DETERMINATION OF QUINOLONE ANTIBIOTICS IN GROWTH MEDIA BY REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A simple, accurate, precise, and versatile high-performance liquid chr omatographic (HPLC) method was developed and validated for the determi nation of three quinolone antibiotics in Mueller-Hinton broth. The flu oroquinolone agents studied were ciprofloxacin, ofloxacin, and sparflo xacin; other quinolone agents have been identified using this method b ut not validated in this matrix (levofloxacin, clinafloxacin, temaflox acin, and trovafloxacin). In addition, several other biological growth mediums have been investigated (human serum, human urine, Todd-Hewitt growth media, Ensure enteral feeding solution, and Haemophilus growth media). This method uses UV detection (280 nm), a simple, one-step pr otein precipitation extraction, and separation using a C-18 column wit h an isocratic, ion-pairing mobile phase. An appropriate internal stan dard was obtained by using another quinolone antibiotic of differing r etention time. The calibration curves were linear (r(2) greater than o r equal to 0.999) over a concentration range of 0.0625-20.0 mu g/ml wi th a lower limit of quantification of 0.1 mu g/ml. The intra-day and i nter-day coefficients of variation were less than 15%. (C) 1998 Elsevi er Science B.V.