Preparation method of aptamer sensor for pesticide detection

An aptamer sensor and aptamer technology, which is applied in the direction of instruments, measuring devices, scientific instruments, etc., can solve the problems affecting the stability, sensitivity and selectivity of aptamer sensors, and it is difficult to meet low residue and quantitative detection, enzyme inhibition The recovery rate of the method is low, and the effect of promoting the transfer of electrons, wide detection range and high sensitivity is achieved.

Pending Publication Date: 2017-05-31
SHANDONG UNIV OF TECH
View PDF5 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Commonly used rapid detection methods for pesticide residues include enzyme inhibition method and immunosensor method, which can realize rapid on-site detection of organophosphorus pesticides and have good practical value. High, poor repeatability, difficult to meet the requirements of low residue and quantitative detection, etc., the immunosensor is a sensor developed based on the principle of the immune response triggered by the specific combination of antigen and antibody, but the acquisition of the biologically sensitive substance antibody is expensive, and the processing The environment is relatively harsh. Compared with the traditional immunoassay method, the aptasensor has the advantages of strong specificity, fast analysis speed, simple structure, and low cost. The sensitive interface of the aptasensor is the surface of the fixed aptamer to the electrode. , which directly affects the main properties of the aptasensor such as stability, sensitivity and selectivity

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of aptamer sensor for pesticide detection
  • Preparation method of aptamer sensor for pesticide detection
  • Preparation method of aptamer sensor for pesticide detection

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] The preparation of embodiment 1 conductive carbon black-chitosan nanocomposite liquid

[0044] Dissolve chitosan (CS) in 1.0% acetic acid solution, prepare 0.5% CS solution, stir magnetically at room temperature until chitosan is completely dissolved, dissolve 1.0 mg conductive carbon black powder in 1.0 mL of the above CS solution, and ultrasonically Disperse until a uniformly dissolved composite solution is obtained, figure 1 It is the transmission electron microscope image of the conductive carbon black-chitosan composite, A is a low-magnification scanning image, and B is a high-magnification projection image;

Embodiment 2

[0045] Example 2 Preparation of graphene oxide-ferric oxide composite

[0046] Graphene oxide is prepared by the improved Hummers method, and the specific preparation steps are as follows: adding graphite powder to H 2 SO 4 (12mL), K 2 S 2 o 8 (2.5 g), P 2 o 5 (2.5 g) in a mixed solution at 80°C for 4.5 h, then diluted with 0.5 L of water, filtered and washed to remove excess acid, and the resulting pre-product was dried overnight at room temperature, and then the pre-oxidized graphite was added to H 2 SO 4 (120 mL), gradually add KMnO 4 (15 g), the mixture was stirred and reacted at 35°C for 30 min, and reacted at 90°C for 90 min, diluted with 250 mL of water, allowed to boil for 25 min, stirred for another 2 hours, added 0.7 L of water and 20 mL of 30%H 2 o 2 solution to terminate the reaction, the mixture was filtered and rinsed several times with 1:10 dilute hydrochloric acid, and then rinsed with water to neutrality, and then the resulting product was furth...

Embodiment 3

[0047] Example 3 Cleaning, activation and testing of glassy carbon electrodes

[0048] Before modification, the glassy carbon electrode was immersed in hot "piranha" solution (H 2 SO 4 : H 2 o 2 = 3:1) for 15 min, rinsed with water, and then 0.3 µm, 30 nm Al 2 o 3 Polish the slurry on the suede to a mirror surface, wash with deionized water after polishing to remove surface dirt, and then use 6 mol / L HNO 3 , absolute ethanol, and deionized water were ultrasonically cleaned for 5 min, and dried under nitrogen atmosphere.

[0049] Activation of the glassy carbon electrode: After thorough cleaning, the electrode was heated at 0.5 mol / L H 2 SO 4 The solution was activated by cyclic voltammetry, the scanning range was 1.0 V~-1.0 V, and the scanning was repeated until a stable cyclic voltammetry was achieved.

[0050] Test of pretreated glassy carbon electrodes: in the presence of 1×10 -3 mol / L K 3 Fe(CN) 6 0.20 mol / L KNO 3 Run the cyclic voltammetry curve in the solut...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
recovery rateaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of an aptamer sensor for pesticide detection, and belongs to the technical field of safety detection of agricultural products. The preparation method provided by the invention comprises the following steps: drop-coating carbon black-chitosan compound liquid on a surface of a bare glassy carbon electrode after cleaning, activation and performance testing; then, modifying with a graphene oxide-iron oxide compound; immobilizing a pesticide aptamer on the modified electrode; and finally, closing with bovine serum albumin. The aptamer sensor prepared in the invention has characteristics of high sensitivity, low cost, high detection speed, good stability and high sample recovery rate, has a detection limit of 0.033 ng/mL, a linear range of 0.1-105 ng/mL, a recovery rate of 96.0-106.0%, and is suitable for rapid detection of pesticide residues in fruits and vegetables.

Description

technical field [0001] The invention relates to a preparation method of an aptamer sensor for detecting pesticides, belonging to the technical field of agricultural product safety detection. [0002] technical background [0003] With the continuous improvement of people's living standards in our country, the quality and safety of agricultural products has attracted more and more attention, especially the problem of pesticide residues in fruits and vegetables has become the focus of public attention. Commonly used pesticides such as chlorpyrifos, parathion, and profenofos have certain The systemic nature of pesticides can be transferred to the human body through the enrichment of the food chain, and has a potential carcinogenic effect on the human body. Therefore, pesticides have always been an important item in environmental and food safety testing. Strengthening the detection of pesticide residues in agricultural products is important for protecting the ecological environmen...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N27/327
CPCG01N27/3277
Inventor 孙霞焦艳翠郭业民
Owner SHANDONG UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products