Construction of histamine aptamer sensor based on Au NPs nanozyme for ultrasensitive SERS detection of histamine

The activity of nanozymes is dependent on their surface for catalysis, and bioconjugation or adsorption of DNA aptamers will promote their activity. This paper aims to develop a novel aptamer sensor, for rapid, sensitive and specific detection of histamine. The design of the aptamer biosensor is based on the adsorption of histamine aptamers onto the surface of Au NPs by bioconjugation, which promotes the peroxidase activity of the nanozymes. Since histamine is strongly selective and specific for histamine aptamers, the histamine aptamer can be detached from the surface of Au NPs and bound to histamine, during which the catalytic activity of the nanozymes falls back due to the detachment of the histamine aptamer, which can be quantitative analysis by the TMB-H2O2 system. The decrease in enzyme catalytic activity became larger with increasing histamine concentration, with a good linear correlation. Finally, the histamine aptamer biosensor was constructed, which has the advantages of ultrasensitive, high-accuracy, and wide linear range. The linear range and detection limit are 10(-11)similar to 10(-3) M and 1.22 x 10(-12) M, respectively. With reference to this aptamer sensor design, this approach can also be extended to other schemes where the aptamer is combined with Au NPs as a way to detect the corresponding molecules.