Acetylcholinesterase-based conductometric biosensor for determination of aflatoxin B1

The theoretical and experimental studies were carried out, which resulted in the development of acetylcholinesterase-based conductometric biosensor for determination of aflatoxin B1. We established a linear range of substrate measurement (0.25–1 mM) and optimal concentration of acetylcholine for inhibitory analysis (1 mM). The sensitivity of developed biosensor to aflatoxin B1 was tested, the calibration curve was plotted for the dependence of residual activity of the acetylcholinesterase-based bioselective element on the toxin concentration. Detection limit of aflatoxin B1 was 0.05 μg/ml. It was shown that the developed biosensor was characterized by high signal reproducibility of direct determination of the main substrate as well as of the inhibitory analysis of aflatoxin B1 (the error of detection was no more than 7%).