Carboxyl Terminated Reduced Graphene Oxide (Crbxl-RGO) and Pt Nanoparticles Based Ultra-Sensitive and Selective Electrochemical Biosensor for Glutamate Detection

Here, an ultrasensitive enzymatic electrochemical L-glutamate sensor was successfully developed and characterized using carboxyl terminated reduce graphene oxide (Crbxl-RGO) and Pt nanoparticles as a supporting and catalyzing medium. Crbxl-RGO was drop casted on the Au substrate and Pt nanoparticles were electrodeposited on Crbxl-RGO/Au modified substrate. L-Glutamate dehydrogenase-chitosan (GLDH-chit) composite was immobilized on the sensing area using EDC/NHS bonding material treatment. The physical characteristic of the sensor matrix was monitored through field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS), Energy dispersive spectroscopy (EDX) and analytical characterization was analyzed by using cyclic voltammetry (CV), electrochemical impedance spectroscopy and differential pulse voltammetry (DPV). Under optimized condition the sensor showed sensitivity of 973 ± 4 μA/mMcm 2 , wide linear range 0.004–0.9 mM and limit of detection 0.1 μM that indicates promising approach for detecting L-glutamate.