Silver nanoparticles embedded three dimensional silicate sol-gel matrix modified electrode for nitrite sensor application

A simple amperometric sensor was fabricated by using silver nanoparticles (Agnps) embedded three dimensional silicate sol–gel (SG) matrix (SG–Agnps). The silver nanoparticles stabilised by SH functionalised 3–D silicate sol–gel network was coated on the glassy carbon electrode and used for the determination of nitrite ion in 0.1 M PBS (pH 7.2). The prepared silver nanoparticles–silicate sol–gel (SG–Agnps) modified electrode was characterised by UV–visible absorption spectroscopy, scanning electron microscopy (SEM) and electrochemical method. The electrochemical behaviour of SG–Agnps modified electrode was studied by using potassium ferricyanide as a redox marker to probe the tunable kinetic barrier of the dispersed silver nanoparticles in silicate sol–gel matrix. The SG–Agnps film was used as nanomaterials comprised electrochemical device for direct electrocatalysis and amperometric sensing of nitrite ion. The silver nanoparticles embedded silicate sol–gel film showed good stability and sensitivity with an experimental amperometric detection limit of 4 M. The fabrication of SG–Agnps modified electrode was very simple and it showed fast amperometric response and reproducible results for nitrite sensing.