Study Of Electrochemical Immunosensor And Its Application In Food Safety

Electrochemical immunosensor combines the strengths of electrochemical analysis and immunological techniques,which has the advantages of rapid detection,high sensitivity,good specificity and easy operation.The electrochemical immunosensor has been widely used in food safety analysis and clinical medicine,environmental pollutant detection and some other fields in recent years.Literature reviews show that the use of electrochemical immunosensor monitoring of benzo[a]pyrene,aflatoxin B₁ and salbutamol research is relatively rare in food safety analysis.In this paper,We used benzo[a]pyrene,aflatoxin B₁ and salbutamol as the research objects,and chooesd polyamidoamine,chitosan,graphene,1-butyl-3-methylimidazolyl tetrafluoroborate as modified materials to construct three sensitive immunosensor,based on cyclic voltammetry characterization of the immunosensor construction process,through the difference pulse voltammetry to measure the current changes of the interface current after the immune response.The main contents of this paper are as follows:（1）An electrochemical immunosensor for highly sensitive determination of benzo[a]pyrene in food has been constructed by employing 2.0 G polyamidoamine,grapheme and 1-butyl-3-methyl imidazolium tetrafluoroborate composite film to immobilize PAHs antibody on the surface of glassy carbon electrode.Under the optimized experimental parameters,the response current of the immunosensor decreases with the increase of benzo[a]pyrene concentration,and the response current is linear with the concentration of BaP in the range of 0.1～100 ng/mL;Excellent stability and reproducibility of the prepared anti-PAHs/PAMAM/GS/IL/GCE immunosensor were observed in the selected condition.The developed method was applied to the determination of benzo[a]pyrene in peanut and rapeseed oil,and the recovery rate was in94.46%～103.36%.The results were well agreed with those obtained by high performance liquid chromatography method,so it is practicable for rapid determination of benzo[a]pyrene in grain and oil food.（2）An electrochemical immunosensor for rapid determination of aflatoxin B₁ in food has been constructed by employing chitosan,graphene and 1-butyl-3-methyl imidazolium tetrafluoroborate composite film to immobilize aflatoxin B₁ antibody on the surface of glassy carbon electrode.Under the optimized experimental conditions,the peak current of the immunosensor reduced value increased with the increase of the logarithm of the concentration of aflatoxin B₁ in solution,and the reduced value is linear with the logarithm of the concentration of aflatoxin B₁ concentration in the range of 0.1～8.1 ng/mL;Excellent stability and repeatability of the prepared anti-AFB₁/CS/GS/IL/GCE immunosensor were observed in the selected condition.The developed method was applied to the determination of aflatoxin B₁ in peanut and corn oil samples,and the recovery rate was in 95.45%～103.53%.Being more precise and accurate than enzyme linked immunosorbent assay,it is practicable for rapid determination of aflatoxin B₁ in food.（3）An nano immunosensor for rapid determination of salbutamol in food has been constructed by employing polyamidoamine,carboxyl group of multi-walled carbon nanotubes and 1-butyl-3-methyl imidazolium tetrafluoroborate compound material to immobilize salbutamol antibody on the surface of glassy carbon electrode.Under the optimized experimental parameters,the response current of the immunosensor decreases with the increase of salbutamol concentration,and the response current is linear with the concentration of salbutamol in the range of 0.1～25 ng/mL;Excellent specificity,stability and reproducibility of the prepared anti-SAL/PAMAM/MC-COOH/IL/GCE immunosensor were observed in the selected condition.The developed method was applied to the determination of salbutamol in pork and mutton,and the recovery rate was in 95.70%～103.80%.Being more precise and accurate than enzyme linked immunosorbent assay,it is practicable for rapid determination of salbutamol in food.