COLORIMETRIC DETERMINATION OF SOME FLUOROQUINOLONE DERIVATIVES

Two sensitive procedures were described for the determination of two fluoroquinolone containing compounds namely; norfloxacin and ofloxacin. In these procedures methyl orange and bromophenol blue were utilized in the determination of the concemed compounds by forming ion pair complex in buffered aqueous solution. The chloroform extract of the drug complexes were measured at ʎ max 422 and 414 nm with methyl orange and bromophenol blue, respectively. In procedure I, methyl orange was used at pH 3.5 for norfloxacin and pH 4 for ofloxacin. The proposed method was applied for determination of Noroxin and Tarivid tablets. In procedure II, bromophenol blue was used at pH 2.9 for ofloxacin and the procedure, then applied for determination of Tarivid tablets with mean percentage recovery 99.84 ± 1.76. The results were compared with the official method and showed no significant difference.