Gold nanoparticles incorporated 3-(trimethoxysilyl)propyl methacrylate modified electrode for non-enzymatic electro-sensing of urea.

Abstract

We describe non-enzymatic electrochemical sensor for urea based on the electrocatalytic activity of gold nanoparticle (AuNPs) incorporated in 3-(Trimethoxysilyl)propyl methacrylate (TMSPMA) network. AuNPs incorporated in TMSPMA network on poly crystalline gold electrode show excellent electrocatalytic activity towards urea sensing. Uniform distribution and interaction of Au nanoparticles in nanospace of TMSPMA network are probably the key factors for catalytic effect of the nanocomposite. Nanocomposite is characterized by UV-visible diffuse reflectance spectroscopy, cyclic voltammetry, field emission scanning electron microscopy and X-ray photoelectron spectroscopy before using as urea sensor. The sensing platform is found to be highly sensitive and shows linear response in wide range for urea concentration with a sensitivity of 1.13 microA/microM and limit of detection as 2.08 microM respectively at S/N (signal-to-noise ratio): 3. It is also observed that the sensor does not suffer interference from phosphate and sulphate ions. Further, a possible mechanism for electro-sensing of urea with modified electrode has also been proposed.