Time dependent synthesis of gold nanoparticles using chitosan as reducing agent: A spectroscopic approach

The present study attempted synthesis of gold nanoparticle using chitosan from shrimp waste and evaluated the kinetics (AuNPs) formation. Two different forms (high molecular weight medium forms) were used for preparation AuNPs. formation nanoparticles was studied UV-VIS spectra obtained at time intervals during synthesis. typical spectrum non-aggregated spherical AuNPs 520 nm both maximum absorbance higher sample prepared with chitosan. results clearly indicated that characteristic surface plasmonic resonance (SPR) peak became recognisable 5 min heating high 3 This that, lower weight, faster nanoparticles. wavelength (λ) absorption maxima selected normalised respect to 15 min. sigmoidal shape kinetic curve implied autocatalytic character AuNP data samples fitted two step Finke-Watzky model constants derived. rate constant nucleation reaction found Keywords: AuNPs, Chitosan, Gold nanoparticles, Molecular Rate