Electrochemical and Spectroscopic Characterization of Glucose Oxidase Immobilized in Polyvinyl Alcohol and Applications in Glucose Detection
A simple and novel amperometric biosensor for glucose detection is proposed. It is based on the immobilization of glucose oxidase in a poly(vinyl alcol) matrix drop casted on a platinum electrode surface (Pt/GOx-PVA). The composite material GOx-PVA has been characterized by UV-vis spectroscopy to verify the preservation of enzyme structural integrity and of the enzymatic activity in PVA membrane. X-ray Photoelectron Spectroscopy (XPS) characterization revealed a homogeneous film deposited on Pt whose structure is preserved under operative conditions. Glucose was determined in the absence of a mediator used to transfer electrons between the electrode and the enzyme. Amperometric characterization has been performed at ?400 mV by using pulsed amperometric detection (PAD). Under the selected optimal conditions, the biosensor showed wide dynamic range (0.1–37 mM) yielding a low limit of detection (10 ?M). Biosensor performance was satisfactory also in terms of repeatability, reproducibility and anti-interference ability.
KeywordsWide Dynamic Range Amperometric Response Glucose Biosensor Pulse Amperometric Detection Glucose Detection