Determination of levofloxacin by HPLC with fluorescence detection in human breast milk.

A new HPLC method with fluorescence detection has been developed and validated for the determination of levofloxacin, one of the fluoroquinolone class antibiotics, in breast milk. Chromatographic separation was carried out on a reversed phase C18 column with acetonitrile and 10 mM -phosphoric acid (25:75, v/v) mobile phase composition. Moxifloxacin was used as internal standard and the peaks were detected by fluorescence detection. Calibration graph was found linearly within the range of 2.5-500 ng/ml. Limit of detection and limit of quantification were found to be 0.63 and 2.11 ng/ml, respectively. Mean absolute recovery was 96.18%. The developed method has been successfully applied to the determination of levofloxacin in human breast milk taken from two healthy volunteers.