Аннотация:Spectral properties of water-dispersible sorbent produced from humic acids (HA) extracted from brown coal and magneto-active nanoparticles were measured for the samples of different magnetite/HA ratio and the way of their preparation. The influence of iron (III) ions on spectral properties of HA in aqueous solution was investigated using Stern-Volmer plots describing HA fluorescence quenching. The Stern-Volmer dependences were found to be linear at concentration of iron (III) ions smaller 20 μmol/L and nonlinear at higher concentrations.