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Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) was used to determine the structures of anhydroicaritin glycosides by the MS/MS experiments of anhydroicaritin glycosides and their methylated derivatives,With high accuracy FT-ICR-MS provides much information about the structures of compounds ,FT-ICR-MS shows the great potential application in the structural characterization of unknown compounds.  相似文献   
2.
Recently, capillary electrophoresis/electrospray ionization mass spectrometry (CE/ESI- MS) has been rapidly developed as a powerful analytical tool for charged species ranged from small molecules such as carboxylic acids1, phenolic compounds2, metal species3, tetramines4, herbicides5, drugs and drug metabolites6 to peptides and proteins7, 8. The ESI mode has proven to be sensitive, versatile and relatively easy to use in combination with CE. CE confers rapid analysis and efficient separ…  相似文献   
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Milk as a key element for infant nutrition represents the only source of feeding for newborns and infants, breast-feeding milk normally contains several bioactive proteins or peptides useful for the development of the immune system that protects infants from diseases. Osteopontin(OPN) plays a distinct role during the processes of lactation. Some studies on OPN isolated and purified from the human milk via HPLC on SCX and C4 columns adopted biological mass spectrometry. After digesting the purified OPN sampl...  相似文献   
4.
In recent years, increasing attention has been paid to “soft” photoionization (PI), which will potentially become a standard, universal ionization method. Tunable synchrotron vacuum ultraviolet (SVUV) light, a quasi-continuous light with good energy resolution and high photon flux, has proved an ideal source for “soft” PI in various research fields (e.g., combustion chemistry and molecular imaging).This review focuses on combinations of SVUV light with commonly used techniques (e.g., molecular-beam sampling, laser desorption, ion desorption, and thermal vaporization). These couplings have successful applications in flame chemistry, organic analysis, chemical imaging and aerosol mass spectrometry.  相似文献   
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Interactions of therapeutic drugs containing metals with proteins are known to exert a great impact on the mode of action of these compounds, including drug metabolism, delivery, cell processing, and targeting. Modern analytical techniques applied to proteomic studies of metallodrugs may improve our understanding of accompanying biochemical processes, which is essential for the efficiency of treatment, the proper dosing of established metal-based cancerostatic agents, and the design and development of new drugs. Such methods basically rely on the application of mass spectrometry (or a few alternative detection techniques) for species identification, characterization, quantification, and measuring the binding parameters, directly or after separation of free parent drug and protein-bound drug fractions, using the principles of electrophoresis, chromatography or ultrafiltration.This review focuses on the development and recent advances in the field of “metallodrug proteomics” from the implementation of advanced analytical methodologies. Also addressed are emerging issues of metallodrug binding toward cellular protein targets and within real-world biological samples.  相似文献   
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采用负离子模式的电喷雾傅立叶变换离子回旋共振质谱(ESI-FTICR-MS)对3个合成的肝素类化合物DHα、THα和THβ进行了全扫描一级谱和持续非共振辐照碰撞诱导解离(SORI-CID)串联质谱分析。样品浓度10μmol/L,流动泵注射直接进样。化合物中的磺酸胺和磺酸酯结构容易在一般电喷雾条件下发生分解,失去一个或者多个SO3,一级全扫描谱图中得到的谱峰均是带有单电荷或者双电荷的准分子离子峰。在串联质谱中,部分双电荷离子发生解离时,其二级谱图中子离子由单电荷子离子和双电荷子离子共同组成。通过对谱峰的局部放大,利用同位素峰的峰间距,能直接给出子离子的带电荷情况。同时,结合FTICRMS提供的高质量精度质谱数据,能够对所选取母离子的碎裂途径进行确认。离子质荷比测量的平均误差小于3.0×10-6。为结构复杂的类肝素化合物的质谱分析提供了借鉴。  相似文献   
7.
In this review sample preparation strategies used for crude oil digestion in last ten years are discussed focusing on further metals and non-metals determination. One of the main challenges of proposed methods has been to overcome the difficulty to bring crude oil samples into solution, which should be compatible with analytical techniques used for element determination. On this aspect, this review summarizes the sample preparation methods for metals and non metals determination in crude oil including those based on wet digestion, combustion, emulsification, extraction, sample dilution with organic solvents, among others. Conventional methods related to wet digestion with concentrated acids or combustion are also covered, with special emphasis to closed systems. Trends in sample digestion, such as microwave-assisted digestion using diluted acids combined with high-efficiency decomposition systems are discussed. On the other hand, strategies based on sample dilution in organic solvents and procedures recommended for speciation analysis are reported as well as the use of direct analysis in view of the recent importance for crude oil field. A compilation concerning sample preparation for crude oil provided by official methods as well as certified reference materials available for accuracy evaluation is also presented and discussed.  相似文献   
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复方板蓝根颗粒化学成分的质谱研究   总被引:2,自引:0,他引:2  
利用电喷雾多级串联质谱(ESI-MSn)和傅里叶变换离子回旋共振质谱(FT-ICR-MS)技术,对复方板蓝根颗粒经溶剂萃取后的95%(体积分数)醇提和水提部位的化学成分进行了系统研究,鉴定出多种氨基酸成分、糖及其衍生物、有机酸、氨基酸和单糖的梅拉德反应初级产物以及含硫化合物表告依春.该方法灵敏快速,适宜于中药提取物的化学成分分析.  相似文献   
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