Spectrophotometric complexation of cephalosporins with palladium (II) chloride in aqueous and non-aqueous solvents

The complexation reaction of cephalosporins namely cefotaxime (CTX), cefuroxime (CRX), and cefazolin (CEFAZ) with palladium (II) ions have been studied in water and DMF in 25 °C by the spectrophotometric methods. The method is based on the formation of yellow to yellowish brown complex between palladium (II) chloride and the investigated cephalosporins in the presence of sodium lauryl sulfate (SLS) as surfactant. The complexation process was optimized in terms of pH, temperature and contact time. The stoichiometry of all the complexes was found to be 2:1 (metal ion/ligand) for CTX, CRX, and 1:2 for CEFAZ. The stoichiometry of palladium (II)–cephalosporins was estimated by mole ratio and continuous variation methods and emphasized by the KINFIT program. These drugs could be determined by measuring the absorbance of each complex at its specific λmax. The results obtained are in good agreement with those obtained using the official methods. The proposed method was successfully applied for the determination of these compounds in their dosage forms.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The chelate complex formed under the above mentioned conditions and measured spectrophotometrically can offer a sensitive, simple cheap and rapid procedure for the determination of the three cephalosporins in bulk, tablets and vials dosage forms. ► Also the complex formed was found to be soluble in presence of a surfactant, without the need for organic solvent to extract the reaction products. ► From the calculation of stability constant of the complex, the latter was found to be stable. ► The method had been validated for the determination of these antibacterials. ► The statistical analysis of the results confirmed that the developed method was accurate and precise and could be recommended for use in quality control labs.