నైరూప్య

Comparative Study of Stability Constant of Antibacterial Drugs with Rare Earth Metal Ions

Shailendrasingh V. Thakur, Mazahar Farooqui, S. G. Shankarwar and S. D. Naikwade

In the present work, the stability constant of antibacterial drugs oxytetracycline hydrochloride (OTC), cefotaxime sodium (CFO) and ceftriaxone sodium (CFT) complexes with rare earth metal ions La (III), Ce (III), Nd (III), Sm (III), Gd (III), Tb (III) and Dy (III) have been investigated using pH metric titration technique in 20% (v/v) ethanol-water mixture at 25oC and at an ionic strength of 0.1 M NaClO4. The method of Calvin and Bjerrum as adopted by Irving and Rossotti has been employed to determine metal-ligand stability constant (log K) values. It is observed that rare earth metal (Lanthanide) ions forms 1 : 1 and 1 : 2 complexes.