Development of electrochemical aptasensor based on gold nanorod and its application for detection of aflatoxin B1 in rice and blood serum sample

Aflatoxins are a group of fungal mycotoxins produced mainly by molds, e.g. Aspergillus flavus and Aspergillus parasiticus. Among Aflatoxins, Aflatoxin B1 (AFB1) is the most toxic. Therefore, there is a prompt need for determination of AFB1 in food products. This paper reports an electrochemical aptasensor for accurate determination of AFB1, which was constructed by the using gold nanorod sensing interface and aptamer as specific recognition element. The synthesized gold nanorod was characterized by transmission electron microscopy and the electrochemical behavior of fabricated aptasensor was investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Under optimized conditions the detection limit of proposed aptasensor was 0.3 pM with dynamic range of 1.0 pM – 0.25 nM. This aptasensor represents a remarkable improvement in terms of sensitivity, selectivity, reproducibility and stability when compared to other method for the determination of AFB1. This proposed sensor was successfully applied for the analysis of AFB1 in rice and blood serum samples.