Determination of Oleuropein in Cosmetics by Ultra Performance Liquid Chromatography-Triple Quadrupole Tandem Mass Spectrometry

An ultrahigh performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-MS/MS)was established to quickly and accurately determine the content of oleuropein in cosmetics.The samples were extracted with methanol-aqueous solution,and the mobile phase with methanol-formic acid solution(0.1 mol/L)=40∶60 was separated by Agilent ZORBAX Eclipse Plus C18(2.1 mm×50 mm×1.8μm-Micron)column temperature 30℃,flow rate 0.3 mL/min.The MS end was detected by electrospray negative mode ionization(ESI-)and multiple reaction monitoring(MRM)mode.The results show a good linear relationship in the range of 0.002~5 mg/L,with a correlation coefficient R2 of 0.999,5.Method recovery range from 84.2%~107.6%and the relative standard deviation RSD is 5.8%.The detection time is 5 min,the detection limit is 0.000,6 mg/L,and the limit of quantification is 0.002 mg/L.This method has the advantages of convenient operation,low quantification limit,high precision and good repeatability,and is suitable for measuring the content of oleuropein in many kinds of cosmetics.

An Automatic Solid Phase Extraction and Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry for Determination of Seven Microcystins at Ultra-Trace Levels in Surface Water

A method was developed for the detection of seven microcystins(microcystin-LR, RR, YR, LA, LY, LW and LF) in surface water using automatic solid-phase extraction(A-SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS). The automated solid-phase extraction system was used to extract microcystins(MCs) from water samples. UPLC-MS/MS was used to determine MCs concentrations in just 5 min. Method detection limits were from 0.3 to 0.9 ng/L, microcystin recoveries ranged from 83.8% to 114%, and the relative standard deviation(RSD) varied from 5.6% to 12.5%. This analytical approach was found to be simple, highly sensitive, accurate, which required little manual operation. Additionally, to validate this analytical method, A-SPE+UPLC-MS/MS was applied to characterize the concentration of MCs in Taihu Lake, Wuxi, China.

Analysis and Identification of Chemical Constituents of Fenugreek by UPLC-IT-MSn and UPLC-Q-TOF-MS

Fenugreek, a traditional Chinese medical plant, has been widely used as food ingredients because of its out- standing medicinal qualities. The hypoglycemic activity of fenugreek is one of its important pharmacological properties. Both of saponin and flavonoid components have the hypoglycemic activity and their contents in fenugreek are 4%--8% and 1% ---2%, respectively. This paper focused on these two types of components to carry out purification research and chemical analysis. The heating reflux extraction method and macroporous resin purification method were designed to prepare the saponins and the flavonoids components from defatted fenugreek seeds. Petroleum ether ultrasonic skim and 70% ethanol refluxing were used for the extraction of saponins and flavonoid from fenugreek. The column of DM130 macroporous resin and D101 macroporous resin were respectively used to prepare fenugreek saponin and flavonoid components, and the total contents of them were 78.56% and 62.28%, respectively. The saponin and flavonoids were subsequently analyzed by an ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry（UPLC-Q-TOF-MS） along with an ultra-performance liquid chromatography and ion-trap tandem mass spectrometry（UPLC-IT-MS＂）. As a result, 57 saponins and 19 flavonoid compounds were characterized. The obtained results will provide a theory basis for further research on fenugreek, as well as research and development of hypogly- cemic new drugs.