ABSTRACT
Styraxlignolide A is a pharmacologically active ingredient isolated from Styrax japonica Sieb. et Zucc. A rapid, selective, and sensitive liquid chromatographic method with electrospray ionization tandem mass spectrometry was developed for use in the quantification of styraxlignolide A in rat plasma. Styraxlignolide A was extracted from rat plasma using ethyl acetate at neutral pH. The analytes were separated on an Atlantis dC18 column using a mixture of methanol and ammonium formate (10 mM, pH 3.0) (70:30, v/v) and detected by tandem mass spectrometry in multiple reaction monitoring mode. The standard curve was linear (r(2) =0.9978) over the concentration range of 100-10000 ng/mL. The lower limit of quantification was 100 ng/mL using 50 µL of plasma sample. The coefficient of variation and relative error for intra- and inter-assays at four QC levels were 1.6-8.3% and from -12.0 to -1.7%, respectively. The present method was applied successfully to the pharmacokinetic study of styraxlignolide A after intravenous administration of styraxlignolide A at a dose of 10 mg/kg in male Sprague-Dawley rats.
Subject(s)
Disaccharides/blood , Lignans/blood , Styracaceae/chemistry , Animals , Chromatography, Liquid , Disaccharides/administration & dosage , Disaccharides/chemistry , Lignans/administration & dosage , Lignans/chemistry , Male , Molecular Structure , Rats , Rats, Sprague-Dawley , Spectrometry, Mass, Electrospray Ionization , Tandem Mass SpectrometryABSTRACT
Sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) using a hydrophilic replaceable polymer network matrix was applied to characterize the polyethylene glycol(PEG)ylated interferon alpha (PEG-IFN). The SDS-CGE method resulted in a clearer resolution in both the PEG-IFN species and the native IFN species. The distribution profile of PEGylation determined by SDS-CGE was consistent with that obtained by SDS-polyacrylamide gel electrophoresis (PAGE) with Coomassie blue or barium iodide staining. The result was also compared using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. SDS-CGE was also useful for monitoring the PEGylation reaction to optimize the reaction conditions, such as reaction molar ratio. This study shows the potential of SDS-CGE as a new method for characterizing the PEGylated proteins with advantages of speed, minimal sample consumption and high resolution.