Construction of a portable immunosensor for the sensitive detection of carbendazim in agricultural products using a personal glucose meter

Portable and sensitive detection of carbendazim (CBD) is highly desirable for food safety and environmental protection. Herein, a portable immunosensor for the sensitive detection of CBD is proposed based on alkaline phosphatase (ALP)-labeled and secondary antibody-modified gold nanoparticles (AuNPs). The quantification is based on ALP catalyzing the dephosphorylation of glucose-1-phosphate disodium salt to generate glucose, thus converting the concentration of CBD into glucose, thereby realizing the portable detection of CBD by personal glucose meter. Benefiting from signal amplification strategy that integrates the large specific surface area of AuNPs, the enzymatic reactions of terminal deoxynucleotidyl transferase and ALP, a low detection limit of 0.37 ng/mL for CBD is achieved. When this portable method is used to analyze citrus fruit, canned citrus, and cabbage, good-consistency results are obtained with the UPLC-MS/MS method. The good performance demonstrates the great potential of this portable method for CBD monitoring in resource-poor settings.

Automated summary

A portable immunosensor based on ALP-labeled and secondary antibody-modified AuNPs is proposed for sensitive detection of CBD. The enzymatic reactions and signal amplification strategy involving AuNPs enable a low detection limit of 0.37 ng/mL. Good-consistency results are obtained when using this portable method to analyze citrus fruit, canned citrus, and cabbage, demonstrating its potential for CBD monitoring in resource-poor settings.