A simple chromatographic method for determining norfloxacin and enoxacin in pharmacokinetic study assessing CYP1A2 inhibition (original) (raw)
Related papers
Revista Brasileira De Ciencias Farmaceuticas, 2007
The development and validation of a simple and accurate method based on HPLC with ultraviolet detection for the quantification of norfloxacin (NFX) in human plasma and its application to a bioequivalence study between two norfloxacin formulations is described. NFX and the internal standard (cyprofloxacin) were extracted from plasma using liquid-liquid extraction. Chromatographic separation of norfloxacin, cyprofloxacin and plasma interferents was achieved with a C-18 column and a mobile phase consisting of 20 mM sodium hydrogen phosphate buffer pH 3.0 and acetonitrile (88:12, v/v) and quantitation was done at 280 nm. The method was linear from 25 to 3000 ng mL -1 (r 2 ≥ 0.997578), and norfloxacin and cyprofloxacin had an average recovery from plasma of 93.9% and 91.2% respectively. The RSD of inter-day quality control samples at the lower limit of quantification was less than 15%. After a single oral dose (400 mg) of norfloxacin administered to healthy human volunteers using a randomized 2x2 crossover design, pharmacokinetic parameters (AUC 0-t , AUC 0-∞ , C max , t 1/2 ) were derived from the plasma concentration curves for both formulations. Pharmacokinetic analysis of the data showed that the two formulations were bioequivalent, while no adverse reactions to the drug were observed.
Revista Brasileira de …, 2007
The development and validation of a simple and accurate method based on HPLC with ultraviolet detection for the quantification of norfloxacin (NFX) in human plasma and its application to a bioequivalence study between two norfloxacin formulations is described. NFX and the internal standard (cyprofloxacin) were extracted from plasma using liquid-liquid extraction. Chromatographic separation of norfloxacin, cyprofloxacin and plasma interferents was achieved with a C-18 column and a mobile phase consisting of 20 mM sodium hydrogen phosphate buffer pH 3.0 and acetonitrile (88:12, v/v) and quantitation was done at 280 nm. The method was linear from 25 to 3000 ng mL-1 (r 2 ≥ 0.997578), and norfloxacin and cyprofloxacin had an average recovery from plasma of 93.9% and 91.2% respectively. The RSD of inter-day quality control samples at the lower limit of quantification was less than 15%. After a single oral dose (400 mg) of norfloxacin administered to healthy human volunteers using a randomized 2x2 crossover design, pharmacokinetic parameters (AUC 0-t , AUC 0-∞ , C max , t 1/2) were derived from the plasma concentration curves for both formulations. Pharmacokinetic analysis of the data showed that the two formulations were bioequivalent, while no adverse reactions to the drug were observed. Recebido para publicação em 19 de dezembro de 2006. Aceito para publicação em 31 de maio de 2007.
Biopharmaceutics & Drug Disposition, 2000
The two formulations were: Uroxin ® (Julphar, United Arab Emirates) as test and Noroxin ® (Merck Sharpe & Dohme, BV, Netherlands). Both test and reference formulations were administered to each subject after an overnight fasting on 2 treatment days separated by 1 week wash-out period. After dosing, serial blood samples were collected for a period of 24 h. Plasma harvested from blood, was analysed for norfloxacin by a sensitive, reproducible and accurate HPLC method. Various pharmacokinetic parameters including AUC 0-t , AUC 0-, C max , T max , T 1/2 , and K el were determined from plasma concentrations for both the formulations and found to be in good agreement with reported values. AUC 0-t , AUC 0-, and C max were tested for bioequivalence after log-transformation of data. No significant difference was found based on ANOVA; 90% confidence interval for test/reference ratio of these parameters were found within a bioequivalence acceptance range of 80-125%. Based on these statistical inferences, it was concluded that Uroxin ® is bioequivalent to Noroxin ® .
Bioequivalence evaluation of norfloxacin tablets based on in vitro - in vivo correlation
Pakistan journal of pharmaceutical sciences, 2011
Present study was designed to establish in-vitro and in-vivo correlation (IVIVC) of two immediate release tablet formulations of 400mg Norfloxacin [Drug A as test and Drug B as reference]. Dissolution study was conducted in 0.1 N HCl using USP apparatus II. In-vivo evaluation was carried out in 18 healthy humans according to a single dose, two-sequence, and cross-over randomized with a wash-out period of one week. After dosing, serial blood samples were collected for a period of 10 hours. Plasma harvested from blood, was analyzed for norfloxacin by a sensitive, reproducible and accurate HPLC method. Various pharmacokinetic parameters were determined from plasma concentrations for both the formulations. Non-significant difference was found for test/reference ratio of these parameters and the value of F was found to be 0.99 which is in good agreement with the limits given in FDA and WHO guidelines for such parameters. Difference factor (f(1)), similarity factor (f(2)) and level A IVIV...
A rapid, simple, precise, specific, highly sensitive, accurate and reproducible isocratic reversed phase HPLC method was developed for the separation of five fluoroquinolones and validated for determination of norfloxacin for routine pharmaceutical quality control analysis in bulk and formulations. One of the salient aims for the method development is to accomplish constant, reproducible separation. The selection of good method is essential if this goal is to be achieved. RP-HPLC method was developed by using WELCHROM C 18 Column (4.6 X 250mm, 5µm), SHIMADZU LC-20AT prominence liquid chromatograph. The mobile phase consisting of phosphate buffer (pH-6.8)and acetonitrile in the proportion of 50:50 v/v under isocratic elution at a flow rate of 1mL/min was employed. The responses were measured at 281nm using SHIMADZU SPD-20A prominence UV-Vis detector. The retention time of norfloxacin, moxifloxacin, enrofloxacin, sparfloxacin and prulifloxacin were found to be 2.940 min, 3.363 min, 3.790 min, 4.013 min and 7.520 min, respectively. Chromatographic runtime was 10 min with elution window of 6 min and with a resolution of greater than 2.0 for all compounds. The developed method was validated according to ICH guidelines.The average recoveries ranged from 99.03 -100.36 %, with %RSD less than 2%. The concentration of calibration solutions was in the range of 2-10 μg/mL and LOD and LOQ were 0.1491 and 0.4519 μg/mL respectively. The method was successfully applied to analysis of norfloxacin in pharmaceutical formulation. It can also be extended for the determination of other four fluoroquinolones or their combinations.