1993 Volume 9 Issue 5 Pages 583-587
The adsorption of quaternary ammonium ions, alcohols and FMN (flavin mononucleotide) on the surface of a glassy carbon electrode was examined by the specular reflection method. Reflectivity on the R/R0-E curve of the electrode with 0.1mol dm-3 NaClO4 decreased gradually with increase in applied potential. This decrease can be explained as due to the formation of chemically adsorbed oxygen. With increase in the molecular size of quaternary ammonium ions and alcohols, decrease in R/R0 occurs in a progressively wider potential region at lower concentrations. FMN in oxidized form is adsorbed on the glassy carbon electrode. This method is useful for assessing the adsorption of electroinactive and electroactive substances usually present in HPLC samples or mobile phases.