Novel SPR based fiber optic sensor for vitamin A using Au@Ag core-shell nanoparticles doped SiO2-TiO2-ZrO2 ternary matrix

A novel SPR based vitamin A sensor using Au@Ag core-shell nanoparticles embedded SiO₂-TiO₂-ZrO₂ ternary matrix is reported for the first time. The prepared Au@Ag core-shell nanoparticles were found to have an average size of 30 nm using TEM analysis and the presence of Au and Ag were confirmed using EDS and AAS analysis. The sensing capability and selectivity of the produced Au@Ag core-shell nanoparticles were studied using absorption spectroscopy and was found to have good selectivity over other biomolecules. The practical application of such a sensor was elucidated by coating the title specimen on an optical fiber and its specificity towards vitamin A sensing was analyzed using transmittance spectra. The as prepared novel vitamin A sensor was found to have a linear response towards vitamin A concentration ranging from 10 to 1000 μM. An economical, low toxic and sensitive biosensor for vitamin A detection based on SPR mechanism is proposed in the current work.