Validation of RP-HPLC method for quantification of ketoconazole in two-stage model of biorelevant dissolution: application to supersaturation study

Background Supersaturation may occur in weakly base drugs due to the physiological pH in the gastrointestinal (GI) tract cause their pH depends on solubility. The biorelevant medium used in this study were simulated gastric fluid (SGF) and Fasted State Simulated Intestinal Fluid (FaSSIF). Aims The in vitro evaluation of the supersaturation study measures the drug concentrations in solution as a function of time (concentration-time profiles). The method for analysis of concentration ketoconazole in supersaturation study has been validated. Settings and design A Two-Stage model of biorelevant dissolution is one of the methods to create the supersaturation condition. The method approach aims to simulate the condition of the drug in the gastrointestinal tract from gastric to intestine using a modification of the United States Pharmacopeia (USP) dissolution procedure and biorelevant medium. Material and methods The chromatographic system consisted of a reversed-phase C18 column (250×4.6 mm, 5 μm) at a flow rate of 1 ml/min, a detection wavelength of 232 nm, and a retention time of about 3 min for ketoconazole. Results The linearity of the calibration curves in the concentration range was good (R2 = 0.9995). The method was accurate with recoveries in the 100-103 range and precise ( relative standard deviation RSD of intraday variation was 0.85-1.57 and 0.3-1.61). The result of LOD was 0.230 μg/ml, and LoQ was 0.698 μg/ml. Conclusion The proposed method was selective, accurate, precise, and sensitive. So the method can be used to analyze the concentration of ketoconazole in supersaturation conditions induced by pH-shift in medium biorelevant. © 2022 Turkish Journal of Emergency Medicine.