RAOUL VASILE LUPUSORU, LAURENTIU SIMION, ION SANDU, DANIELA ANGELICA PRICOP, AURICA CHIRIAC, VLADIMIR POROCH AGING STUDY OF GOLD NANOPARTICLES FUNCTIONALIZED WITH CHITOSAN IN AQUEOUS SOLUTIONS We studied the way in which stability and physicochemical properties of gold (Au) nanoparticles (NP) coated with chitosan are influenced by the molecular weight of chitosan and Au precursor concentration when samples are subjected to aging. Pharmaceutical use of AuNPs coated with chitosan is closely related to stability and physicochemical properties in relation to storage conditions and processing. For this purpose, series of AuNPs of different sizes were prepared by aqueous chemical reduction method using chitosan with various molecular weights as template. The physicochemical properties and stability at room temperature of AuNPs in aqueous solutions of chitosan have been investigated by following the temporal evolution of surface plasmon absorbance, Zeta potential, average dimension, and Au-chitosan interaction, after synthesis and through a period of 24 months. In our experiment, during the observed aging period, the AuNPs coated with chitosan presented a better colloidal stability, while using chitosan with medium molecular weight and medium concentration of Au precursor.
Keywords: chitosan-gold nanoparticles, aqueous chemical reduction method, template, stability, aging