Construction of a triglyceride amperometric biosensor based on chitosan–ZnO nanocomposite film

• Published in: International journal of biological macromolecules Vol. 49; no. 4; pp. 707 - 715
• Main Authors: Narang, Jagriti, Pundir, C.S.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2011
• Subjects: Amperometric biosensor; Biosensing Techniques - methods; Biosensors; blood serum; chitosan; Chitosan - chemistry; detection limit; Dielectric Spectroscopy; Electric Impedance; Electrochemical Techniques - methods; Electrodes; electrons; Enzyme Stability; Enzymes; Female; films (materials); Glycerol; Glycerol kinase; Glycerol Kinase - metabolism; Glycerol-3-phosphate oxidase; Glycerolphosphate Dehydrogenase - metabolism; half life; Humans; Hydrogen peroxide; Hypertriglyceridemia; Kinase; Lipase; Macromolecules; Male; nanocomposites; Nanocomposites - chemistry; Nanocomposites - ultrastructure; nanoparticles; people; pH effects; scanning electron microscopes; Scanning electron microscopy; Shelf life; silver chloride; Spectroscopy; Spectroscopy, Fourier Transform Infrared; storage quality; Substrate Specificity; temperature; Temperature effects; Triacylglycerol lipase; Triglyceride; Triglycerides; Triglycerides - blood; triolein; Triolein - analysis; X-Ray Diffraction; zinc oxide; Zinc Oxide - chemistry; ZnONPs; ZnONPs; Glycerol-3-phosphate oxidase; Kinase; Glycerol; Amperometric biosensor; Triglyceride; Lipase
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2011.07.001

A method is described for construction of a novel amperometric triglyceride (TG) biosensor based on covalent co-immobilization of lipase, glycerol kinase (GK) and glycerol-3-phosphate oxidase (GPO) onto chitosan (CHIT) and zinc oxide nanoparticles (ZnONPs) composite film deposited on the surface of Pt electrode. The enzymes–ZnONPs–CHIT composite was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The sensor showed optimum response within 6s at pH 7.5 and temperature of 35°C. The sensor measures current due to electrons generated at 0.4V against Ag/AgCl from H2O2, which is produced from triolein by co-immobilized enzymes. A linear relationship was obtained between a wide triolein concentration range (50–650mg/dl) and current (mA) under optimum conditions. The biosensor showed high sensitivity, low detection limit (20mg/dl) and good storage stability (half-life of 7 months at 4°C). The biosensor was unaffected modified by a number of serum substances at their physiological concentrations. The biosensor was evaluated and employed for determination of TG in sera in apparently healthy subjects and persons suffering from hypertriglyceridemia.