An intelligent detection method for pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor

Abstract

The present invention belongs to the technical field of food safety detection, and specifically relates to an intelligent detection method for water-ground glutinous rice flour pollutants based on AuNTs@PDMS flexible SERS sensors. A flexible transparent PDMS film was prepared by spin coating, and coupled with AuNTs nanomaterials through interface deposition, surface modification, nanoimprinting and other technologies to prepare a high-performance flexible SERS sensor, which was applied to the rapid detection of pollutants in water-ground glutinous rice flour. The AuNTs used in the present invention are regular triangles, which have a wider local surface plasmon resonance band. The unique optical and plasma properties give them excellent SERS sensing performance and a more significant enhancement effect. The sensor prepared based on the AuNTs has good flexibility and optical transparency, can fully contact irregular surfaces, and is conducive to the in-situ detection of target analytes. In addition, the AuNTs are inexpensive, easy to make, and can be stored for a long time, with broad application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of food safety detection, and in particular relates to an intelligent detection method for pollutants in water-ground glutinous rice flour based on an AuNTs@PDMS flexible SERS sensor. Background Art

[0002] Water-milled glutinous rice flour is rich in nutrients. In addition to essential energy sources such as carbohydrates, protein, and fat, it also contains a variety of vitamins and minerals. In recent years, food poisoning incidents caused by contaminants have become common, negatively impacting consumer health. Therefore, the detection and prevention of contaminants in water-milled glutinous rice flour has become a powerful tool for protecting consumer health.

[0003] Common contaminants in water-milled glutinous rice flour include mycotoxins, heavy metals, pesticide residues, and antibiotics, which pose a significant health hazard and occur frequently. Countries worldwide have established regulations regarding contaminant residues in water-milled glutinous rice flour. In response, national standards (GB 5009.22-2016) have emerged for isotope dilution liquid chromatography-tandem mass spectrometry, high-performance liquid chromatography-pre- and post-column derivatization, enzyme-linked immunosorbent assay (ELISA), and thin-layer chromatography (TLC) to meet the demand for accurate detection. These chromatographic and immunological techniques have the following drawbacks: 1) the instrumentation is expensive, resulting in high testing costs and requiring specialized personnel; 2) detection performance is easily affected by the sample matrix and processing methods; and 3) testing must be performed in a laboratory, placing high demands on the testing environment. Furthermore, water-milled glutinous rice flour requires stringent environmental conditions. If testing cannot be completed quickly and released for sale, it can easily become contaminated with mycotoxins, pesticide residues, antibiotics, and other contaminants during processing and storage. Consequently, high demands are placed on on-site testing methods and efficiency. Therefore, a more rapid, simple, safe, and accurate method for detecting contaminants in water-milled glutinous rice flour is needed. Summary of the Invention

[0004] In order to solve the problems existing in the above-mentioned prior art, the present invention provides an intelligent detection method for pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor. An AuNTs@SERS substrate with unique optical and plasma properties is synthesized and coupled with a PDMS film to successfully prepare a high-performance flexible SERS sensor, which can realize rapid on-site detection of pollutants in water-ground glutinous rice flour.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides an intelligent detection method for pollutants in water-ground glutinous rice flour based on an AuNTs@PDMS flexible SERS sensor, comprising the following steps:

[0007] Step 1: Preparation of gold nanotriangles (AuNTs): First, cetyltrimethylammonium chloride (CTAC)-coated gold seeds are prepared. The resulting seeds are then added to the final growth solution. Finally, after a purification step, gold nanotriangles (AuNTs) are obtained.

[0008] (1) Preparation of gold seed solution: First, a tetrachloroauric acid (HAuCl4) solution is added to a cetyltrimethylammonium chloride (CTAC) solution, and then a sodium borohydride (NaBH4) solution is added under stirring. The resulting mixed solution is stored at room temperature for a period of time to obtain a gold seed solution;

[0009] (2) Preparation of growth solution:

[0010] (a) CTAC solution was added to ultrapure water, followed by HAuCl4 solution and NaI solution, and the mixture was mixed thoroughly. The resulting solution was designated as growth solution 1.

[0011] (b) HAuCl4 solution was added to CTAC solution, and then NaI solution was added and mixed evenly. The resulting solution was recorded as growth solution 2;

[0012] (c) diluting the gold seed solution prepared in step (1) by 8-12 times with CTAC solution to obtain a dilution solution; then, adding ascorbic acid solution to growth solution 1 and growth solution 2, respectively, and stirring until the solution is completely transparent to obtain mixed solution 1 and mixed solution 2; adding the dilution solution to mixed solution 1, and the solution obtained after stirring is recorded as mixed solution 3; then mixing mixed solution 3 with mixed solution 2, and the obtained solution is stored at room temperature for a period of time to obtain a crude AuNTs solution;

[0013] (3) AuNTs purification: CTAC solution was added to the crude AuNTs solution and purified at room temperature to obtain a gold nanotriangle (AuNTs) solution.

[0014] Step 2: Curing of the polymethoxysilane (PDMS) flexible film: polydimethylsiloxane and a curing agent are mixed and stirred evenly to obtain a mixture; the mixture is then poured into a mold for curing and drying to obtain a cured pure PDMS film;

[0015] Step 3: Carboxyl modification of the PDMS flexible film: The pure PDMS film prepared in step 2 is immersed in a polyacrylic acid (PAA) solution. After soaking and incubation, the pure PDMS film is taken out and washed with ultrapure water. After washing, it is dried with nitrogen to obtain a carboxyl functionalized PDMS film.

[0016] Step 4: AuNTs@PDMS flexible SERS sensor coupling (preparation of AuNTs@PDMS SERS flexible sensor using interfacial self-assembly method);

[0017] First, the gold nanotriangle (AuNTs) solution obtained in step 1 is concentrated by 1-10 times to obtain a concentrated AuNTs solution. Then, the carboxyl-functionalized PDMS film prepared in step 3 is immersed in the concentrated AuNTs solution for incubation. After incubation, the film is washed with ultrapure water and dried with nitrogen to obtain an AuNTs@PDMS film.

[0018] Step 5: Construction of AuNTs@PDMS flexible SERS sensing system:

[0019] Prepare pollutant standard solutions of different concentrations, then immerse the AuNTs@PDMS film prepared in step 4 into the pollutant standard solutions of different concentrations and incubate them at a certain temperature. After incubation, take out the AuNTs@PDMS film and collect 200-2000 cm -1 The SERS spectra within the range are plotted, and the pollutant concentration-related standard curve is drawn according to the SERS intensity signal characteristic values ​​corresponding to the pollutant standard solutions with different concentrations;

[0020] Step 6: Detection of pollutants in water-ground glutinous rice flour: Take water-ground glutinous rice flour, add deionized water, stir evenly and centrifuge, take the supernatant to obtain the sample solution; then immerse the AuNTs@PDMS film prepared in step 4 in the sample solution and incubate it under certain temperature conditions. After incubation, take out the AuNTs@PDMS film and collect 200-2000cm -1 The SERS spectrum within the range was obtained to obtain the SERS intensity signal characteristic value, which was substituted into the standard curve in step 5 to calculate the content of pollutants in the water-milled glutinous rice flour sample.

[0021] Preferably, the concentration of the HAuCl4 solution in step 1 (1) is 0.05M, the concentration of the CTAC solution is 0.1M, and the concentration of the NaBH4 solution is 0.01M, wherein the dosage relationship of the HAuCl4 solution, the CTAC solution and the NaBH4 solution is 25μL:4.7mL:300μL, and the storage period at room temperature is 1-2 hours.

[0022] The amount of ultrapure water, CTAC solution, HAuCl4 solution, and NaI solution in step (2) (a) is 8 mL: 1.6 mL: 40 μL: 15 μL, wherein the concentration of the CTAC solution is 0.1 M, the concentration of the HAuCl4 solution is 0.05 M, and the concentration of the NaI solution is 0.01 M;

[0023] The dosage of the HAuCl4 solution, CTAC solution, and NaI solution in step (2) (b) is 500 μL:40 mL:300 μL, wherein the concentration of the CTAC solution is 0.05 M, the concentration of the HAuCl4 solution is 0.05 M, and the concentration of the NaI solution is 0.01 M;

[0024] In step (2) (c), the ratio of the growth solution 1 to the ascorbic acid solution is 10 mL:40 μL; the ratio of the growth solution 2 to the ascorbic acid solution is 40 mL:400 μL; the concentration of the ascorbic acid solution is 0.1 M; the concentration of the CTAC solution is 0.1 M; and the storage time at room temperature is 2 hours;

[0025] The dosage relationship of the diluent and the mixed solution 1 is 100 μL:10 mL; the dosage relationship of the mixed solution 3 and the mixed solution 2 is 3.2 mL:40 mL.

[0026] Preferably, the concentration of the CTAC solution in step (3) is 20-30 wt%; the CTAC solution and the AuNT S The volume ratio of crude liquid is 1:8, and the purification time is 12-24h.

[0027] Preferably, in step 2, the mass ratio of the polydimethylsiloxane to the curing agent is 10:1, the curing and drying temperature is 80° C., the curing time is 10-12 hours, and the curing agent includes dibutyl phthalate; wherein the thickness of the pure PDMS film is 0.5-1 mm.

[0028] Preferably, in step 3, the concentration of the polyacrylic acid solution is 5-15 wt %; the immersion and incubation temperature is 15-20° C., and the immersion time is 10-20 min.

[0029] Preferably, in step 4, the incubation time is 12-24 hours.

[0030] Preferably, in step 5, the concentration range of the pollutant standard solution is 10-10 -4 μg / mL, the pollutant is chloramphenicol (CAP); the certain temperature condition is 30-60°C, and the incubation time is 40-60min.

[0031] Preferably, in step six, the ratio of the water-ground glutinous rice flour to deionized water is 1 g:10 mL; the certain temperature condition is 30-60° C., and the incubation time is 40-60 min.

[0032] Compared with existing detection technologies, the present invention has the following beneficial effects:

[0033] 1. The present invention prepares a flexible transparent PDMS film by spin coating, and combines it with AuNTs nanomaterials through interfacial deposition, surface modification, nanoimprinting and other technologies to prepare a high-performance flexible SERS sensor, which is applied to the rapid SERS sensing detection of pollutants in water-ground glutinous rice flour.

[0034] 2. The AuNTs prepared in the present invention have an edge length of 50 to 150 nm and a regular triangular morphology. Compared with spherical or smoother nanoparticles, the sharp-tipped AuNTs have a wider localized surface plasmon resonance (LSPR) band. The unique optical and plasmon properties give them excellent SERS sensing performance, a more significant enhancement effect, and are more suitable for establishing an optical sensing SERS platform.

[0035] 3. The flexible substrate used in the present invention has good flexibility and optical transparency, can fully contact irregular surfaces, and is conducive to the in situ detection of target analytes; it is inexpensive, easy to make, and can be preserved for a long time. It can be used as a high-performance portable SERS solid-phase sensor for rapid on-site detection of typical pollutants in water-ground glutinous rice flour. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Transmission electron microscopy image of AuNTs.

[0037] Figure 2 Ultraviolet absorption spectra of PDMS and AuNTs@PDMS.

[0038] Figure 3 Fourier mid-infrared diffraction patterns of PDMS, AuNTs and AuNTs@PDMS.

[0039] Figure 4 This is the result diagram of the pollutant prediction model in water-ground glutinous rice flour of the AuNTs@PDMS flexible SERS sensor of the present invention. DETAILED DESCRIPTION

[0040] Exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0041] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0042] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0043] Example 1:

[0044] Step 1, preparation of gold nanotriangles (AuNTs) (preparation of AuNTs by a two-step seed growth method):

[0045] (1) Preparation of gold seeds: First, 25 μL of HAuCl4 (0.05 M) was added to 4.7 mL of CTAC solution (0.1 M). 300 μL of freshly prepared 0°C NaBH4 solution (0.01 M) was added to the above solution with vigorous stirring. The resulting mixed solution was stored at room temperature for 2 h to obtain the gold seed solution.

[0046] (2) Preparation of growth solution:

[0047] CTAC solution (1.6 mL, 0.1 M) was added to 8 mL of ultrapure water, followed by HAuCl4 solution (40 μL, 0.05 M) and NaI solution (15 μL, 0.01 M), and mixed well. The resulting solution was designated as growth solution 1.

[0048] HAuCl4 solution (500 μL, 0.05 M) was added to CTAC solution (40 mL, 0.05 M), and then NaI solution (300 μL, 0.01 M) was added. The resulting solution was designated as growth solution 2;

[0049] The gold seed solution prepared in step (1) was diluted 10-fold in a CTAC solution (0.1 M) to obtain a dilution solution; subsequently, 40 μL of an ascorbic acid solution (0.1 M) was added to 10 mL of the growth solution 1, and the mixture was stirred until the solution became completely transparent to obtain a mixed solution 1; 400 μL of an ascorbic acid solution (0.1 M) was added to 40 mL of the growth solution 2, and the mixture was stirred until the solution became completely transparent to obtain a mixed solution 2;

[0050] 100 μL of the diluent was added to 10 mL of mixed solution 1, and the resulting solution after stirring was recorded as mixed solution 3; 3.2 mL of mixed solution 3 was then mixed with 40 mL of mixed solution 2, and the resulting solution was stored at room temperature for 2 hours to obtain a crude AuNTs solution;

[0051] (3) AuNTs purification: Finally, 5 mL of CTAC (25 wt %) solution was added to 40 mL of the crude AuNTs solution and purified at room temperature for 24 h to obtain a gold nanotriangle (AuNTs) solution;

[0052] Figure 1 This is a transmission electron microscope image of AuNTs. The prepared AuNTs have an edge length of 50 to 150 nm, a regular triangular morphology, and good dispersion. Compared with spherical or smoother nanoparticles, AuNTs with sharp tips have wider localized surface plasmon resonance (LSPRs) bands.

[0053] Step 2: Curing of polymethoxysilane (PDMS) flexible film:

[0054] 3 g of polydimethylsiloxane and 0.3 g of dibutyl phthalate were weighed and mixed and stirred to obtain a mixture; the mixture was poured into a glass mold and placed in an oven at 80° C. and dried for 12 h to obtain a solidified pure PDMS film.

[0055] Step 3: Carboxylation modification of PDMS flexible film:

[0056] The PDMS film was immersed in 6 mL of polyacrylic acid (PAA) (5-15 wt%) solution and incubated for 10 min, after which the excess PAA was removed. The PDMS film was removed and carefully rinsed with ultrapure water, and finally dried with nitrogen gas to obtain a carboxyl-functionalized PDMS film.

[0057] Step 4: AuNTs@PDMS flexible SERS sensor coupling (preparation of AuNTs@PDMS SERS flexible sensor using interfacial self-assembly method):

[0058] First, the gold nanotriangle (AuNTs) solution obtained in step 1 was concentrated 10 times to obtain a concentrated AuNTs solution. The carboxyl-functionalized PDMS film prepared in step 3 was immersed in the concentrated AuNTs solution and incubated for 24 hours. After incubation, the film was washed with ultrapure water and dried with nitrogen to obtain an AuNTs@PDMS film.

[0059] Figure 2 The ultraviolet absorption spectra of PDMS and AuNTs@PDMS are as follows. As can be seen from the figure, the local surface plasmon resonance (LSPR) value of AuNTs is 630-740nm. The prepared PDMS film is a transparent colloid, showing good uniformity and flexibility, and the AuNTs@PDMS film is blue-purple.

[0060] Figure 3 is the Fourier mid-infrared diffraction pattern of PDMS, AuNTs and AuNTs@PDMS; Figure 3(a) shows the FTIR spectrum of PDMS, 786 cm -1 The peak at 1007 cm is attributed to the stretching vibration of Si-CH3. -1 and 1257cm -1 The peaks at are caused by the stretching vibrations of Si-O-Si and Si-OH, respectively. FT-IR spectrum of AuNTs Figure 3 As shown in (b), 1613cm -1 The characteristic peaks correspond to CN vibrations, which are caused by the surfactant residues of CTAC. Figure 3 (c) shows that when PDMS is carboxylated and coupled with AuNTs, the -1 and 1719cm -1 There are two new characteristic peaks at 1719cm -1 The characteristic peak at 1613 cm is due to the asymmetric stretching vibration of the carboxyl group (-COOH) of the PAA ligand. This phenomenon indicates that the carboxyl group from the ligand exchange has been successfully modified on the PDMS surface, resulting in negatively charged PDMS. -1 The unique transmission peak at is attributed to the stretching vibration of CN, indicating that AuNTs have been successfully coupled to PDMS.

[0061] Step 5: Construction of AuNTs@PDMS flexible SERS sensing system:

[0062] First, prepare different concentrations of chloramphenicol (CAP) standard solutions (10, 10 -1 , 10 -2 , 10 -3 , 10 -4 The AuNTs@PDMS film was immersed in CAP standard solutions of different concentrations and incubated in a 40°C oven for 60 min. After incubation, the AuNTs@PDMS film was taken out and the 200-2000 cm -1 The SERS spectra within the range were plotted, and the CAP concentration-related standard curve was drawn according to the SERS intensity signal characteristic values ​​corresponding to the CAP standard solutions with different concentrations.

[0063] Step 6: Detection of chloramphenicol (CAP) in water-milled glutinous rice flour:

[0064] Weigh 1 g of water-ground glutinous rice flour, add 1 mL of CAP standard solution and 9 mL of deionized water, stir evenly to form a homogenate, centrifuge, and collect the supernatant to obtain a sample solution. Measure the SERS intensity signal characteristic value of the sample solution, and calculate the chloramphenicol CAP content in the water-ground glutinous rice flour sample based on the chloramphenicol detection standard curve obtained in step 5.

[0065] Figure 4The results of the pollutant prediction model of the AuNTs@PDMS flexible SERS sensor in water-ground glutinous rice flour of the present invention are shown in the figure; the constructed method achieves 10 -4 Rapid quantitative detection of CAP in the range of μg / mL-10μg / mL, with a predicted correlation coefficient (Rp=0.9802) and a minimum root mean square error of prediction (RMSEP=0.348μg / mL).

[0066] Note: The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although this specification has described the present invention in detail with reference to the above embodiments, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field, all improvements to the technical solutions that do not depart from the spirit and scope of the present invention, should be included in the scope of the claims of the present invention.

Claims

1. An intelligent detection method for pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor, characterized in that: The following steps are involved: Step 1: Preparation of gold nanotriangles; (1) Preparation of gold seed solution: First, HAuCl4 solution was added to CTAC solution, and then NaBH4 solution was added under stirring. The resulting mixed solution was stored at room temperature for a period of time to obtain the gold seed solution; (2) Preparation of growth medium: (a) CTAC solution was added to ultrapure water, followed by HAuCl4 solution and NaI solution, and the mixture was mixed thoroughly. The resulting solution was designated as growth solution 1. (b) HAuCl4 solution was added to CTAC solution, and then NaI solution was added and mixed evenly. The resulting solution was recorded as growth solution 2. (c) diluting the gold seed solution prepared in step (1) by 8-12 times with CTAC solution to obtain a dilution solution; then, adding ascorbic acid solution to growth solution 1 and growth solution 2, respectively, and stirring until the solutions are completely transparent to obtain mixed solutions 1 and mixed solution 2; adding the dilution solution to mixed solution 1, and stirring to obtain a solution obtained as mixed solution 3; then mixing mixed solution 3 with mixed solution 2, and storing the obtained solution at room temperature for a period of time to obtain a crude AuNTs solution; (3) AuNTs purification: CTAC solution was added to the crude AuNTs solution and purified at room temperature. After purification, a gold nanotriangle solution was obtained, which was recorded as AuNTs solution. The prepared AuNTs have an edge length of 50-150 nm and a regular triangle morphology; Step 2: Mixing polydimethylsiloxane and a curing agent to obtain a mixture; then pouring the mixture into a mold for curing and drying to obtain a cured pure PDMS film; the mass ratio of the polydimethylsiloxane to the curing agent is 10:1, the curing and drying temperature is 80°C, and the curing time is 10-12 hours. The curing agent includes dibutyl phthalate; wherein the thickness of the pure PDMS film is 0.5-1 mm; Step 3: Immerse the pure PDMS film prepared in step 2 in a polyacrylic acid solution. After soaking and incubating, take out the pure PDMS film and wash it with ultrapure water. After washing, dry it with nitrogen to obtain a carboxyl-functionalized PDMS film. Step 4: First, the gold nanotriangle solution obtained in step 1 is concentrated by 1-10 times to obtain a concentrated AuNTs solution, and then the carboxyl-functionalized PDMS film prepared in step 3 is immersed in the concentrated AuNTs solution for incubation. After incubation, the film is washed with ultrapure water and dried with nitrogen to obtain an AuNTs@PDMS film; Step 5: Prepare pollutant standard solutions of different concentrations, then immerse the AuNTs@PDMS film prepared in step 4 in the pollutant standard solutions of different concentrations, incubate at 30-60°C for 40-60 min, take out the AuNTs@PDMS film after incubation, and collect 200-2000 cm -1 The SERS spectrum in the range of 10-10 is plotted according to the SERS intensity signal characteristic values ​​corresponding to the pollutant standard solution with different concentrations. -4 μg / mL, the contaminant was chloramphenicol; Step 6: Detection of pollutants in water-ground glutinous rice flour: Take water-ground glutinous rice flour, add deionized water, stir evenly and centrifuge, take the supernatant to obtain the sample solution; then immerse the AuNTs@PDMS film prepared in step 4 in the sample solution and incubate it at a certain temperature. After incubation, take out the AuNTs@PDMS film and collect 200~2000 cm -1 The SERS spectrum within the range was obtained to obtain the SERS intensity signal characteristic value, which was substituted into the standard curve in step 5 to calculate the content of pollutants in the water-milled glutinous rice flour sample.

2. The method for intelligent detection of pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor according to claim 1, characterized in that: In step 1 (1), the concentration of the HAuCl4 solution is 0.05 M, the concentration of the CTAC solution is 0.1 M, and the concentration of the NaBH4 solution is 0.01 M. The dosage of the HAuCl4 solution, CTAC solution, and NaBH4 solution is 25 µL: 4.7 mL: 300 µL, and the solution is stored at room temperature for 1-2 hours.

3. The method for intelligent detection of pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor according to claim 1, characterized in that: The amount of ultrapure water, CTAC solution, HAuCl4 solution, and NaI solution used in step (2) (a) is 8 mL: 1.6 mL: 40 µL: 15 µL, wherein the concentration of CTAC solution is 0.1 M, the concentration of HAuCl4 solution is 0.05 M, and the concentration of NaI solution is 0.01 M; The dosage of the HAuCl4 solution, CTAC solution, and NaI solution in step (2) (b) is 500 µL: 40 mL: 300 µL, wherein the concentration of the CTAC solution is 0.05 M, the concentration of the HAuCl4 solution is 0.05 M, and the concentration of the NaI solution is 0.01 M; In step (2) (c), the dosage ratio of the growth solution 1 and the ascorbic acid solution is 10 mL:40 µL; the dosage ratio of the growth solution 2 and the ascorbic acid solution is 40 mL:400 µL; the concentration of the ascorbic acid solution is 0.1 M; the concentration of the CTAC solution is 0.1 M; the storage period at room temperature is 2 hours; the dosage ratio of the diluent and the mixed solution 1 is 100 µL:10 mL; the dosage ratio of the mixed solution 3 and the mixed solution 2 is 3.2 mL:40 mL.

4. The method for intelligent detection of pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor according to claim 1, characterized in that: The concentration of the CTAC solution in step 1 (3) is 20-30 wt%; the CTAC solution and the AuNT S The volume ratio of crude liquid is 1:8, and the purification time is 12-24h.

5. The method for intelligent detection of pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor according to claim 1, characterized in that: In step 3, the concentration of the polyacrylic acid solution is 5-15 wt %; the immersion incubation temperature is 15-20° C., and the immersion time is 10-20 min.

6. The method for intelligent detection of pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor according to claim 1, characterized in that: In step 4, the incubation time is 12-24 h.

7. The method for intelligent detection of pollutants in water-ground glutinous rice flour based on AuNTs@PDMS flexible SERS sensor according to claim 1, characterized in that: In step six, the ratio of the water-ground glutinous rice flour to deionized water is 1 g:10 mL; the certain temperature condition is 30-60° C., and the incubation time is 40-60 min.

Images