CN-121978094-A - Test paper for detecting carbamate and organophosphorus pesticides, and preparation method and application thereof

CN121978094ACN 121978094 ACN121978094 ACN 121978094ACN-121978094-A

Abstract

The invention relates to the technical field of detection test paper, and particularly discloses test paper for detecting carbamate and organophosphorus pesticides, and a preparation method and application thereof. The test paper comprises a PVC substrate, and a sample pad, a nitrocellulose membrane and a water absorption pad which are sequentially laminated, wherein the nitrocellulose membrane is coated with a detection line formed by manganese dioxide nanoneedles wrapped by bovine serum albumin. The test paper provided by the invention can realize semi-quantitative detection of carbamate and organophosphorus pesticides by counting the disappeared quantity of the detection lines, has the advantages of simplicity and convenience in operation, low cost, convenience in carrying, visual result interpretation, strong anti-interference capability and the like, and is particularly suitable for on-site rapid screening.

Inventors

CHEN ZIJIAN
MO QIJIE
LIANG QIAN
WANG HONGWU
HUANG AIJUN
CHEN KECHENG
LIN YUNYI
Ye Siliu
WANG QING
ZHONG YINGYING

Assignees

肇庆学院

Dates

Publication Date: 20260505
Application Date: 20260204

Claims (9)

1. The test paper for detecting carbamate and organophosphorus pesticides is characterized by comprising a PVC substrate (4), wherein a sample pad (1), a nitrocellulose membrane (2) and a water absorption pad (3) are sequentially arranged on the PVC substrate (4) from left to right; At least one detection line (201) is arranged on the nitrocellulose membrane (2); The detection line (201) is formed by scribing a manganese dioxide nanoneedle solution wrapped by bovine serum albumin, and the bovine serum albumin and manganese ions on the surface of the manganese dioxide nanoneedle form coordination bonds, so that the bovine serum albumin is wrapped on the surface of the manganese dioxide nanoneedle.
2. The test paper for detecting carbamate and organophosphorus pesticides according to claim 1, wherein the manganese dioxide nanoneedle is gamma-MnO 2 in needle shape and has a length of 5-22 nm.
3. The test paper for detecting carbamate and organophosphorus pesticides according to claim 1, wherein the content of manganese dioxide nanoneedles wrapped by bovine serum albumin in each detection line (201) is 3.0-3.4 μg.
4. The test paper for detecting carbamate and organophosphorus pesticides according to claim 3, wherein the number of the detection lines (201) is 3-5, and the interval between adjacent detection lines (201) is 3.8-4.2 mm.
5. A method for preparing the test paper for detecting carbamate and organophosphorus pesticides according to any one of claims 1 to 4, which is characterized by comprising the following steps: Mixing bovine serum albumin solution, manganese sulfate monohydrate solution and sodium hydroxide solution for reaction to obtain a reaction solution, and sequentially dialyzing and concentrating the reaction solution to obtain a concentrated solution; Diluting the concentrated solution to 4 mg/mL-10 mg/mL to obtain a manganese dioxide nanoneedle solution wrapped by bovine serum albumin, uniformly coating the manganese dioxide nanoneedle solution on a nitrocellulose membrane (2) to form at least one detection line (201), and drying to obtain the nitrocellulose membrane with the detection line; And (3) sticking a nitrocellulose membrane with a detection line to the middle section area of the PVC substrate (4), and then sticking a sample pad (1) and a water absorption pad (3) to the PVC substrate (4) and the two ends of the nitrocellulose membrane (2) respectively to obtain the test paper for detecting carbamate and organophosphorus pesticides.
6. The method for preparing a pesticide for detecting carbamate and organophosphorus according to claim 5, wherein the volume ratio of the bovine serum albumin solution, the manganese sulfate monohydrate solution and the sodium hydroxide solution is 40-60:1.5-2.5:0.5-1; The concentration of the bovine serum albumin solution is 1.2-mg/mL-1.8-mg/mL, the concentration of the manganese sulfate monohydrate solution is 90-mmol/L-110-mmol/L, and the concentration of the sodium hydroxide solution is 0.5-mol/L-1.5-mol/L.
7. The method for preparing pesticides for detecting carbamate and organophosphorus as claimed in claim 5, wherein the reaction time is 50 min-70 min.
8. The method for preparing the pesticide for detecting the carbamate and the organophosphorus according to claim 5, wherein the dialysis is carried out by adopting a dialysis bag with the molecular weight cut-off of 80-100 kDa to dialyze in water for 1-2 days, and the concentration is carried out by adopting an ultrafiltration tube with the molecular weight cut-off of 25-30 kDa.
9. The application of the test paper according to any one of claims 1 to 4 in detecting carbamate and organophosphorus pesticides, which is characterized by comprising the following steps: Mixing a sample to be detected with a phosphate buffer solution, and oscillating to obtain a sample extracting solution; mixing acetylcholinesterase liquid with sample extracting liquid, incubating for reaction, adding iodized thiocholine for continuous reaction, adding iodine liquid for reaction after the reaction is finished, and then adding ascorbic acid solution to obtain sample solution (5); Inserting the sample pad (1) end of the test paper into the sample solution (5), reacting for 5-10 min, observing the color disappearance condition of the detection line (201) on the nitrocellulose membrane (2), and if the color on the detection line (201) does not disappear, indicating that the sample solution (5) contains carbamate and organophosphorus pesticides, and the more the detection line (201) does not disappear, indicating that the sample solution (5) contains higher carbamate and organophosphorus pesticides.

Description

Test paper for detecting carbamate and organophosphorus pesticides, and preparation method and application thereof Technical Field The invention relates to the technical field of detection test paper, in particular to test paper for detecting carbamate and organophosphorus pesticides, and a preparation method and application thereof. Background Carbamate and organophosphorus pesticides are pesticides commonly used in agriculture, and the use ratio of the carbamate and the organophosphorus pesticides is more than 90%, so that the efficient detection of the carbamate and the organophosphorus pesticides is critical to food quality monitoring, and the prior art has significant limitations. The enzyme inhibition method is a traditional rapid detection method of carbamate and organophosphorus pesticides, the method utilizes acetylcholinesterase (AChE) to catalyze iodo-thiocholine (ATChI) to generate thiocholine, the thiocholine reacts with 5,5' -dithiobis (2-nitrobenzoic acid) to generate yellow compounds, when carbamate and organophosphorus pesticides exist in a sample, the activity specificity of the acetylcholinesterase is inhibited, the content of the yellow compounds is reduced, and the inhibition rate of the acetylcholinesterase activity is judged by measuring the content of the yellow compounds by spectrophotometry, so that whether the carbamate and the organophosphorus pesticides exist in the sample is determined. The method is simple to operate, but still needs a color reagent and a carrying spectrophotometer, has high cost and does not have the portability of field detection. Disclosure of Invention The invention provides test paper for detecting carbamate and organophosphorus pesticides, a preparation method and application thereof. When the test paper provided by the invention is used for detecting carbamate and organophosphorus pesticides, mnO 2 in the detection line is reduced into colorless Mn 2+ ions, so that the detection line is changed from brown to colorless visually, and the semi-quantitative analysis of target pesticides can be realized by counting the disappearing quantity of the detection line. The invention provides test paper for detecting carbamate and organophosphorus pesticides, which comprises a PVC substrate, wherein a sample pad, a nitrocellulose membrane and a water absorption pad are sequentially arranged on the PVC substrate from left to right; at least one detection line is arranged on the nitrocellulose membrane; The detection line is formed by scribing a manganese dioxide nanoneedle solution coated with bovine serum albumin, and the bovine serum albumin and manganese ions on the surface of the manganese dioxide nanoneedle form coordination bonds so that the bovine serum albumin is coated on the surface of the manganese dioxide nanoneedle. When the test paper provided by the invention is used for detecting carbamate and organophosphorus pesticides, mnO 2 in the detection line is reduced into colorless Mn 2+ ions, so that the detection line is changed from brown to colorless visually, and the semi-quantitative analysis of target pesticides can be realized by counting the disappearing quantity of the detection line. Further, the manganese dioxide nano needle is gamma-MnO 2 needle-shaped, and the length of the manganese dioxide nano needle is 5-22 nm. Further, the content of the manganese dioxide nanoneedle wrapped by the bovine serum albumin in each detection line is 3.0-3.4 mug. Further, the number of the detection lines is 3-5, and the distance between every two adjacent detection lines is 3.8-4.2 mm. The invention also provides a preparation method of the test paper for detecting the carbamate and the organophosphorus pesticides, which comprises the following steps: Mixing bovine serum albumin solution, manganese sulfate monohydrate solution and sodium hydroxide solution for reaction to obtain a reaction solution, and sequentially dialyzing and concentrating the reaction solution to obtain a concentrated solution; diluting the concentrated solution to 4 mg/mL-10 mg/mL to obtain a manganese dioxide nanoneedle solution wrapped by bovine serum albumin, uniformly coating the manganese dioxide nanoneedle solution on a nitrocellulose membrane to form at least one detection line, and drying to obtain the nitrocellulose membrane with the detection line; And sticking a nitrocellulose membrane with a detection line to the middle section area of the PVC substrate, and sticking a sample pad and a water absorption pad to the PVC substrate and the two ends of the nitrocellulose membrane respectively to obtain the test paper for detecting carbamate and organophosphorus pesticides. Further, the volume ratio of the bovine serum albumin solution, the manganese sulfate monohydrate solution and the sodium hydroxide solution is 40-60:1.5-2.5:0.5-1; The concentration of the bovine serum albumin solution is 1.2-mg/mL-1.8-mg/mL, the concentration of the manganese sulfate monohydrate solution is 90-m