Increased usage of nanoparicles in biomedicine has inspired the making of this research. It's goal is to enrich the knowledge and improve the understanding of mechanisms during the shyntesis of nanoparticles. The potencial products of nanoparticles synthesis were chosen from a list of oxidation reactions of citric acid, compiled by studying the literature. The experiment consists of two parts. The first part is Turkevich's method of making nanoparticles in labaratory of Medical research institute in Zagreb, followed by NMR spectroscopy at Institute for organic chemistry on Faculty of Pharmacy and Biochemistry. The understanding of oxidation mechanisms of citric acid was expanded and the stability of nanoparticle water suspension was clarified by analizing the NMR spectrum of reaction mixtures. The most expressed signal in almost every spectrum corresponds to the chemical shift of acetone, which is created in catalytic dehydration of citric acid. Presence of acetone was experimentaly proven by adding the known substance in the sample, which amplified the existing signal. Except acetone, in lower magnetic field region, the expanding signal appeared which represents the citric acid in interaction with formed gold nanoparticles, that is „coating agent“ as described in the paper. Besides the expanding signal, there are some discreet signals which indicate that there are oxidation intermidiate products as described in introductory part and their chemical shifts correlate with predicted. The molecules in question are dicarboxyacetone and acetoacetate which are created by modulating the reaction conditions. All these evidance shows that there are impurities in shyntesis mixture of nanoparticles.