Photochemical activity and fluorescence of electrophoretic fractions of aquatic humic matter

A combination of sephadex gel-chromatography and polyacrylamide gel electrophoresis was used to obtain stable electrophoretic fractions with different molecular sizes from a preparation of humic substances isolated from river water by reverse osmosis. The photochemical activity of humic substances and their fractions was determined. For the first time it is shown that low-molecular fractions of aquatic humic substances, when irradiated by polychromatic light, can intensely fluoresce and initiate the formation of singlet O₂, effectively destroying model compound furfural. The photochemical activity and intensity of fluorescence of high-molecular fractions is insignificant. The obtained data will help to extend the current knowledge in the field of natural water hydrochemistry about the ways of its natural self-purification from anthropogenic pollutants.