Conductometric enzyme biosensor for patulin determination

•Novel biosensor was proposed for determination of patulin inhibitory potency.•Biosensor principle was based on urease inhibition by patulin.•The proposed biosensor was optimized for analysis of patulin inhibitory potency.•The developed biosensor was characterized by a high sensitivity to patulin.•Selectivity of the developed biosensor to different groups of toxins was analyzed. The research is aimed at the development and optimization of conductometric biosensor for determination of the inhibitory potency of patulin and verification of its feasibility after reactivation. A differential pair of gold interdigitated electrodes deposited on the sital substrate was used as the conductometric transducer of a signal. Urease, co-immobilized with bovine serum albumin by cross-linking with glutaraldehyde on the transducer surface, served as a bioselective membrane. The proposed biosensor was optimized for determination of the inhibitory potency of patulin. It was characterized by quite high sensitivity to patulin, good selectivity and signal reproducibility. A multiple restoration of the biosensor activity after use was rendered possible by a cysteine treatment. It was also tested the sensitivity of the biosensor developed to other groups of toxic substances. In the future, the proposed biosensor can be successfully used for the patulin analysis in real samples.