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Simultaneous determination of adenine, uridine and adenosine in cordyceps sinensis and its substitutes by LC/ESI-MS 总被引:1,自引:0,他引:1
A simple, sensitive and reproducible high performance liquid chromatography-mass spectrometry coupled with electrospray ionization method for simultaneous separation and determination of adenine, adenosine and uridine was developed. The analytical column is a 2.0 mm× 150 mm Shimadzu VP-ODS column and volume fraction of the mobile phase is 86.5 %water, 12.0%methanol and 1.5%formic acid. 2-chloroadenosine was used as internal standard. Selective ion monitoring mode and selective ion monitoring ions at ratio of mass to electric charge of 136 for adenine, 268 for adenosine and 267 for uridine were chosen for quantitative analysis of the three active components. The results show that the regression equations and linear range are Y=0. 062X 0. 005 and 2.0 - 140.0μg · mL 1for adenine, Y=0. 049X 0. 004 and 4. 0 - 115.0 μg · mL-1 for uridine, Y=0. 154X 0. 014 and 1.0 - 125.0 μg · mL 1 for adenosine. The limits of detection are 0.6 μg · mL 1 for adenine, 1.0μg · mL-1 for uri dine and 0.2 μg · mL 1 for adenosine.The recoveries of the three constituents are from 96.6% to 103.2%. 相似文献
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1INTRODUCTION TraditionalChinesemedicines(TCMs)are veryimportantduetotheirextensiveuseinpre ventingandcuringmanydiseasesforhumans.Al thoughonlysomecompoundsmightberesponsible forpharmaceuticaleffects,traditionalChinese medicinesusuallycontaintoomanycomponentsandformaverycomplexsystem,whichmakesthe screeningandanalysisofbioactivecomponentsex tremelydifficult[1]comparedwiththoseofwesternmedicines.Whensuchcomplexsamplesareana lyzed,itiscommonthatdifferentcontentsof multi componentsandgreatd… 相似文献
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Determination of volatile components in cut tobacco with gas chromatography-mass spectrometry and chemometric resolution 总被引:2,自引:0,他引:2
Chromatography-mass spectrometry(GC-MS)was used to analyze the volatile components of cut tobacco samples with the help of heuristic evolving latent projections(HELP).After extracting with simultaneous distillation and extraction method,the volatile components in cut tobacco were detected by GC-MS.Then the obtained original two-dimensional data were resolved into pure mass spectra and chromatograms.The qualitative analysis was performed by similarity searches in the national institute of standards and technology(NIST)mass database with the obtained pure mass spectrum of each component and the quantitative results were obtained by calculating the volume of total two-way response.The accuracy of qualitative and quantitative results were greatly improved by using the two-dimensional comprehensive information of chromatograms and mass spectra.107 of 141 separated constituents in the total ion chromatogram of the volatile components were identified and quantified,accounting for about 88.01% of the total content.The result proves that the developed method is powerful for the analysis of complex cut tobacco samples. 相似文献