DETERMINATION OF A POORLY SOLUBLE DRUG, IBUPROFEN IN RAT PLASMA BY A SIMPLE HPLC ANALYSIS AND ITS APPLICATION IN PHARMACOKINETIC STUDY

In this study, a reversed-phase high performance liquid chromatography (RP-HPLC) method has been developed for the quantification of ibuprofen in rat plasma. The mobile phase consisted of a mixture of acetonitrile and water that was adjusted to pH 2.5 using orthophosphoric acid (70:30). The flow rate was set at 0.5 ml/min and effluent was monitored by using UV detector at a wavelength of 223 nm with retention time of 6.1 min. The chromatographic separation was carried out using a C18 (150 mm × 4.6 mm i.d.) column. The proposed method was validated based on linearity, accuracy and precision. The linearity of ibuprofen was in the range of 0.39-50 µg/ml with mean correlation coefficient of 0.999. The percentage mean recovery was found to be at 99.16%, while the coefficients of variation of within-day and between-day measurements were all found to be less than 5%. The limit of quantification (LOQ) and limit of detection (LOD) of the method were 0.296µg/ml and 0.098µg/ml, respectively. The method was further engaged to identify the pharmacokinetic profiles of ibuprofen nanoemulsion and ibuprofen oil solution after oral administration with AUC value of 6670.10 ± 283.83µg/ml∙hr and 3060.32 ± 169.93µg/ml∙hr, respectively.