DEPROTONATION ENERGETICS OF ADENINE, ADENOSINE, 5'-ADENOSINE MONOPHOSPHATE AND ADENOSINE-TRIPHOSPHATE IN WATER FROM EMF AND SPECTROPHOTOMETRIC MEASUREMENTS

The deprotonation constants of adenine (ADE) [K-1 and K-2], adenosine (ADO) [K-1 and K-2]. 5'-adenosine monophosphate (5'-AMP) [K-1, K-2 and K-3] and adenosine triphosphate (ATP) [K-3 and K-4] have been obtaine d for aqueous soutions from emf measurements on cells such as Pt, H-2 (g, 1 atm)/HA(m(1)), NaA(m(2)), KI(m(3))/Agl-Ag (where HA is the corre sponding acid of ADE, ADO, S'-AMP and ATP) at different temperatures. The pK values were fitted by the temperature equation : pK = AT(-1) B + CT by the least squares method and the related thermodynamic quant ities viz. Delta G degrees, T Delta S degrees and Delta H degrees were calculated from the coefficients A, B and C.