Objectives: To determine lansoprazole (LPZ) in dog plasma. Methods: A single-step liquidliquid extraction with tert-butyl methyl ether was used for LPZ extraction from plasma samples obtained. LPZ was determined by using reversed phase-high performance liquid chromatography (HPLC). | Journal of military pharmaco-medicine no2-2018 DETERMINATION OF LANSOPRAZOLE IN DOG PLASMA USING REVERSED PHASE-HIGH PERFORMANCE LIQUID CHROMATOGRAPHY Luong Quang Anh*; Vu Ngoc Thang** Tran Nguyen Ha***; Nguyen Ngoc Chien*** SUMMARY Objectives: To determine lansoprazole (LPZ) in dog plasma. Methods: A single-step liquidliquid extraction with tert-butyl methyl ether was used for LPZ extraction from plasma samples obtained. LPZ was determined by using reversed phase-high performance liquid chromatography (HPLC). Results: LPZ and internal standard were separated by using an isocratic mobile phase on reversed phase waters symmetry C18 column with the ultraviolet detection at 285 nm. Linearity range was - µg/mL (r > of the regression line). The lower limitation of quantitation was 50 ng/mL. Mean percentage recoveries were from to . HPLC method was validated with intra-day and inter-day precision of - and - , respectively; accuracy was from to . LPZ was stable in plasma samples stored at four different degradation conditions. Conclusions: The method was successfully applied to determine LPZ in dog plasma samples. * Keywords: Lansoprazole; High performance liquid chromatography; Dog plasma; Validation. INTRODUCTION Lansoprazole, a proton pump inhibitor, reduces gastric acidity, an important factor in treating acid-related disorders such as gastric ulcers, duodenal ulcers, and reflux oesophagitis. LPZ is used to treat gastroesophageal reflux, ulcers, acid-related dyspepsia, etc [6]. LPZ is 97% bound to plasma proteins and shows its effectiveness correlating to drug concentration in object plasma. To estimate LPZ in plasma, some studies revealed that HPLC method was necessary [1, 2, 3, 5]. However, there have been studies for determination of LPZ in plasma in Vietnam up to now. Hence, we have studied to determine LPZ in dog plasma corresponding with drug quality control requirements in fluids. This research .
