Electrochemical recognition for saccharide by boronic acid carrying self-assembled monolayer
Thiol compound (TGA-PBA) that carried boronic acid groups at its ends was prepared by coupling of 3-amino-phenylboronic acid (PBA) with mercaptoacetic acid (TGA). The compound obtained formed a self-assembled monolayer on gold electrode as proved by X-ray photoelectron spectra (XPS) and cyclic voltammetry (CV). The self-assembled monolayer TGA-PBA/Au showed the strong binding affinity toward sacharide with the binding constant of 1.94×10~(8)L/mol to D-galactose, and hindered the electron transfer of [Fe(CN)_(6)]~(3-/4-) marker on the electrode surface. A high sensitive electrochemical sensor for saccharide was developed based on this principle.