Rapid detection method and device for pesticide residues in wheat by sers sensor

Abstract

The application discloses a rapid detection method and device for pesticide residues in wheat by using a SERS sensor, and relates to the technical field of pesticide residue detection; the device comprises a device bottom plate and a Raman spectrometer, a barrel is fixedly arranged on one side of the device bottom plate close to the Raman spectrometer, and a door plate is rotatably arranged on the outer wall of the barrel; the signal enhancement effect and mechanism between single noble metal nanomaterials, noble metal composite materials, noble metal / non-noble metal composite materials, non-noble metal composite materials and Raman signal molecules are studied, so that the preparation of low-cost SERS nanosubstrate materials is realized; based on the low-cost SERS nanosubstrate materials, the screening of high-specificity molecular recognition elements and the construction of new Raman probes with high sensitivity and high specificity are highlighted; based on the constructed low-cost and efficient SERS substrate and the new Raman probe, an artificial intelligence algorithm is used to establish a pesticide residue quantitative prediction model, so that accurate identification and rapid detection of pesticide residues in wheat are realized.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of pesticide residue detection, in particular to a wheat pesticide residue rapid detection method and device of a SERS sensor. BACKGROUND

[0002] Food safety is related to people's health interests, and pesticide residue detection is an important means to guarantee food quality and safety, however, the existing technology has the following problems when detecting pesticide residues in food:

[0003] 1. The high cost, complicated operation and time-consuming defects restrict the application of traditional chromatography and mass spectrometry methods in the field rapid detection of food pesticide residues. The surface enhanced Raman spectroscopy (SERS) technology has great application potential in the field of pesticide residue detection due to its high sensitivity, rapidness and simple sample processing in trace substance detection, however, SERS still faces problems such as expensive nanometer material of the substrate, weak specificity of pesticide molecule detection, lack of deep application of deep learning algorithm model, and lack of integrated portable field rapid detection equipment for food pesticide residues;

[0004] 2. When the existing technology detects pesticide residues in wheat samples, the wheat samples are not convenient to remove dust and impurities, and when the wheat samples accompanied by impurities and dust are placed in the Raman spectrometer for detection, the impurities and dust affect the accuracy of the detection value. In view of the above problems, the application provides a SERS sensor wheat pesticide residue rapid detection method and device to solve the above problems. SUMMARY

[0005] In order to solve the problems of expensive nanometer material of the substrate, weak specificity of pesticide molecule detection and lack of deep application of deep learning algorithm model of SERS, the purpose of the application is to provide a SERS sensor wheat pesticide residue rapid detection method and device.

[0006] To solve the above technical problems, the application adopts the following technical scheme: a SERS sensor wheat pesticide residue rapid detection method, comprising the following steps:

[0007] S1. Preparation of a new SERS substrate

[0008] The Raman signal enhancement effect and mechanism between noble metal (Au / Ag), non-noble metal (HgTe / graphene) and noble metal / non-noble metal composite nanometer material and organophosphorus pesticide omethoate universal structure antigen are studied, the action mechanism of the non-noble metal SERS nanometer substrate material on the enhanced Raman signal of the pesticide omethoate is clarified, and the non-noble metal nanometer substrate material with relatively high Raman signal enhancement efficiency is screened;

[0009] S2. Screening of molecular recognition elements, construction and characterization of a new Raman probe

[0010] Based on the specific binding of antigen and antibody, a high-sensitivity pesticide chlorpyrifos antibody is screened as a recognition element, and the optimal working concentration combination of pesticide chlorpyrifos structural antigen and antibody is studied; based on the high-sensitivity pesticide chlorpyrifos recognition antibody screened, an antibody-coupled non-noble metal (HgTe / graphene oxide) complex (Raman probe) is constructed; through methods such as atomic layer deposition, the deposition of the antibody-non-noble metal complex on the SERS substrate is realized, and a composite film is formed; the spectra of different concentrations of chlorpyrifos standard samples and the spectra of grain containing pesticide chlorpyrifos are collected respectively, the characteristic peak value of the Raman spectrum of pesticide chlorpyrifos is determined, and the specific binding of the molecular recognition element to pesticide chlorpyrifos is characterized by comparing the SERS peak intensity of pesticide chlorpyrifos with and without the addition of the antibody; based on the high-sensitivity and high-specificity antibody antigen recognition effect, a new type of Raman probe with high sensitivity and high specificity is constructed;

[0011] S3, establishment of a quantitative prediction model based on artificial intelligence algorithm

[0012] The pre-processing algorithm and classification algorithm of pesticide Raman signal are researched and screened, and the optimization and verification are carried out through the SERS data of pesticide chlorpyrifos; the prediction model for quantitative detection of wheat organic phosphorus pesticide chlorpyrifos residues under different artificial intelligence algorithms is constructed, the artificial intelligence algorithm is fused, and the wheat chlorpyrifos rapid detection method based on Raman spectrum is researched; the Raman spectrum information pre-processing and model construction algorithm are optimized, and the wheat chlorpyrifos residue Raman spectrum rapid detection technology is constructed;

[0013] S4, development of integrated Raman detection equipment

[0014] The hardware and software parts of the portable Raman spectrometer are designed and developed, the hardware design includes laser module, external light path module, miniature spectrometer module, control circuit module and sample chamber module, etc., and the Raman spectrometer is developed by self-assembly; the developed wheat organic phosphorus pesticide chlorpyrifos residue prediction model based on Raman spectrum is imported into the software, the running speed of the model is improved by optimizing the parameters of the model, the spectrometer, the prediction model and the software part are integrated, and a portable integrated Raman spectrometer is obtained.

[0015] Preferably, the device used in the wheat pesticide residue rapid detection method based on the SERS sensor comprises a device bottom plate and a Raman spectrometer, a barrel is fixedly arranged on one side of the device bottom plate close to the Raman spectrometer, a door plate is rotatably arranged on the outer wall of the barrel, a dismounting mechanism for dismounting the Raman spectrometer is arranged on the upper surface of the device bottom plate, a dust and impurity removing mechanism is arranged in the barrel, and a stirring mechanism is also arranged in the barrel.

[0016] Preferably, the upper surface of the device base plate is fixedly provided with a push handle, and the side of the device base plate away from the push handle is fixedly provided with uniformly distributed universal wheels.

[0017] Preferably, the dismounting mechanism comprises two L-shaped limiting plates, the inner walls of the two L-shaped limiting plates are fixedly provided with anti-skid pads, the inner walls of the two anti-skid pads are in movable contact with the outer wall of the Raman spectrometer, the upper surface of the device base plate is provided with a placing groove, the Raman spectrometer is in movable contact with the inner wall of the placing groove, the inner wall of the placing groove is provided with a sliding groove, the inner wall of the sliding groove is slidably connected with two sliding blocks, and the upper surface of one of the sliding blocks is fixedly connected with the lower surface of one of the L-shaped limiting plates.

[0018] Preferably, the side of the device base plate is rotatably provided with a double-headed screw rod, the double-headed screw rod penetrates through the sliding groove and is threadedly rotatably connected with the two sliding blocks, and one end of the double-headed screw rod is fixedly provided with a handle.

[0019] Preferably, the dust and impurity removing mechanism comprises a material disc, the lower surface of the material disc is provided with uniformly distributed through holes, the lower surface of the material disc is fixedly provided with a pushing seat, the side of the pushing seat away from the material disc is provided with an arc-shaped groove, the inner wall of the material cylinder is provided with two guide grooves, the inner walls of the two guide grooves are slidably connected with guide blocks, the opposite sides of the two guide blocks are fixedly connected with the outer wall of the material disc, the inner walls of the two guide grooves are fixedly provided with telescopic rods, the piston end of each telescopic rod is fixedly connected with the lower surface of the guide block, the outer walls of the two telescopic rods are movably sleeved with telescopic springs, one end of each telescopic spring is fixedly connected with the inner wall of the guide groove, and the other end of each telescopic spring is fixedly connected with the lower surface of the guide block.

[0020] Preferably, the outer wall of the material cylinder is fixedly provided with a servo motor, the driving output end of the servo motor is fixedly provided with a rotating rod, the rotating rod penetrates through the material cylinder and is rotatably connected with the material cylinder, the outer wall of the rotating rod is fixedly provided with a cam, and the cam is vertically corresponding to the arc-shaped groove.

[0021] Preferably, the outer wall of the servo motor is fixedly provided with a fixed block, and one side of the fixed block is fixedly connected with one side of the material cylinder.

[0022] Preferably, the stirring mechanism comprises a stirring rod, one end of the stirring rod is rotatably connected to the inner wall of the tray, a fixing sleeve is fixedly installed on the outer wall of the stirring rod, a plurality of rotating plates are fixedly installed on the outer wall of the fixing sleeve, a plurality of stirring blades are fixedly installed on the outer wall of the rotating plates, a transmission rod is arranged on the upper surface of the tray, a bevel gear is fixedly installed on one end of the transmission rod and one end of the stirring rod, the two bevel gears are meshed with each other, a drive gear is fixedly installed on the end of the transmission rod away from the bevel gear, and a notch is formed in the inner wall of the barrel, a toothed plate is fixedly installed on the inner wall of the notch, and the toothed plate is meshed with the drive gear.

[0023] Preferably, a fixed rod is fixedly installed on the upper surface of the tray, and a rotating sleeve is fixedly installed on the end of the fixed rod away from the tray.

[0024] Compared with the prior art, the present application has the following advantages:

[0025] 1. By studying the signal enhancement effect and mechanism between single noble metal nanomaterials, noble metal composites, noble metal / non-noble metal composites, non-noble metal composites and Raman signal molecules, the preparation of low-cost SERS nanosubstrate materials is realized; based on the low-cost SERS nanosubstrate materials, the screening of high-specificity molecular recognition elements and the construction of new Raman probes with high sensitivity and high specificity are focused on; based on the constructed low-cost and efficient SERS substrate and new Raman probe, an artificial intelligence algorithm is used to establish a pesticide residue quantitative prediction model, and the accurate identification and rapid detection of pesticide residues in wheat are realized;

[0026] 2. The Raman spectrometer is placed on the inner wall of the placing groove, and the two L-shaped limit plates are driven to move towards each other, the lower end of the Raman spectrometer is limited by the two anti-skid pads, so that the installation of the Raman spectrometer is facilitated, and the convenience of installing the Raman spectrometer is effectively improved, and the Raman spectrometer is convenient for the staff to move;

[0027] 3. The wheat seeds to be detected are placed in the tray, and the cam is driven to rotate, and the action force of the telescopic rod and the telescopic spring makes the tray reciprocatingly move up and down, and the dust and impurities in the wheat seeds are discharged through the plurality of through holes when the tray reciprocatingly moves up and down, so that the dust removal and impurity removal of the wheat seeds to be detected are facilitated, and the accuracy of the subsequent pesticide residue detection result is effectively improved;

[0028] 4, by the rotation of the stirring rod, the stirring rod through the fixed sleeve makes the rotating plate and the stirring blade reciprocating rotation, the stirring blade reciprocating rotation at the same time to the wheat sample in the tray is stirred, thereby conveniently realize the stirring of the wheat sample in the process of dust removal and impurity removal, further effectively improve the effect of dust removal and impurity removal of the wheat sample. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating labor.

[0030] Figure 1 The connection diagram of the Raman spectrometer, the barrel and the device base plate of the present application.

[0031] Figure 2 The separation diagram of the Raman spectrometer and the device base plate of the present application.

[0032] Figure 3 The cross-sectional structure diagram of the device base plate and the barrel of the present application.

[0033] Figure 4 The connection diagram of the dismounting mechanism of the present application.

[0034] Figure 5 The connection diagram of the dust removal and impurity removal mechanism and the stirring mechanism of the present application.

[0035] Figure 6 The cross-sectional structure diagram of the tray and the pushing seat of the present application.

[0036] In the figure: 1, device base plate; 11, push handle; 12, universal wheel; 13, Raman spectrometer; 14, barrel; 141, chip removal hole; 15, fixed seat; 16, door plate; 17, handle; 2, dismounting mechanism; 21, L-shaped limiting plate; 22, non-slip pad; 23, placing groove; 24, sliding groove; 25, sliding block; 26, double-head screw rod; 27, handle; 3, dust removal and impurity removal mechanism; 31, tray; 32, through hole; 33, pushing seat; 34, arc groove; 35, guide groove; 36, guide block; 37, telescopic rod; 38, telescopic spring; 39, servo motor; 4, fixed block; 41, rotating rod; 42, cam; 5, stirring mechanism; 51, stirring rod; 52, fixed sleeve; 53, rotating plate; 54, stirring blade; 55, transmission rod; 56, fixed rod; 57, rotating sleeve; 58, bevel gear; 59, driving gear; 6, notch; 61, toothed plate. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0038] Embodiment: As shown in the present application, a rapid detection method for pesticide residues in wheat based on a SERS sensor is provided, comprising the following steps: Figures 1-6

[0039] S1, preparation of a novel SERS substrate

[0040] The Raman signal enhancement effect and mechanism between noble metals (Au / Ag), non-noble metals (HgTe / graphene), and noble metal / non-noble metal composite nanomaterials and the universal structure antigen of organophosphorus pesticide chlorpyrifos are studied, the mechanism of the non-noble metal SERS nanosubstrate material on the enhancement of the Raman signal of the pesticide chlorpyrifos is clarified, and the non-noble metal nanosubstrate material with relatively high Raman signal enhancement efficiency is screened;

[0041] S2, screening of a molecular recognition element, and construction and characterization of a novel Raman probe

[0042] Based on the specific binding of antigens and antibodies, a pesticide chlorpyrifos antibody with high sensitivity is screened as a recognition element, and the optimal working concentration combination of the pesticide chlorpyrifos structure antigen and the antibody is studied; based on the screened high-sensitivity pesticide chlorpyrifos recognition antibody, an antibody-coupled non-noble metal (HgTe / oxidized graphene) composite (Raman probe) is constructed; through methods such as atomic layer deposition, the antibody-non-noble metal composite is deposited on the SERS substrate to form a composite film; the spectra of chlorpyrifos standard samples with different concentrations and the spectra of grain containing pesticide chlorpyrifos are collected, respectively, to determine the characteristic peak value of the Raman spectrum of pesticide chlorpyrifos, and the specific binding of the molecular recognition element to pesticide chlorpyrifos is characterized by comparing the SERS peak intensity of pesticide chlorpyrifos with and without the addition of the antibody; based on the high-sensitivity and high-specificity antibody antigen recognition effect, a novel Raman probe with high sensitivity and high specificity is constructed;

[0043] S3, establishment of a quantitative prediction model based on an artificial intelligence algorithm

[0044] The preprocessing algorithm and the classification algorithm of the pesticide Raman signal are studied and screened, and the optimization and verification are performed through the pesticide chlorpyrifos SERS data; the prediction model for the quantitative detection of wheat organophosphorus pesticide chlorpyrifos residues under different artificial intelligence algorithms is constructed, the artificial intelligence algorithm is fused, and the rapid detection method for wheat chlorpyrifos based on Raman spectrum is studied; the Raman spectrum information preprocessing and model construction algorithm are optimized, and the rapid detection technology for wheat chlorpyrifos residue Raman spectrum is constructed;​

[0045] S4, development of integrated Raman detection equipment

[0046] The hardware part of the portable Raman spectrometer 13 is designed and developed, including a laser module, an external light path module, a miniature spectrometer module, a control circuit module, a sample chamber module, etc. The Raman spectrometer 13 is developed by self-assembly. The developed wheat organophosphorus pesticide chlorpyrifos residue prediction model based on Raman spectrum is introduced into the software. The operation speed of the model is improved by optimizing the parameters of the model. The spectrometer, the prediction model and the software part are integrated to obtain the portable integrated Raman spectrometer 13.

[0047] By adopting the above technical scheme, the signal enhancement effect and mechanism between single noble metal nanomaterial, noble metal composite material, noble metal / non-noble metal composite material, non-noble metal composite material and Raman signal molecules are studied to realize the preparation of low-cost SERS nanosubstrate material; based on the low-cost SERS nanosubstrate material, the screening of high-specificity molecular recognition elements and the construction of new Raman probes with high sensitivity and high specificity are focused on; based on the constructed low-cost and efficient SERS substrate and new Raman probe, an artificial intelligence algorithm is used to establish a pesticide residue quantitative prediction model to realize accurate identification and rapid detection of pesticide residues in wheat.

[0048] The device used in the method for rapidly detecting pesticide residues in wheat based on a SERS sensor includes a device base plate 1 and a Raman spectrometer 13. A barrel 14 is fixedly arranged on one side of the device base plate 1 close to the Raman spectrometer 13. A door plate 16 is rotatably arranged on the outer wall of the barrel 14. A dismounting mechanism 2 for dismounting the Raman spectrometer 13 is arranged on the upper surface of the device base plate 1. A dust and impurity removing mechanism 3 is arranged in the barrel 14. A stirring mechanism 5 is also arranged in the barrel 14.

[0049] By adopting the above technical scheme, the dismounting mechanism 2 is arranged to facilitate the installation and dismounting of the Raman spectrometer 13. The dust and impurity removing mechanism 3 is arranged to facilitate the dust and impurity removal of the wheat sample. The stirring mechanism 5 is arranged to facilitate the stirring of the wheat sample, thereby improving the dust and impurity removal effect of the wheat sample.

[0050] A handle 11 is fixedly arranged on the upper surface of the device base plate 1. Universal wheels 12 are fixedly arranged on the side of the device base plate 1 away from the handle 11. Chip removal holes 141 are arranged at the bottom end of the barrel 14. Fixed seats 15 are fixedly arranged on one end of the barrel 14 close to the chip removal holes 141. The other end of the fixed seats 15 is fixedly connected with the upper surface of the device base plate 1. A handle 17 is fixedly arranged on one side of the door plate 16.

[0051] By adopting the above technical solution, by setting the push handle 11 and the universal wheel 12, the push handle 11 and the universal wheel 12 make it easy for the staff to move the Raman spectrometer 13, by setting the fixed seat 15, the fixed seat 15 supports and fixes the barrel 14, thereby improving the stability of the barrel 14, and by pulling the handle 17 to open the door panel 16, it is convenient for the staff to add wheat samples into the barrel 14.

[0052] The disassembly and assembly mechanism 2 includes two L-shaped limit plates 21, and the inner walls of the two L-shaped limit plates 21 are fixedly installed with anti-slip pads 22. The inner walls of the two anti-slip pads 22 are in movable contact with the outer wall of the Raman spectrometer 13. A placement groove 23 is provided on the upper surface of the device base plate 1, and the Raman spectrometer 13 is in movable contact with the inner wall of the placement groove 23. A slide groove 24 is provided on the inner wall of the placement groove 23. Two sliders 25 are slidably connected to the inner wall of the slide groove 24. The upper surface of one slider 25 is fixedly connected to the lower surface of an L-shaped limit plate 21.

[0053] By adopting the above technical solution, when the Raman spectrometer 13 is placed inside the placement groove 23, the two sliders 25 slide toward each other along the inner wall of the slide groove 24. The two sliders 25 cause the two L-shaped limiting plates 21 and the two anti-slip pads 22 to move toward each other. The two L-shaped limiting plates 21 limit the Raman spectrometer 13 in the placement groove 23 through the two anti-slip pads 22, thereby achieving fixed installation of the Raman spectrometer 13.

[0054] A double-headed screw 26 is rotatably mounted on one side of the device base plate 1 . The double-headed screw 26 passes through the slide groove 24 and is threadedly rotatably connected to the two sliders 25 . A handle 27 is fixedly mounted on one end of the double-headed screw 26 .

[0055] By adopting the above technical solution, the knob handle 27 is turned to rotate the double-headed screw 26 , and the double-headed screw 26 causes the two sliders 25 to slide toward each other or away from each other along the inner wall of the slide groove 24 .

[0056] The dust and impurity removal mechanism 3 includes a material tray 31, the lower surface of the material tray 31 is provided with evenly distributed through holes 32, the lower surface of the material tray 31 is fixedly installed with a pushing seat 33, and the side of the pushing seat 33 away from the material tray 31 is provided with an arc groove 34, the inner wall of the barrel 14 is provided with two guide grooves 35, the inner walls of the two guide grooves 35 are slidably connected with guide blocks 36, the opposite sides of the two guide blocks 36 are fixedly connected to the outer wall of the material tray 31, the inner walls of the two guide grooves 35 are fixedly installed with telescopic rods 37, the piston end of the telescopic rod 37 is fixedly connected to the lower surface of the guide block 36, and the outer walls of the two telescopic rods 37 are movably sleeved with telescopic springs 38, one end of the telescopic spring 38 is fixedly connected to the inner wall of the guide groove 35, and the other end of the telescopic spring 38 is fixedly connected to the lower surface of the guide block 36.

[0057] By adopting the above technical scheme, the wheat sample to be detected is placed in the tray 31 by opening the door plate 16, the pushing seat 33 moves upward, the pushing seat 33 moves the tray 31 upward, and meanwhile, the tray 31 makes the two telescopic rods 37 and the two telescopic springs 38 expand through the two guide blocks 36, when the telescopic rods 37 and the telescopic springs 38 reset, the telescopic rods 37 and the telescopic springs 38 make the tray 31 vertically move downward through the guide blocks 36, and the reciprocating up-and-down movement of the tray 31 makes the dust and impurities in the wheat seeds discharge through the through holes 32.

[0058] The outer wall of the barrel 14 is fixedly provided with a servo motor 39, the driving output end of the servo motor 39 is fixedly installed with a rotating rod 41, the rotating rod 41 penetrates through the barrel 14 and is rotationally connected with the barrel 14, the outer wall of the rotating rod 41 is fixedly installed with a cam 42, and the cam 42 vertically corresponds to the arc-shaped groove 34.

[0059] By adopting the above technical scheme, the servo motor 39 is opened, the driving shaft of the servo motor 39 rotates the rotating rod 41, the rotating rod 41 rotates the cam 42, and when the protruding part of the cam 42 contacts the inner wall of the arc-shaped groove 34, the protruding part of the cam 42 moves the pushing seat 33 upward.

[0060] The outer wall of the servo motor 39 is fixedly installed with a fixed block 4, and one side of the fixed block 4 is fixedly connected with one side of the barrel 14.

[0061] By adopting the above technical scheme, the fixed block 4 is arranged to support and fix the servo motor 39, thereby improving the stability of the servo motor 39.

[0062] The stirring mechanism 5 comprises a stirring rod 51, one end of the stirring rod 51 is rotationally connected with the inner wall of the tray 31, the outer wall of the stirring rod 51 is fixedly installed with a fixed sleeve 52, the outer wall of the fixed sleeve 52 is fixedly installed with uniformly distributed rotating plates 53, the outer wall of the rotating plates 53 is fixedly installed with uniformly distributed stirring blades 54, the upper surface of the tray 31 is provided with a transmission rod 55, one end of the transmission rod 55 and one end of the stirring rod 51 are fixedly installed with bevel gears 58, the two bevel gears 58 are meshed with each other, the end of the transmission rod 55 away from the bevel gears 58 is fixedly installed with a driving gear 59, the inner wall of the barrel 14 is provided with a slot 6, the inner wall of the slot 6 is fixedly installed with a toothed plate 61, and the toothed plate 61 is meshedly connected with the driving gear 59.

[0063] When the material tray 31 reciprocatingly moves up and down, the material tray 31 synchronously moves up and down the transmission rod 55 and the driving gear 59, the toothed plate 61 reciprocatingly rotates the driving gear 59, the driving gear 59 reciprocatingly rotates the transmission rod 55, the transmission rod 55 reciprocatingly rotates the stirring rod 51 through the two intermeshing bevel gears 58, the stirring rod 51 reciprocatingly rotates the rotating plate 53 and the stirring blade 54 through the fixing sleeve 52, and the stirring blade 54 reciprocatingly rotates and stirs the wheat sample in the material tray 31.

[0064] The upper surface of the material tray 31 is fixedly installed with the fixed rod 56, and the end, away from the material tray 31, of the fixed rod 56 is fixedly installed with the rotating sleeve 57, and the transmission rod 55 penetrates through the rotating sleeve 57 and is rotationally connected with the inner wall of the rotating sleeve 57.

[0065] Through the above technical scheme, the fixed rod 56 and the rotating sleeve 57 support the transmission rod 55, and the material tray 31 synchronously moves up and down the transmission rod 55 through the fixed rod 56 and the rotating sleeve 57.

[0066] Working principle: through the study of the signal enhancement effect and mechanism between single noble metal nanomaterial, noble metal composite material, noble metal / non-noble metal composite material, non-noble metal composite material and Raman signal molecules, the preparation of low-cost SERS nanosubstrate material is realized; based on the low-cost SERS nanosubstrate material, the screening of high-specificity molecular recognition elements and the construction of new Raman probes with high sensitivity and high specificity are focused on; based on the constructed low-cost and efficient SERS substrate and new Raman probe, an artificial intelligence algorithm is used to establish a pesticide residue quantitative prediction model, realizing accurate identification and rapid detection of pesticide residues in wheat;

[0067] By placing the Raman spectrometer 13 on the inner wall of the placing groove 23 and rotating the handle 27, the handle 27 rotates the double-head screw rod 26, the double-head screw rod 26 rotates the two sliders 25 along the inner wall of the sliding groove 24, the two sliders 25 move the two L-shaped limiting plates 21 and the two anti-skid pads 22 towards each other, and after the inner walls of the two anti-skid pads 22 and the outer wall of the Raman spectrometer 13 are in close contact, the handle 27 is stopped, at this time, the two L-shaped limiting plates 21 limit the lower end of the Raman spectrometer 13 through the two anti-skid pads 22, thereby conveniently installing the Raman spectrometer 13, and effectively improving the convenience of installing the Raman spectrometer 13, and facilitating the movement of the Raman spectrometer 13 by the staff.

[0068] By opening the door plate 16, the wheat seeds to be detected are placed in the tray 31, and then the servo motor 39 is started, the driving shaft of the servo motor 39 drives the rotating rod 41 to rotate, the rotating rod 41 drives the cam 42 to rotate, when the protruding part of the cam 42 contacts with the inner wall of the arc groove 34, the protruding part of the cam 42 drives the push base 33 to move upwards, the push base 33 drives the tray 31 to move upwards, at the same time, the tray 31 drives the two guide blocks 36 to slide vertically upwards along the inner wall of the two guide grooves 35, the two guide blocks 36 drive the two telescopic rods 37 and the two telescopic springs 38 to stretch, when the protruding part of the cam 42 is separated from the inner wall of the arc groove 34, the two telescopic rods 37 and the two telescopic springs 38 reset, the reset of the two telescopic rods 37 and the two telescopic springs 38 drives the two guide blocks 36 to slide downwards, the two guide blocks 36 drive the tray 31 to move downwards, with the reciprocating rotation of the cam 42, the tray 31 reciprocatingly moves up and down, at the same time, the tray 31 reciprocatingly moves up and down drives the dust and impurities in the wheat seeds to be detected to be discharged through the plurality of through holes 32, so that the dust removal and impurity removal of the wheat seeds to be detected are conveniently realized, and the accuracy of the subsequent pesticide residue detection result is effectively improved.

[0069] At the same time, the tray 31 drives the transmission rod 55 and the driving gear 59 to move up and down synchronously, the tooth plate 61 drives the driving gear 59 to rotate reciprocatingly, the driving gear 59 drives the transmission rod 55 to rotate reciprocatingly, the transmission rod 55 drives the stirring rod 51 to rotate reciprocatingly through the two intermeshing bevel gears 58, the stirring rod 51 drives the plurality of rotating plates 53 and the plurality of stirring blades 54 to rotate reciprocatingly through the fixed sleeve 52, at the same time, the plurality of stirring blades 54 reciprocatingly rotate to stir the wheat sample in the tray 31, so that the stirring of the wheat sample in the dust removal and impurity removal process is conveniently realized, and the effect of the dust removal and impurity removal of the wheat sample is effectively improved.

[0070] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application belong to the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A rapid detection method of pesticide residues in wheat by SERS sensor, characterized in that, It comprises the following steps: S1, preparation of SERS substrate The Raman signal enhancement effect and mechanism between noble metal Au / Ag, non-noble metal HgTe / graphene and noble metal / non-noble metal composite nanomaterials and organophosphorus pesticide general structure antigen of chlorpyrifos are studied, the action mechanism of non-noble metal SERS nanosubstrate material on the Raman signal enhancement of pesticide chlorpyrifos is clarified, and the non-noble metal nanosubstrate material with relatively high Raman signal enhancement efficiency is screened; S2, screening of molecular recognition element, construction and characterization of Raman probe Based on the specific binding of antigen and antibody, a high-sensitivity pesticide chlorpyrifos antibody is screened as a recognition element, and the optimal working concentration combination of pesticide chlorpyrifos structure antigen and antibody is studied; based on the screened high-sensitivity pesticide chlorpyrifos recognition antibody, an antibody-coupled non-noble metal HgTe / graphene composite Raman probe is constructed; through the atomic layer deposition method, the deposition of antibody-non-noble metal composite on the SERS substrate is realized, and a composite film is formed; the spectra of different concentrations of chlorpyrifos standard samples and the spectra of food containing pesticide chlorpyrifos are collected respectively, the characteristic peak value of the Raman spectrum of pesticide chlorpyrifos is determined, and the specific binding of the molecular recognition element to the pesticide chlorpyrifos is characterized by comparing the SERS peak intensity of the pesticide chlorpyrifos with and without the addition of the antibody; based on the high-sensitivity and high-specificity antibody antigen recognition effect, a high-sensitivity and high-specificity Raman probe is constructed; S3, establishment of quantitative prediction model based on artificial intelligence algorithm The pre-processing algorithm and classification algorithm of pesticide Raman signal are studied and screened, and the pre-processing algorithm and classification algorithm of pesticide Raman signal are optimized and verified through the SERS data of pesticide chlorpyrifos; the prediction model for quantitative detection of wheat organophosphorus pesticide chlorpyrifos residues under different artificial intelligence algorithms is constructed, the artificial intelligence algorithm is fused, and the wheat chlorpyrifos rapid detection method based on Raman spectrum is studied; the Raman spectrum information pre-processing and model construction algorithm constructs the wheat chlorpyrifos residue Raman spectrum rapid detection technology; S4, development of integrated Raman detection equipment The hardware design includes laser module, external light path module, miniature spectrometer module, control circuit module and sample chamber module, and the Raman spectrometer (13) is developed by self-assembly; the developed wheat organophosphorus pesticide chlorpyrifos residue prediction model based on Raman spectrum is imported into the software, the running speed of the model is improved by optimizing the parameters of the model, the spectrometer, the prediction model and the software part are integrated, and the portable integrated Raman spectrometer (13) is obtained.

2. The device used for rapid detection of pesticide residues in wheat by SERS sensor according to claim 1, comprising a device base plate (1) and a Raman spectrometer (13), characterized in that, The device bottom plate (1) is fixed with a barrel (14) on one side close to the Raman spectrometer (13), a door plate (16) is rotatably installed on the outer wall of the barrel (14), a dismounting mechanism (2) for dismounting the Raman spectrometer (13) is arranged on the upper surface of the device bottom plate (1), a dust and impurity removing mechanism (3) is arranged in the barrel (14), and a stirring mechanism (5) is further arranged in the barrel (14). The dust and impurity removing mechanism (3) comprises a material tray (31), the lower surface of the material tray (31) is provided with uniformly distributed through holes (32), the lower surface of the material tray (31) is fixedly installed with a pushing seat (33), one side of the pushing seat (33) away from the material tray (31) is provided with an arc groove (34), the inner wall of the material cylinder (14) is provided with two guide grooves (35), the inner walls of the two guide grooves (35) are both slidably connected with guide blocks (36), the opposite sides of the two guide blocks (36) and the outer wall of the material tray (31) are fixedly connected, the inner walls of the two guide grooves (35) are both fixedly installed with telescopic rods (37), the piston end of the telescopic rod (37) and the lower surface of the guide block (36) are fixedly connected, the outer walls of the two telescopic rods (37) are both movably sleeved with telescopic springs (38), one end of the telescopic spring (38) and the inner wall of the guide groove (35) are fixedly connected, the other end of the telescopic spring (38) and the lower surface of the guide block (36) are fixedly connected.

3. The apparatus for use in the method for rapid detection of pesticide residues in wheat using SERS sensor according to claim 2, wherein, The upper surface of the device bottom plate (1) is fixedly installed with a push handle (11), one side of the device bottom plate (1) away from the push handle (11) is fixedly installed with uniformly distributed universal wheels (12), the bottom end of the material cylinder (14) is provided with uniformly distributed chip removal holes (141), one end of the material cylinder (14) close to the chip removal holes (141) is fixedly installed with uniformly distributed fixing seats (15), one end of the fixing seat (15) away from the material cylinder (14) and the upper surface of the device bottom plate (1) are fixedly connected, one side of the door plate (16) is fixedly installed with a handle (17).

4. The device for use in the method for rapid detection of pesticide residues in wheat using SERS sensor according to claim 2, characterized in that, The dismounting mechanism (2) comprises two L-shaped limiting plates (21), the inner walls of the two L-shaped limiting plates (21) are both fixedly installed with anti-skid pads (22), the inner walls of the two anti-skid pads (22) and the outer wall of the Raman spectrometer (13) movably contact, the upper surface of the device bottom plate (1) is provided with a placing groove (23), the Raman spectrometer (13) and the inner wall of the placing groove (23) movably contact, the inner wall of the placing groove (23) is provided with a sliding groove (24), the inner wall of the sliding groove (24) is slidably connected with two sliding blocks (25), the upper surface of one of the sliding blocks (25) and the lower surface of one of the L-shaped limiting plates (21) are fixedly connected.

5. The apparatus for use in the method for rapid detection of pesticide residues in wheat using SERS sensor according to claim 4, wherein, One side of the device bottom plate (1) is rotatably installed with a double-head screw rod (26), the double-head screw rod (26) penetrates through the sliding groove (24) and is threadedly rotatably connected with the two sliding blocks (25), one end of the double-head screw rod (26) is fixedly installed with a handle (27).

6. The device for use in the method for rapid detection of pesticide residues in wheat using SERS sensor according to claim 2, characterized in that, The outer wall of the material cylinder (14) is fixedly provided with a servo motor (39), the driving output end of the servo motor (39) is fixedly installed with a rotating rod (41), the rotating rod (41) penetrates through the material cylinder (14) and is rotatably connected with the material cylinder (14), the outer wall of the rotating rod (41) is fixedly installed with a cam (42), the cam (42) and the arc groove (34) vertically correspond.

7. The apparatus for use in the method of rapid detection of pesticide residues in wheat using SERS sensor according to claim 6, wherein, The outer wall of the servo motor (39) is fixedly installed with a fixed block (4), one side of the fixed block (4) is fixedly connected with one side of the barrel (14).

8. The device for use in the method for rapid detection of pesticide residues in wheat according to claim 2, wherein, The stirring mechanism (5) comprises a stirring rod (51), one end of the stirring rod (51) is rotatably connected with the inner wall of the material disc (31), the outer wall of the stirring rod (51) is fixedly installed with a fixed sleeve (52), the outer wall of the fixed sleeve (52) is fixedly installed with uniformly distributed rotating plates (53), the outer wall of the rotating plate (53) is fixedly installed with uniformly distributed stirring blades (54), the upper surface of the material disc (31) is provided with a transmission rod (55), one end of the transmission rod (55) and one end of the stirring rod (51) are fixedly installed with bevel gears (58), the two bevel gears (58) are meshed with each other, the end of the transmission rod (55) away from the bevel gear (58) is fixedly installed with a driving gear (59), the inner wall of the barrel (14) is provided with a notch (6), the inner wall of the notch (6) is fixedly installed with a toothed plate (61), the toothed plate (61) is meshedly connected with the driving gear (59).

9. The apparatus for use in the method of rapid detection of pesticide residues in wheat using SERS sensor according to claim 8, characterized in that, The upper surface of the material disc (31) is fixedly installed with a fixed rod (56), the end of the fixed rod (56) away from the material disc (31) is fixedly installed with a rotating sleeve (57), the transmission rod (55) penetrates through the rotating sleeve (57) and is rotatably connected with the inner wall of the rotating sleeve (57).

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