An ultra-performance liquid chromatography quadrupole time of flight mass spectrometry （UPLC-qTOF-MS/MS） method was developed and validated for the simultaneous determination of glycyrrhizin and glycyrrhetic acid. T...An ultra-performance liquid chromatography quadrupole time of flight mass spectrometry （UPLC-qTOF-MS/MS） method was developed and validated for the simultaneous determination of glycyrrhizin and glycyrrhetic acid. These analytes were separated on a reverse phase C18 column using a mobile phase of acetonitrile：2% acetic acid in water （75：25, v/v） with a flow rate of 200 μL/min. The qTOF-MS was operated under multiple reaction monitoring （MRM） mode using the electrospray ionization （ESI） technique with positive ion polarity. A comparison of three different extraction techniques i.e. accelerated solvent extraction （ASE）, extraction under ultrasonic waves （USW） and the classical extraction by percolation （CE） method was done and quantification of these extracts was also carried out by the proposed method.展开更多
We described the first results of a quantitative ultra performance liquid chromatographytandem mass spectrometry method for a novel antimicrobial peptide （phylloseptin, PSN-1）. Chromatographic separation was accompl...We described the first results of a quantitative ultra performance liquid chromatographytandem mass spectrometry method for a novel antimicrobial peptide （phylloseptin, PSN-1）. Chromatographic separation was accomplished on a Waters bridged ethyl hybrid （BEH） C18 （50mm× 2.1 mm, 1.7 μm） column with acetonitrile-water （25：75, v/v） as isocratic mobile phase. Mass spectrometry detection was performed in the positive electrospray ionization mode and by monitoring of the transitions at m/z 679.6/120, 509.6/120 （PSN-1） and m/z 340.7/165 （Thymopentin, IS）. Protein precipitation was investigated and the recovery was satisfactory （above 82%）. The method was shown to be reproducible and reliable with intra-day precision below 5.3%, inter-day precision below 14.2%, and linear range from 0.02 to 2 lag/mL with r〉0.994. The method was successfully applied to a pharmacokinetic study of PSN-1 in rats after intravenous administration.展开更多
文摘An ultra-performance liquid chromatography quadrupole time of flight mass spectrometry （UPLC-qTOF-MS/MS） method was developed and validated for the simultaneous determination of glycyrrhizin and glycyrrhetic acid. These analytes were separated on a reverse phase C18 column using a mobile phase of acetonitrile：2% acetic acid in water （75：25, v/v） with a flow rate of 200 μL/min. The qTOF-MS was operated under multiple reaction monitoring （MRM） mode using the electrospray ionization （ESI） technique with positive ion polarity. A comparison of three different extraction techniques i.e. accelerated solvent extraction （ASE）, extraction under ultrasonic waves （USW） and the classical extraction by percolation （CE） method was done and quantification of these extracts was also carried out by the proposed method.
文摘We described the first results of a quantitative ultra performance liquid chromatographytandem mass spectrometry method for a novel antimicrobial peptide （phylloseptin, PSN-1）. Chromatographic separation was accomplished on a Waters bridged ethyl hybrid （BEH） C18 （50mm× 2.1 mm, 1.7 μm） column with acetonitrile-water （25：75, v/v） as isocratic mobile phase. Mass spectrometry detection was performed in the positive electrospray ionization mode and by monitoring of the transitions at m/z 679.6/120, 509.6/120 （PSN-1） and m/z 340.7/165 （Thymopentin, IS）. Protein precipitation was investigated and the recovery was satisfactory （above 82%）. The method was shown to be reproducible and reliable with intra-day precision below 5.3%, inter-day precision below 14.2%, and linear range from 0.02 to 2 lag/mL with r〉0.994. The method was successfully applied to a pharmacokinetic study of PSN-1 in rats after intravenous administration.
