Development of an immuno-electrochemical glass carbon electrode sensor based on graphene oxide/gold nanocomposite and antibody for the detection of patulin

•A rabbit anti-patulin-BSA IgG was developed for the detection of fungal toxin patulin.•The rabbit anti-patulin-BSA IgG was applied to a glass carbon electrode sensor confined with graphene oxide.•The developed sensor has linearity with concentration of patulin.•The sensor could detect as low as 5 µg/L of patulin in a few minutes. The presence of fungal-produced patulin in foods poses a high health risk to people because it can cause neurologic and gastrointestinal illnesses. A glass carbon electrode (GCE) sensor was developed for the rapid and sensitive detection of patulin. Anti-patulin-BSA IgG of a rabbit was produced and immobilised on a GCE coated with a graphene oxide/gold nanocomposite. The mycotoxin patulin in the samples could be captured by the anti-patulin-BSA IgG on the surface of the GCE sensor. The spatial hindrance effect of IgG on the GCE sensor was reduced by the reaction between IgG and patulin, resulting in a decrease in the electron transfer resistance. The current changes in the immobilised anti-patulin-BSA IgG GCE sensor exhibited a linear relationship with patulin concentration and facilitated the sensitive detection of patulin. This immuno-electrochemical GCE sensor could rapidly detect patulin in less than 1 min with a detection limit of 5 µg/L.