A highly sensitive electrogenerated chemiluminescence (ECL) method for the determination of ferrocenemonocarboxylic acid (FMC) was developed. It was found that the ECL intensity of luminol-H2O2-FMC system could be greatly enhanced at a graphite electrode (GE) modified with gold nanoparticles. The test conditions including the modified amount of gold nanoparticles on GE, working potential, the concentrations of luminol and hydrogen peroxide were optimized. The integrated ECL intensity at the applied potential of +390 mV (vs. Ag/AgCl, sat. KCl) in 0.10 mol/L carbonate buffer solution (pH 9.2) containing 2.5×10-9 mol/L luminol and 1.0×10-3 mol/L hydrogen peroxide linearly respond to the concentration of FMC in the range from 1.0×10-9 mol/L to 1.0×10-6 mol/L. The detection limit is 7.0×10-10 mol/L (S/N=3). The developed method has a potential application to the ECL immunoassay and DNA hybridization detection based on the FMC label.

electrogenerated chemiluminescence; ferrocenemonocarboxylic acid; gold nanoparticles; luminol