Enhanced electrochemiluminescence of peroxydisulfate by electrodeposited Au nanoparticles and its biosensing application via integrating biocatalytic precipitation using self-assembly bi-enzymes

The enhanced electrochemiluminescence (ECL) of peroxydisulfate was observed on Au nanoparticles (Au NPs) electrodeposited on ITO electrode. Glucose oxidase (GOD) and horseradish peroxidase (HRP) were self-assembled upon Au NPs. Thus, a “signal-off” ECL biosensor to detect glucose by integrating biocatalytic precipitation (BCP) has been achieved. The morphologies of Au NPs and GOD-HRP/Au NPs modified ITO were characterized by scanning electron microscopy (SEM). The electrochemical behaviors of the Au NPs/ITO, GOD-HRP/Au NPs/ITO and BCP/GOD-HRP/Au NPs/ITO were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The resulted biosensor combined the ECL amplification by Au NPs with the self-assembled bi-enzymes integrated BCP system presents a wide linear range from 8.0 × 10−7 to 2.0 × 10−2 M, and with a high sensitivity of 1.0 × 10−7 M and good stability for glucose detection.