Polyaniline Based Electrochemical Biosensor for α-Fetoprotein Detection Using Bio-functionalized Nanoparticles as Detection Probe

Composite of polyaniline, bovine serum albumin and silver nanoparticles was used as the enriched immobilization matrix (EIM)-cum-electrode material for detection of liver cancer biomarker, alpha-fetoprotein (AFP) in blood serum. In the sandwich biosensor, signal amplification was bestowed by EIM and detection probe. EIM entrapped large amount of capture antibody due to its higher surface area and amine-rich nature, whereas detection probe enhanced the electrochemical signal during its binding with AFP. Biosensor exhibited excellent sensitivity, selectivity, reproducibility with a detection limit of 4.7 pg/mL. The amplification strategy adopted herein has potential for clinical detection of cancer biomarkers in point-of-care diagnostics.