 1 min and then spin at 5000 r / min. -1 Centrifuge for 3 min at a frequency of 100 nm and accurately transfer 5 mL of supernatant into a 10 mL test tube. S4: After the instrument stops, take the 10 mL test tube from S3 out of the sample preparation device for leaf pesticide residue detection and place it in the fully automatic parallel concentrator. After nitrogen purging until almost dry, dilute to 1 mL with a mixed aqueous solution of methanol and acetonitrile; S5: Pass 1 mL of liquid through a 0.22 μm microporous filter membrane and place it into a sample vial for testing.

10. The method for preparing a sample for detecting pesticide residues in tea according to claim 9, wherein: The QuEChERS purification kit contains 600 mg anhydrous magnesium sulfate, 50 mg PSA, and 100 mg GCB.

Images