Label-Free Electrochemical Test of Protease Interaction with a Peptide Substrate Modified Gold Electrode

Efficient deposition of biomolecules on the surface, maintaining their full activity and stability, is a most significant factor in biosensor construction. For this reason, more research focused development electrochemical biosensors that have ability to electrically detect adsorbed molecules electrode surface with high selectivity sensitivity. The presented aims develop an efficient methodology allows quantification processes related evaluation enzyme (proprotein convertase) using methods. In study we used impedance spectroscopy investigate immobilization peptide substrate (Arg-Val-Arg-Arg) modified 11-mercaptoundecanoic acid gold electrode. Both synthesis as well characteristics obtained materials been described. Experimental conditions, including concentration immobilization, modification time, linker, presence additional blocking groups optimized. main advantages described method it makes possible observe substrate–enzyme interaction without need use fluorescent labels. This also observation at very low concentration. these factors make new technique competitive standard spectrofluorimetric method.