International Journal of ChemTech Research CODEN (USA): IJCRGG ISSN: 0974-4290 Vol.7, No.2, pp 858-866, 2014-2015 ICONN 2015 [4 th -6 th Feb 2015] International Conference on Nanoscience and Nanotechnology-2015 SRM University, Chennai, India Benzymatic triglyceride biosensor based on electrochemically reduced graphene oxide 1 *Sheetal K Bhardwaj, 2 Ajit K.Mahapatro 1 Tinku Basu 1 1 Amity institute of nanotechnology, Amity University Uttar Pradesh, Noida-201303, India. 2 Department of physics and astrophysics, University of Delhi, Delhi-110007, India. Abstract : Triglycerides (triacylglycerols) estimation is extremely important since its high concentration [normal range in men (40–160 mg/dL) and in women (35–135 mg/dL)] can cause hyperlipidemia 1 . Apart from coronary diseases, hyperlipidemia is useful for diagnosis and treatment of diabetes mellitus, nephrosis, liver obstruction and other diseases involving lipid metabolism of various endocrine disorder 2 . Reduced graphene oxide has recently triggered research interest for electrochemical biosensing applications due to its high electron mobility, excellent electrochemical properties and high surface area. Graphene oxide has been synthesized via modified Hammer's method. A uniform thin film of reduced graphene oxide (RGO) has been electrodeposited using chronoamperometric technique on indium tin oxide(ITO) electrode. The structural and morphological characterization of ERGO/ITO electrode electrodeposited on ITO electrode have been carried out by Field effect scanning electron microscopy,Raman spectroscope, FTIR and cyclic voltammetry to fabricate ERGO/ITO electrode with optimum electronic, chemical and structural properties. Glycerol dehydrogenase (GDH) and Lipase (LIP) have been co-immobilized on ERGO/ITO electrode via carbodiimide chemistry to prepare bio electrode (LIP-GDH/TB/ERGO/ITO) for sensing triglyceride. In this investigation, a novel biochemical path has been developed through potassium ferro/ferri ([Fe(CN) 6 ] 3-/4- ) and toluidine blue in place of NADH which deteriorates biosensor shelf life and causes fouling effect. Response studies have been done using cyclic voltammetry revealing that this fabricated electrode can detect tributyrin in the range of 50- 300mg/dL with high sensitivity and a low value of apparent Michaelis–Menten constant 0.152mM moles indicating high enzyme affinity of bioelectrodes (LIP-GDH/TB/ERGO/ ITO) towards tributyrin. The (LIP-GDH/TB/ERGO/ITO) bioelectrode has been also utilized to estimate triglyceride in serum samples. Introduction Triglyceride (TG), an ester derived from glycerol and three fatty acids molecules is a component of very-low-density lipoproteins (VLDLs) and chylomicrons, which play an important role in metabolism as energy source and also help in transporters of dietary fat. High levels of triglycerides in the bloodstream leads to atherosclerosis, which indicates the risk of heart disease, coronary heart disease (CAD) and hypolipoprotenimia.