Quantification of a novel natural antioxidant (UP302) in rat plasma using ultra-high performance liquid chromatography-tandem mass spectrometry

UP302 is a novel natural antioxidant isolated from Dianella ensifolia (Liliaceae). In the investigation, a specific and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry for quantitative determination of UP302 in rat plasma was developed and validated. UP302 and the internal standard daidzein were extracted from 1004 mu L aliquots of rat plasma using methanol. Detection of UP302 and IS was done by tandem mass spectrometry, operating in negative ion and selected reaction monitoring acquisition mode. The precursor-product ion transitions monitored for UP302 and daidzein were m/z 301.1 -> 135.2 and 252.9 -> 132.0, respectively. The linearity of the method was observed within the concentration range of 5-2000 ng/mL. Intra- and inter-day assay variations were less than 15%. and the accuracy values were between 99.2% and 107.3%. The method was successfully applied to stability investigation of UP302 incubated in rat plasma at 37 degrees C and measurement of UP302 in plasma after intravenous administration of UP302 to rats at a single dose of 5 mg/kg. Incubation stability revealed that within first one hour, UP302 was rapidly declined approximately 35% and remained stable after 4 h. Pharmacokinetic values of half-life, volume of distribution, systemic clearance and mean residence time were 0.87 +/- 0.58 h, 6.90 +/- 3.35 L/kg, 5.89 +/- 1.21 L/h kg and 0.34 +/- 0.13 h, respectively. (C) 2011 Elsevier B.V. All rights reserved.