Synthesis of Gold Coated Magnetic Microparticles and Their Application for Electrochemical Glucose Sensing by the Enzymatically Precipitated Prussian Blue

An enzyme stimulated deposition of prussian blue onto the gold-coated magnetic microparticles is described. We propose to synthesize the continuous outer gold layer on the magnetic particle for a gold working electrode and its superparamagnetic property. In-depth characterization of the gold shell formation was studied with scanning electron microscopy, energy-dispersive X-ray spectroscopy, cyclic voltammetry. The gold-coated magnetic microparticles offered adhesive layer for the immobilization of glucose oxidase catalyzing the generation of prussian blue in the presence of glucose. The assembled prussian blue on the gold shell surfaces was detected with electrochemical measurements depending on the glucose concentration. With accomplishing the linear response range from 0.2 nnM to 10 mM of glucose, this approach successfully proposed the applicability of the magnetic core-gold shell structures to the electrochemical bioassay area.