Suppression of Protein Adsorption at Glassy Carbon Electrodes Covalently Modified with Tetraethylene Glycol Diamine

Adsorption of high molecular weight species on electrode surfaces can complicate the application of voltammetric techniques to clinical and environmental samples. The performance of tetraethylene glycol diamine as a protective electrode coating has been examined. Glassy carbon electrodes were covalently modified with the diamine via an electrochemically assisted reaction. The voltammetric response of ferrocenemonocarboxylic acid (FCA) at unmodified and modified electrodes in the presence and absence of bovine serum albumin (BSA), lysozyme and ribonuclease (RNase) was used to monitor surface fouling by protein adsorption. Modified electrodes which retained very high sensitivity for FCA oxidation also exhibited excellent resistance to adsorption of all three proteins.