搜索结果: 1-15 共查到“化学 ESI/MS”相关记录20条 . 查询时间(0.156 秒)
为了给寡糖质量控制和分析研究提供方法参考，对1-（4-异丙基）苯基-3-甲基-5-吡唑啉酮(PPMP)衍生化试剂在液相色谱（HPLC）和电喷雾质谱（ESI-MS）技术分析寡糖中的应用进行研究。用PPMP试剂在氨水介质中对葡寡糖链进行衍生化，衍生化产物用RP-HPLC分离，ESI-MS分析。实验表明：在确定的衍生化条件下，PPMP和寡糖的衍生化主产物为单分子标记物，葡寡糖混合物的单分子PPMP衍生物...
用不同形态的镉培养液(氯化镉、硝酸镉、镉-EDTA、草酸镉和柠檬酸镉)对不同种类的蕨类植物(狗脊、舌厥、石松、瓦韦和石韦)进行培养。研究发现，镉在植物体不同部位的富集量是有差异的(富集量：根>茎>叶);对SEC-HPLC截取出的植物鳌合肽(PCs)研究表明，不同形态的镉能不同程度的诱发植物体中PCs的合成，从而PCs与Cd配位，降低镉的毒性，发现的配体主要为PC3，iso-PC3(βAla)和is...
Development of a UPLC-ESI-MS/MS Assay for 20(S)-Protopanaxadiol and Pharmacokinetic Application of Its Two Formulations in Rats
Pharmacokinetic Application Two Formulations Rats
2010/9/14
An ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed to investigate 20(S)-protopanaxadiol (PPD) pharmacokinetics in rats. Rat plasma s...
甘露糖磷酰氨基酸缀合物的ESI-MS研究
甘露糖磷酰胺缀合物 电喷雾质谱 裂解规律
2009/11/23
一系列全乙酰保护甘露糖-1-磷酰氨基酸酯缀合物的α构型和β构型异构体的ESI-MSn裂解规律研究表明, β构型异构体会出现一系列特征的m/z 433, 391, 371的碎片离子, 且［M-CH2CHCH3+Na］+碎片丰度较大. ［M-糖基+Na］+和［糖基+Na］+碎片相对丰度较小. α构型分子反之. 同时对全乙酰保护的［糖基+Na］+ m/z 353碎片离子进行三级碎裂, 其主要特征是消除C...
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 obta...
ESI-MS/MS法鉴别环肽非对映异构体和碎裂机理的研究
ESI mass spectrometry cyclic peptides diastereomer distinguishing diastereomer
2010/3/30
The discrimination of four pairs of cyclic peptide diastereomers were successfully achieved by ESI-MS. The ratio of ions’ abundance ratios between A and B isomers in MS/MS spectra was defined as a par...
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 diff...
The isoflavonoids from Iris tectorum were analyzed by electrospray ionization tandem mass spectrometry(ESI-MS/MS). Based on the information of pseudo molecular ions and daughter ions were obtained by ...
磷酰化肽酯及小肽与氨基酸相互作用的ESI-MS研究
ESI-MS N-phosphoryl dipeptides(or methyl esters) amino acids non-covalent weak interaction
2010/3/30
The non-covalent interaction between a series of N-diisopropylphosphoryl dipeptides(or methyl esters) (DPP) and amino acids was studied by ESI-MS. The results show that aromatic rings to form π–π conj...
Triterpene and saponin in Radix ilicis pubescentis were identificated by HPLC-MS. The samlpe was extracted with methanol, and analyzed by HPLC-IT-MS and HPLC-TOF-MS to obtain the positive-ion and nega...
利用片断合成法合成了具有DNA切割能力的六聚吡咯/丝组缀合物, 检测了该化合物的1H、13C NMR 和ESI-MS/ MS 图谱, 确证了该化合物的结构, 通过1H-1H COSY, HSQC，HMBC等2D NMR 技术对其1H 和13C NMR 数据进行了归属和解析, 并探讨了其ESI-MS/ MS 质谱裂解规律.
HPLC/ESI-MS法鉴定半枝莲乙酸乙酯组分中黄酮苷元类化合物
半枝莲 黄酮苷元 高效液相色谱 电喷雾质谱
2009/10/20
利用正离子模式电喷雾质谱研究了包括正黄酮、异黄酮、二氢黄酮、异二氢黄酮和黄酮醇在内的5个黄酮亚类苷元的质谱断裂碎片，并得到了能够区别鉴定这5类黄酮苷元的特征碎片离子。其中，2个CO的连续丢失可以看作异黄酮的特征断裂，[0,4B-H2O+H]+是二氢黄酮的特征碎片离子，黄酮醇和异二氢黄酮则主要发生0，2键和2，3键的断裂，分别形成特征的0,2A+和2，3B+碎片离子。在此基础上，利用高效液相色谱...
HPLC-ESI-MS/MS识别蓝莓提取物中的花青素和黄酮醇
花青素 黄酮醇 蓝莓 高效液相色谱-质谱联用 电喷雾离子化/串联质谱
2009/10/15
用高效液相色谱-电喷雾离子化串联质谱联用技术(HPLC-ESI-MS/MS)对蓝莓提取物中的黄酮类物质进行了分析, 可以快速地鉴定其主要成分为花青素和黄酮醇. 结构上的不同导致花青素和黄酮醇在紫外-可见光谱吸收、离子化以及裂解方式上都存在差异. 尽管花青素和黄酮醇在270 nm处都有吸收, 但两者分别在530和372 nm附近有特征吸收. 负离子模式下, 黄酮醇可以生成负离子和自由基负离子, 而正...
小蜡树中苯乙醇苷类化合物的ESI-MS/MS研究
fragmentation behavior phenylethanoid glycosides ESI-MS/MS negative ion mode
2009/4/7
The fragmentation behavior of phenylethanoid glycosides from Fraxinus sieboldiana were investigated
systematically by using ESI-MS/MS in negative ion mode. The fragmentation reaction of these compoun...
Using ESI-MS, adding different V:V methanol, study the conformation of Myoglobin at pH 5.6. The results showed that the concentration of methanol was higher to induce conformation similar and low char...