Complex formation of uranium(VI) with the amino acids L-glycine and L-cysteine: A fluorescence emission and UV-vis absorption study

The complexation of uranium(VI) with the amino acid L-glycine and L-cysteine has been investigated by time-resolved laser-induced fluorescence spectroscopy (TRLFS) and UV-vis spectroscopy at low pH range. The identified 1:1 and 1:2 uranyl-L-glycine complexes fluoresce and have similar absorbance properties. In contrast to the glycine system, uranyl forms with L-cysteine two different non-fluorescent 1:1 complexes showing individual absorbance properties under the given experimental conditions.The corresponding complex formation constants were calculated using the spectroscopic data.