Miniaturized label-free impedimetric immunosensor for analysis of aflatoxin B1 in peanut

A highly sensitive and selective label-free impedimetric immunosensor based on silver (Ag) wire electrode for the detection aflatoxin B1 (AFB1) in peanut is presented. The sensor was constructed by functionalizing Ag wire coupled with polyclonal antibodies of AFB1 through self assembled monolayers. The antigen-antibody interaction was analyzed by measuring impedance in the frequency range (1–100 KHz) at 5mV applied ac potential in a 384 micro well plate with assay volume 105μL. A working range (0.01–100pg/mL) for AFB1 was obtained with 20min analysis time with limit of detection 0.01pg/mL. The obtained SD and R
²
values were 0.16 and 0.95 respectively.