Spectrophotometric study of stability constants of cimetidine-Ni(II) complex at different temperatures

Cimetidine, a histamine H-2-receptor, has a structure which enables it to act as a chelating agent. The formation of nickel(II) complex with cimetidine has been studied spectrophotometrically at an absorption maximum of 622 nm at different temperatures. The data show that nickel(II) and cimetidine combine in the molar ratio of 1:2. The stability constants of the complex were calculated to be 1.40-2.4 x 10(8) by continuous variation method and 1.24-2.4 x 10(8) by mole ratio method at 25 and 40 degrees C, respectively. The immediately formed complex shows stability with respect to time and temperature. (C) 2010 King Saud University. Production and hosting by Elsevier B. V. All rights reserved.