DIRECT AND DERIVATIVE SPECTROPHOTOMETRIC ESTIMATION OF GEMIFLOXACIN BY CHELATION WITH PALLADIUM(II) ION

Authors: D.Madhuri*1, K.B.Chandrasekhar1,N.Devanna1,G.Somasekhar2

1Department of Chemistry, J.N.T.University, Anantapur, A.P. ,INDIA; 2Department of Pharmacy, Omer-Al-Mukhtar University, LIBYA; *Email:madhuri.pharma@redifmail.com

A simple ,sensitive and accurate spectrophotometric method was described for the determination of Gemifloxacin mesylate (GFX) a broad spectrum flouroquinolone anti bacterial  either  in pure form or in the tablet .The method is based on chelate formation between GFX and Palladium (Pd II) in aqueous media. The complex showed an absorption maximum at 430nm,Ist derivative at 480nm and Second derivative at 500nm respectively with apparent molar absorpitivities of 1.365x10 ⁴  L-M^-1Cm^-1,^, 9.37x10⁴ L-M^-1Cm^-1 for Ist order derivative, 1.59X10LM^-1Cm^-1 for 2^nd order derivative  respectively. The solution of the complex obeyed beer’s law in the concentration range of 2to 14 µg/ml  for zero order,1 to 10 µg/ml   for Ist order and 1to 15  µg/ml   for 2^nd order respectively. The limit of detection and Limit of quantification were calculated and RSD were less than 0.153.The chelate composition between GFX and Pd(II) ion was found to be 1:1 ratio determined by Job’s continuous method and by Molar ratio method. The proposed method was applied for the determination of GFX in tablets without interference from common excipients .The results obtained by the application of this procedure showed percentage recoveries were 99.8±0.153 for zero order , 100.02±0.177 for Ist order and 100.045±0.139 for 2^nd order respectively.

Keywords : Gemifloxacin mesylate, Chelate, Spectrophotometric , Pharmaceutical formulation.