Abstrakt

Two spectrophotometric methods for estimation of clarithromycin in pharmaceutical formulations and human plasma based on charge transfer complexes

Mohamed E.El-Zaria

Two novel, simple, and sensitive spectrophotometric methods were applied successfully to the determination of clarithromycin (CLM) in pure, pharmaceutical dosage form, and humane plasma with good accuracy and precision. The methods were based on chrage transfer complexes (CTCs) with both iodine (I2) as -acceptor and tetracyanoethylene (TCNE) as - acceptor. The complexes were stable at least for two days after its formations. The orange and yellow CTC species have an absorption maxima at 363 and 420nm for I2 and TCNE, respectively, with a molar absorptivity between 2985 to 3497 and 6877 to 9872 lmol-1 cm-1. The stoichiometries of the CTCswere defined by JobÂ’s, molar ratio and striaght line methods and were found to form 1:1 stable stoichiometric complexes.Also, the formation constants and thermodynamic parameters(ÄHo, ÄSo, and ÄGo) of the resulting CTCs were determined. The optimum reaction conditions and other analytical parameters were also investigated. The developed methods were found to be linear over concentration ranges of 35-135 and 15- 95gml-1 with limit of detection 0.12 and 0.18gml-1 for iodine and TCNE methods, respectively. The methods were shown to be applicable to the determination of CLMin human plasma.