Electrochemical Methods for the Investigation of Bioaffinity Interactions Based on Gold Nanoparticles Modified Sensors

摘要

Gold nanoparticles (AuNP) stabilized by the synthetic membrane-like compound didodecyldimethylammonium bromide (DDAB) were used for the modification of graphite screen-printed electrodes (SPE). Two different electrochemical approaches based on AuNP modified sensors for the detection of bioaffinity interactions were developed. As a model human cardiac myoglobin-complementary antimyoglobin antibody couple was taken. In the first method AuNP worked as an electrochemical sensing platform: the oxidation of the gold surface (resulted in gold oxide formation) upon polarization served as a basis for analytical response. In the second assay, AuNP served as effective electrocatalysts of Fe3+/Fe2+ electrode reaction of myoglobin. For both assays the same AuNP synthesis and electrodes modification procedures were used.