A new HPLC method for the assay of Levofloxacin and its application in drug-metal interaction studies

A simple reversed phase HPLC method has been successfully developed and validated for the quantitative determination of levofloxacin (LVX) in bulk material, pharmaceutical formulation and serum. Purospher STAR C18 (25 cm x 4.6 mm, 5 µ m) was used. The mobile phase MeOH: H2O (70:30, v/v) was delivered at a flow rate of 1 Ml min-1 . The proposed method is specific, accurate with a recovery of 100  0.02. The detection limits were 2 ng with an RSD  0.1 (n=6).The anticipated method is applicable to routine analysis of LVX in pharmaceutical formulations and human serum samples. The method was applied to study the In vitro availability of levofloxacin in presence of various elements essential to the human body, like magnesium, calcium, chromium, copper Zinc and iron. The availability of Levofloxacin in presence of these elements was depressed up to 21% in simulated gastric juice, while up to 5% in pH 7.4 and 27% in simulated intestinal juice.