272 resultados para ESI-MS

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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采用高效液相色谱与电喷雾质谱联用技术,对生附片的化学成分进行了系统的研究.并辅以提取离子色谱方法.发现微量的化学成分.通过保留时间,质荷比及多级串联质谱数据,共鉴定了48个成分,其中双酯型生物碱8个,单酯型生物碱7个,脂型生物碱29个.其中双酯型生物碱是生附片中的主要成分,而单酯型和脂型生物碱的含量和种类较少.

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目的:通过HPLC、ESI-MS指纹图谱对中药西洋参与北沙参进行鉴别。方法:利用HPLC和ESI-MS技术,优化西洋参、北沙参提取物的色谱和质谱分离分析条件,建立二者HPLC、ESI-MS指纹图谱。结果:确定出西洋参与北沙参HPLC的各色谱峰相对保留时间;根据MS图中各成份的m/z值,确定相应成分的分子量。二者的液相色谱和质谱指纹图谱完全不同。结论:通过HPLC、ESI-MS指纹图谱可以完全鉴别中药西洋参与北沙参,方法简单准确,重现性好,具有实用价值。

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对12批不同来源的刺五加叶提取物进行指纹图谱研究,并利用ESI-MS指纹图谱鉴别刺五加叶与山楂叶。分别采用高效液相色谱(HPLC-UV)和电喷雾电离质谱(ESI-MS)测定12批不同来源的刺五加叶提取物,利用ESI-MS技术测定刺五加叶与山楂叶提取物,得到了分离度、精密度和重现性均较好的刺五加叶HPLC-UV及ESI-MS指纹图谱;同时,利用刺五加叶与山楂叶ESI-MS指纹图谱的差异,成功鉴别了二者,可为刺五加叶药材的质量控制提供参考。

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ESI-MS was used to optimize the Ephedra sinica refinement. The ratio of honey to drug is 20/100, and the ratio of water to honey is 1/2. The toast temperature is 80 ℃, and the toast time is 2 h. The change of Ephedra sinica after processing was given.

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目的:考察大黄、黄柏、赤芍炮制前后化学成分在质和量方面的变化,以探讨中药的炮制机理。方法:利用电喷雾质谱法(ESI-MS)和高效液相色谱法(HPLC-UV),对大黄、黄柏、赤芍炮制前后的化学成分进行详细研究。质谱:电喷雾电离源(ESI),加热毛细管温度为200℃,喷雾电压为4.5kV;液相色谱:色谱柱为Agilent Zorbax C18柱(4.6mm×150mm,5μm),柱温均为28℃。结果:大黄经酒制和醋制后,其化学成分的含量变化较大;黄柏经酒制后巴马汀的含量略有增加,而小檗碱的含量呈下降趋势;盐制对于黄柏的化学成分几乎无影响;赤芍经酒制和炒制后,芍药苷的含量都呈下降趋势。结论:不同炮制方法对化学成分的影响不同,为进一步阐明中药材炮制入药的科学内涵提供了实验依据。

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Sialic acid and lysine as an internal standard substance,the ESI-MS fingerprinting of extracts of Compound Indigowoad Root Granule which from different origin was studied.The fingerprinting was obtained with better precision and reproducibility.This work can provide a reference for the quality control of Compound Indigowoad Root Granule.

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ESI-MS analytical method was employed to study extracts of unprocessed and processed Radix Paeoniae alba.The results of the experiments prove that different processed methods is making a certain different influence on the contents of chemiacl components in Radix Paeoniae alba.This method is simple and accurate.It can be used for analyse of Traditional Chinese Medicine(TCM).

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To study the content variation of ginsenosides and alkaloids during combination of ginseng with veratrum nigrum, the ginsenosides and alkaloids in the decoction of ginseng with veratrum nigrum were analyzed and compared by high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) and electrospray ionization-mass spectrometry (ESI-MS). In the compatible decoction, eight ginsenosides and eight alkaloids. were detected, and the contents of six ginsenosides were found to be reduced, on the contrary, the contents of six alkaloids were increased. During combination of ginseng with veratrum nigrum, the contents of ginsenosides were reduced and those of the toxic alkaloids were increased. From the chemical point of view, the traditional theory is right that ginseng and veratrum nigrum are incompatible with each other.

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A novel labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) coupling to liquid chromatography with electrospray ionization mass spectrometry for the detection of carbohydrates from the derivatized rape bee pollen samples is reported. Carbohydrates are derivatized to their bis-NMP-labeled derivatives. Derivatives showed an intense protonated molecular ion at m/z [M+H](+) in positive-ion detection mode. The mass-to-charge ratios of characteristic fragment ions at m/z 473.0 could be used for the accurately qualitative analysis of carbohydrates. This characteristic fragment ion is from the cleavage of C2-C3 bond in carbohydrate chain giving the specific fragment ions at m/z [MH-CmH2m+1Om-H2O](+) for pentose, hexose and glyceraldehydes and at m/z [MH-CmH2m-1Om+1-H2O](+) for alduronic acids such as galacturonic acid and glucuronic acid (m = n - 2, n is carbon number of carbohydrate). No interferences for all aliphatic and aromatic aldehydes presented in natural environmental samples were observed due to the highly specific parent mass-to-charge ratio and the characteristic fragment ions. The method, in conjunction with a gradient elution, offered a baseline resolution of carbohydrate derivatives on a reversed-phase Hypersil ODS-2 column. The carbohydrates such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose and fucose can successfully be detected.

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A new labeling reagent, 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP), coupling with liquid chromatography (LC) with electrospray ionization mass spectrometry (ESI-MS) for the detection of carbohydrates from a famous Tibetan medicine is reported. Carbohydrates were derivatized to their bis-NMP-labeled derivatives. The method, in conjunction with a gradient elution, offered a baseline resolution of carbohydrate derivatives on a reversed phase Hypersil ODS-2 column. The carbohydrates such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose, and fucose could be successfully detected by UV and ESI-MS. Derivatives showed intense protonated molecular ion at m/z [M+H]+ in positive ion mode. The mass to charge ratios of characteristic fragment ions at m/z 473.0 could be used for the accurately qualitative identification of carbohydrates; this characteristic fragment ion was from the cleavage of C2-C3 bond in the carbohydrate chain giving the specific fragment ions at m/z [MH-CmH2m+1Om-H2O](+) for pentose, hexose, and glyceraldehydes, and at m/z [MH-CmH2m-1Om+1-H2O](+) for alduronic acids, such as galacturonic acid and glucuronic acid (m=n-2, n is carbon atom number of carbohydrate). Compared with the traditional 1-phenyl-3-methyl-5-pyrazolone (PMP) reagent, currently synthesized NMP show the advantage of higher sensitivity to carbohydrate compounds with UV and ESI-MS detection.

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A monolithic enzymatic microreactor was prepared in a fused-silica capillary by in situ polymerization of acrylamide, glycidyl methacrylate (GMA) and ethylene dimethacrylate (EDMA) in the presence of a binary porogenic mixture of dodecanol and cyclohexanol, followed by ammonia solution treatment, glutaraldehyde activation and trypsin modification. The choice of acrylamide as co-monomer was found useful to improve the efficiency of trypsin modification, thus, to increase the enzyme activity. The optimized microreactor offered very low back pressure, enabling the fast digestion of proteins flowing through the reactor. The performance of the monolithic microreactor was demonstrated with the digestion of cytochrome c at high flow rate. The digests were then characterized by CE and HPLC-MS/MS with the sequence coverage of 57.7%. The digestion efficiency was found over 230 times as high as that of the conventional method. in addition, for the first time, protein digestion carried out in a mixture of water and ACN was compared with the conventional aqueous reaction using MS/MS detection, and the former solution was found more compatible and more efficient for protein digestion.