Dissociation Constants of Ethane-1-hydroxy-1,1-diphosphonate [EHDP] and Dichloromethylene-diphosphonate [Cl2MDP] for H+, Ca2+, Mg2+ and Zn2+

Abstract

Abstract Diphosphonates, Dissociation Constants The dissociation constants of ethane-l-hydroxy-1,1-disphosphonate [EHDP] and dichloro-methylene-diphosphonate [Cl2MDP] for H+, Ca2+, Mg2+ and Zn2+ have been determined from pH-titration curves. EHDP forms more stable chelates with Ca2+, Mg2+ and Zn2+ than Cl2MDP. Cl2MDP is a stronger acid than EHDP.