Abstract
Lipase has been immobilized onto sol-gel derived nanostuctured cerium oxide (Nano-CeO2, 35 nm) film deposited onto indium-tin-oxide ([TO) coated glass plate for tributyrin detection. The Nano-CeO2/ITO electrode and lipase/nano-CeO2/ITO bioelectrode have been characterized using scanning electron microscopy (SEM) and cyclic voltammetry (CV). The electrochemical response of lipase/nano-CeO2/ITO bioelectrode towards tributyrin, investigated using CV studies, exhibits linearity, detection limit and shelf life as 50-500 mg/dL, 32.8 mg/dL and 12 weeks, respectively. The value of the apparent Michaelis-Menten constant (K-m(app)) obtained as 22.27 mg/dL (0.736 mM) for lipase/nano-CeO2/ITO bioelectrode indicates high affinity of lipase with tributyrin. Attempts have been made to detect triglyceride concentration in serum samples. (C) 2009 Elsevier B.V. All rights reserved.