Résumé
Based on signal amplification strategy of dendritic mesoporous silica nanospheres loaded with CdSe/ZnS quantum dots (DMSN@QDs), an ultrasensitive electrochemiluminescence (ECL) immunosensor with magnetic separation was constructed for the detection of SARS-CoV-2 nucleocapsid protein (NP). DMSN, a mesoporous material with abundant radial pores, large specific surface area and high porosity, can increase the loading capacity of QDs and hinder their aggregation as the nanocarrier. DMSN@QDs with good ECL efficiency were used as signal labels to construct a sandwich immunosensor. The designed ECL immunosensor displayed a good linear relationship for NP concentrations ranging from 0.005 ng mL(-1) to 50 ng mL(-1), with a limit of detection of 3.33 pg mL(-1). The ECL immunosensor was successfully applied to detect NP in human serum samples with satisfactory recovery. This strategy provided a new method for detecting NP and expanded the application field of DMSN.
Résumé
With the rapid spread and proliferation of Coronavirus disease 2019 (COVID-19) worldwide, highly pathogenic severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) seriously threatens human life and health. The rapid and accurate abilities to detect SARS-CoV-2 have become the key to prevent and control COVID-19. Electrochemical sensors have shown broad application prospects in biological detection because of the advantages of high sensitivity, specificity, and short time-consuming. This review summarizes the application of electrochemical biosensors in detecting SARS-CoV-2 and discusses prospects for developing direction in this field.