ABSTRACT
In the present work, binary complexes of Copper(II), Cadmium(II) and Zinc(II) with metformin hydrochloridehave been studied potentiometrically. Stability constants of binary complex systems have been estimated by themethod proposed by Irving-Rossotti at 25ºC and 0.11M ionic strength (NaClO4) in aqueous solution. Theconditional formation constants of the complexes formed between ligand and metal were calculated according topH function. The maximum values of the conditional formation constants were found to be in accordance with themixed metal-ligand complex formation constants in a given pH region. In addition to these, the molar fractionswere calculated using the formation constants of the mixed metal-ligand complexes. As a result of theexperimental study, the values of stability constants of metal-ligand complexes at 25ºCare as noted below:logK1=8.45; logK2=8.30 for Zn(II)-Metformin hydrochloride; logK1=8.78 ; logK2=8.00 for Cu(II)-Metforminhydrochloride: logK1=8.18; logK2=7.36 for Cd(II) – Metformin hydrochloride.
ABSTRACT
In this study, simple, rapid and accurate UV-Vis spectrophotometric method was developed for the determination ofcomplexes stoichiometry of Cu(II)-bupropion hydrochloride, Ca(II)-bupropion hydrochloride, Cd(II)-bupropionhydrochloride, Mg(II)-bupropion hydrochloride and Zn(II)-bupropion hydrochloride. The spectrums of the complexesformed between bupropion hydrochloride with Cu (II), Ca (II), Cd (II), Mg (II) and Zn (II) metal cations were taken in therange of 500 to 190 nm and the stoichiometry of the complexes formed between bupropion hydrochloride with Cu (II), Ca(II), Cd (II), Mg (II) and Zn (II) metal cations were determined by using the mole ratio method at maximum wavelength(λmax=252 nm). The stoichiometry of Cu(II)-bupropion hydrochloride, Ca(II)-bupropion hydrochloride, Cd(II)-bupropionhydrochloride and Zn(II)-bupropion hydrochloride were calculated as 1:1, but Mg(II)-bupropion hydrochloride complexwas calculated as 1:2. The recovery was found 95.0% for bupropion hydrochloride. Lambert-Beer’s obeyed theconcentration range of 1.40-6.91 µg/mL for bupropion hydrochloride. The LOD and LOQ were found to be 13.81 and 1.38µg/mL for bupropion hydrochloride, respectively. The interaction between bupropion hydrochloride with Cu (II), Ca (II), Cd(II), Mg (II) and Zn (II) were investigated by applying UV-visible spectrophotometric method, and satisfactory results wereobtained