Identification and Quantification of Leptin in Serum by using a Disposable electrochemical Immunosensor

Abstract

Obesity has already become one of the most common medical condition in the world. Leptin has been reported that it has essential role in obesity. The identification and quantification procedure of hormone leptin using disposable electrochemical immunosensor is described in this paper. Serum has been prepared from diet-induced obesity (DIO) model (C57BL/6J, male). DIO model is induced by high fat feed for over 2 months with above 30% of body weight. We used immune- assay method involving in the target analyte (leptin) and polyclonal anti-leptin antibody which has been immobilized on disposable electrodes by chemical linkers, 4-mercaptobenxoic acid (4-MBA), N-hydroxysuccinimide (NHS) and N-ethyl-N′-(3-dimethyl aminopropyl) carbo diimide (EDC). A linear calibration plot has also suggested with a specific concentration range between 100pg/mL and
100ug/mL by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The usefulness of the immune sensor was evaluated by comparing with enzyme-linked immunosorbent assay (ELISA). This attractive method with the simplicity and miniaturization of the required instrumentation would be promising alternative in the development of portable devices for clinical analysis.