Synthesis, characterisation and catalytic activity of gold and silver nanoparticles in the bio-sensor application

Most of the hydrogen peroxide (H2O2) bio-sensors developed till date are based on enzymes and proteins causing them to have a limited lifetime. Moreover, complex procedures are followed for sensor fabrication. Therefore, an inorganic material-based sensor, with a simple design and longer shelf life is highly desirable. In this work, surfactant-metal (gold and silver) nanoparticles are prepared in aqueous solutions containing cetyltrimethylammonium bromide. The particle sizes of the metal nanoparticles obtained are characterised by UV–Vis, HRTEM, X-ray diffraction and FTIR; the average sizes of gold and silver nanoparticles are 8 and 10 ± 0.2 nm, respectively. The nanoparticles are tested for H2O2 detection. The sensor is characterised and tested using samples from M to mM H2O2 range and a linear response is observed. Low-detection limits and high sensitivity are some of the advantages of this work. Same principle could be extended for the detection of other substrates as well.