Complexation Behavior of Guanine with Th4+, UO22+, and Ce3+ at Various Temperatures

The complexation of guanine with Th4+, UO22+, and Ce3+ was investigated using the potentiometric method at a constant ionic strength of I = 0.10 mol.dm(-3) (KCl) in aqueous solutions at elevated temperatures. For each metal ion, stability constants were obtained from the pH-metric data using the program HYPERQUAD2006. The formation of monomeric and polymeric species was taken into consideration for each ion at (25, 37, and 45) degrees C. The thermodynamic parameters for the formation of the guanine complexes were calculated. In conclusion, it is indicated that the values of the stability constants change at various temperatures.