Quantification of Au nanoparticles in cell cultures can be used for the estimation of potential risks arising from their applications. A novel method has been proposed for the electrochemical determination of nanoparticles adsorbed by living cells on the basis of stripping voltammetry on electrodes made of graphite materials. The detection limits are 2.6 and 0.4 mg/dm 3 for gold(III) and silver(I), respectively. The correlation between the number of nanoparticles absorbed by cells, the time of incubation of cells with nanoparticles and the nature of cells and nanoparticles has been determined. The influence of nanoparticles on the vitality of cell cultures has been estimated.