Simultaneous Determination of Some 5-Nitroimidazole Derivatives and Ciprofloxacin by High Performance Liquid Chromatography

Abstract:

Objective: An isocratic high performance liquid chromatographic method for simultaneous determination of Metronidazole, Tinidazole and Ciprofloxacin was developed. Method: Separation was achieved with a C₁₈ (250x4.6 mm, 5 μm) column. Optimal chromatographic conditions were: mobile phase consisting of acetonitrile: 0.3% o-phosphoric acid modified with 0.1% triethylamine (20:80 v/v) at a flow rate of 0.7 mL min-1, at 30°C and wavelength of 300 nm. Results: The retention times were 4.92 min for Metronidazole, 8.78 min for Tinidazole and 9.76 min for Ciprofloxacin. The responses were linear (R² = 0.9999) in the range of 12.5 – 100 μg mL-¹. The limits of detection were 0.012 µg mL-¹ for Metronidazole and Tinidazole and 0.04 µg mL-¹ for Ciprofloxacin. The limits of quantification were 0.125 µg mL-¹ for Metronidazole and Tinidazole and 0.4 µg mL-¹ for Ciprofloxacin. The recovery (%) was within the range of 99.57 – 100.3% for all analytes. Conclusion: The method developed can successfully be used for routine analysis and quality control of Metronidazole, Tinidazole and Ciprofloxacin.

Key words: Metronidazole, Tinidazole, Ciprofloxacin, RP-HPLC, Validation, Quality control.