Abstract:

A resonance light scattering detection method of ascorbic acid is reported based on the formation of silver nanoparticles(NPs). Ascorbic scid(vitamin C,VC)) could reduce Ag(NH3)+2 to form the silver nanoparticles, resulting in strong plasmon resonance light scattering(PRLS) signals characterized at 544 nm, which could be measured using a common spectrofluorometer. It is found that the PRLS intensities were proportional to the ascorbic acid concentrations in the range of 0.2~7.0 μmol/L with R2=0.9988 and detection limit(3σ/k) of 8.1×10-9 mol/L. The presence of a physically adsorbed layer of the product of the redox reaction on the surface of colloidal silver could prevent irreversible aggregation of silver NPs. The conditions of the reaction and the interference of the common ions are investigated. For the determination of ascorbic acid in VC tablets and beverage samples, the recovery was within the range of 94.5%~97.0%. Results suggested that the method possessed easy of implementation, high sensitivity, and better recovery, and so on.

Key words: Detection, Silver nanoparticles, Resonance light scattering, Ascorbic acid