检索结果-南通市图书馆

A membrane separation technique for optimizing sample preparation of maldi-TOF ms detection

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2019年第1期30卷 95-98页

作者： Zengnan Wu Ning Xu Weiwei Li Jin-Ming Lin State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Key Laboratory of Microanalytical Methods and Instrumentation Department of Chemistry Tsinghua University

The performance of matrix-assisted laser desorption/ionization time of flight mass spectrometry(maldi-TOF-ms) is frequently compromised by the high limited of detection, heterogeneous distribution of matrix and analyte deposits and time-consuming drying time during the conventional drop drying procedure. Here, we describe a method based on membrane separation technology to assist in the drying of nanomaterials to rapidly make homogeneous sample spots and to enhance the mass signal. We demonstrate that the sample can be dried evenly in a few seconds and ms signal can be greatly optimized by using membrane separation technology. Enrichment with nanomaterials greatly enhances analyte signal strength while membrane separation method avoids the time-consuming requirements of searching for "sweet spots".

关键词： maldi-ms Membrane separation Nanomaterial Mastoparan Insulin Cytochrome C

提高maldi-ms测量溶菌酶分子量灵敏度的研究

在线全文

学校读者我要写书评

暂无评论

高等学校化学学报 2002年第12期23卷 2247-2249页

作者：石磊王勇刘志强刘淑莹中国科学院长春应用化学研究所

Sodium dodecyl sulfate(SDS) is a powerful solubilizing detergent which is often used during the separation of highly complex protein mixtures by one- or two-dimensional(2D) gel electrophoresis. Matrix-assisted laser desorption/ionization mass spectrometry(maldi-ms) is a widely used technique for mass spectrometric analysis of some protein molecules compared to other techniques. But the presence of SDS or some salts usually leads to signal deterioration when using maldi-ms. A method for using nitrocellulose membrane as the solid-phase carrier combined with n-octyl-β-D-glucopyranoside in the matrix highly enhances the sensitivity of the molecular mass determination of lysozyme. This technique has the advantage that the signal-to-noise of the molecular weight profile is improved compared with the mass spectrum and the profile is relatively easy to interpret.

关键词： maldi-ms 测量分子量灵敏度基质辅助激光解吸电离质谱溶菌酶硝酸纤维素膜

糖的基质辅助激光解吸/电离质谱(maldi-ms)研究

在线全文

学校读者我要写书评

暂无评论

高等学校化学学报 1998年第7期19卷 1090-1094页

作者：郝春雁马秀俐刘志强季怡萍刘淑莹刘长城孙允秀刘举正中国科学院长春应用化学研究所吉林大学化学系

通过糖类化合物３种常用基质ＭＡＬＤＩ－ＭＳ分析效果的比较以及寡糖和多糖正、负离子ＭＡＬＤＩ－ＭＳ谱的对比，找到了适合糖分析的基质２，５－ＤＨＢ，探讨了糖类化合物激光解吸／电离条件下形成离子的过程，指出了Ｎａ＋、Ｋ＋离... 详细信息

通过糖类化合物３种常用基质ＭＡＬＤＩ－ＭＳ分析效果的比较以及寡糖和多糖正、负离子ＭＡＬＤＩ－ＭＳ谱的对比，找到了适合糖分析的基质２，５－ＤＨＢ，探讨了糖类化合物激光解吸／电离条件下形成离子的过程，指出了Ｎａ＋、Ｋ＋离子在寡糖分子量测定中的重要作用，借助柱层析分离手段，成功地测出了分子量大于１００００的葡聚糖的分子量．

关键词： maldi-ms 寡糖多糖分子量测定葡聚糖糖类

基于maldi-ms技术的新基质大黄酸在代谢组学研究中的应用

在线全文

学校读者我要写书评

暂无评论

中国药科大学学报 2016年第6期47卷 727-733页

作者：叶慧王赟王琳徐小为吴梦秋曹国秀梁艳王广基中国药科大学药物代谢动力学重点实验室南京210009

基质辅助激光解析电离质谱(maldi-ms)是一项快速、高通量检测未知物质的新兴技术。然而,该技术对代谢物的检测分析往往被复杂的基质峰所干扰,限制了其在代谢组学领域的应用。研究发现,大黄酸能作为一种maldi新基质用于阳离子模式下代谢... 详细信息

基质辅助激光解析电离质谱(maldi-ms)是一项快速、高通量检测未知物质的新兴技术。然而,该技术对代谢物的检测分析往往被复杂的基质峰所干扰,限制了其在代谢组学领域的应用。研究发现,大黄酸能作为一种maldi新基质用于阳离子模式下代谢物的检测。首先运用大黄酸分析了生理学浓度下多种强、弱碱性代谢物的标准品,结果表明与传统基质比较,大黄酸能获得基本无基质峰干扰的质谱图。进一步将大黄酸运用于生物样本的分析,选取小鼠内容物作为模型样本,显示该基质可用于复杂生物样本的代谢组分析。最后考察大黄酸的maldi质谱成像能力,表明该基质可成功运用于小鼠肠段切片的代谢组原位成像。研究表明,大黄酸作为一种新型maldi基质,能可靠、高效地完成基于maldi-ms的代谢物检测及原位成像分析,对maldi-ms技术广泛运用于代谢组学研究具有推动作用。

关键词： maldi-ms 质谱成像基质大黄酸代谢组学

maldi-ms反应性基质选择性检测啤酒中低聚糖的创新实践

在线全文

学校读者我要写书评

暂无评论

实验技术与管理 2021年第6期38卷 67-71页

作者：姜丽艳闫国栋玲玲国新华吉林大学生命科学学院吉林长春130012 吉林大学化学学院吉林长春130012

糖类是啤酒中含量最丰富的营养物质之一,对啤酒泡沫的稳定性起着十分重要的作用。通过大学生创新训练项目开发并优化了maldi-ms反应性基质用于选择性检测啤酒中低聚糖的新方法,具有响应信号强、特异性检测等优点。利用贴近生活的实验研... 详细信息

糖类是啤酒中含量最丰富的营养物质之一,对啤酒泡沫的稳定性起着十分重要的作用。通过大学生创新训练项目开发并优化了maldi-ms反应性基质用于选择性检测啤酒中低聚糖的新方法,具有响应信号强、特异性检测等优点。利用贴近生活的实验研究,激发了学生的学习热情和实验兴趣,提高了学生的创新能力和科研素养。

关键词： maldi-ms 反应性基质低聚糖实践教学

Matrix-assisted laser desorption ionization mass spectrometry based quantitative analysis of cordycepin from Cordyceps militaris

在线全文

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2021年第4期11卷 499-504页

作者： Jian Chen Hai-Fang Li Guozhu Zhao Jin-Ming Lin Xiangwei He Beijing Advanced Innovation Center for Tree Breeding by Molecular Design College of Biological Science and TechnologyBeijing Forestry UniversityBeijing100083China Department of Chemistry Beijing Key Laboratory of Microanalytical Methods and InstrumentationMOE Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical BiologyTsinghua UniversityBeijing100084China

Cordycepin,which has great immunomodulatory activities such as anticancer,antifungal,antivirus,antileukemia and lipid-lowering ones,is the secondary metabolite of Cordyceps militaris(C.militaris).Liquid submerged fermentation is the common cultivation process to produce cordycepin.To optimize the fermentation process and improve production,monitoring the cordycepin secretion in the fermentation is essential.The measurement based on chromatography-mass spectrometry methods is generally involved in the complex sample pretreatments and time-consuming separation,so more rapid and convenient methods are required.Matrix-assisted laser desorption ionization mass spectrometry(maldi-ms)is more attractive for faster and direct detection.Therefore,maldi-ms detection combined with isotope-labeled internal standard was applied to the measurement of cordycepin content in the fermentation broth and mycelium.This method made accurate quantification of cordycepin in the range of 5-400μg/mL with a relative standard deviation of 5.6%.The recovery rates of fermentation samples after the 1,13,and 25 days were 90.15%,94.27%,and 95.06%,respectively.The contents of cordycepin in the mycelium and fermentation broth were 136 mg/g and 148.39 mg/mL on the 20 th culture day,respectively.The cordycepin secretion curve of the liquid fermentation of C.militaris was real-time traced over 25 days.

关键词： Cordycepin maldi-ms Isotope internal standard Quantitative analysis Liquid fermentation

Fast saccharide mapping method for quality consistency evaluation of commercial xylooligosaccharides collected in China

在线全文

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2021年第3期11卷 284-291页

作者： Yong Deng Cunwu Chen Lingxiao Chen Bangxing Han Shaoping Li Jing Zhao State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacaoChina Anhui Engineering Laboratory for Conservation and Sustainable Utilization of Traditional Chinese Medicine Resources West Anhui UniversityLu'anAnhuiChina

Due to the extensive use of xylooligosaccharides(XOS)as functional food ingredients,many inferior goods and even adulterants are generally found in the market,which may pose a health hazard to certain populations.Chromatography method such as high-performance liquid chromatography(HPLC)and high-performance thin-layer chromatography(HPTLC)is traditionally applied for the quality analysis of XOS.However,it is time consuming due to the prolonged separation and pre-or post-derivatization procedure.In this study,a fast saccharide mapping method based on matrix-assisted laser desorption/time-of-flight mass spectrometry(maldi-TOF-ms)was developed for the quality consistency analysis of 22 batches of XOS collected from different manufacturers in China.The time needed for saccharides analysis using maldi-ms was less than 30 min for one plate,at least 6 times faster than that by the traditional HPTLC chromatography method.In addition,maldi-ms possessed higher resolution for XOS with DP4-DP7 based on the difference of m/z,which is hardly separated using HPTLC.The results showed that XOS were present only in samples XY01-XY11,samples XY12-XY14 only consisted of hex oligosaccharides,and samples XY15-XY22 were free of oligosaccharides.These indicate that the quality consistency of XOS products in the China market was poor,which should be carefully investigated.

关键词： Xylooligosaccharides Saccharide mapping maldi-ms Quality control

Differential Proteomic Analysis of Neonatal Cardiomyocytes in Response to β-Adrenergic Receptor Stimulation

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2006年第3期22卷 319-323页

作者： LI Zi-jian LIU Ning LIU Zhi-qiang LIU Shu-ying HAN Qi-de ZHANG You-yi Institute of Vascular Medicine Peking University Third Hospital and Key Laboratory ofMolecular Cardiovascular Sciences Ministry of Education Beijing 100083 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

β-Adrenoceptors（β-ARs） play a critical role in regulating cardiac functions under both physiological and pathological conditions. To further explore the mechanisms through which β-ARs perform its actions, proteomic approaches were adopted to study the global protein patterns in cultured neonatal rat cardiomyocytes exposed to iseproterenol （ISO）. A modified method, ＂Mirror Images in One Gel＂, was used to improve the reproducibility and resolution power of two-dimensional electrophoresis. A 2-DE map with a good reproducibility was obtained in which 1281 ± 70 spots were detected and about 1191± 54 spots were matched, with an average matching rate of 92. 9%. Nine proteins with significant changes were identified by using peptide mass fingerprinting（PMF） data obtained vht maldi-ms.

关键词： Proteome Two-dimensional electrophoresis（2-DE） maldi-ms β-Adrenoceptor Cardiomyocyte

Enhanced Ionization of Phosphatidylcholines during maldi Mass Spectrometry Using DCTB as Matrix

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2012年第9期30卷 2091-2096页

作者：张莹陆豪杰 Department of Chemistry and Institutes of Biomedical Sciences Fudan UniversityShanghai 200433China

Phosphatidylcholines （PCs） are the most abundant phospholipids constituents of the cellular membrane, which exhibit a variety of biological functions. The distinct critical roles in cellular function make their analysis quite de- manding. Although maldi-ms is one of the most powerful tools for biomolecules identification, it is still limited to phospholipids studies. The ionization of phosphatidylcholines is insufficient, and signals of PCs are frequently confused and suppressed by matrix clusters occurring in the same mass range. As an alternative matrix, T-2-（3-（4-t-butyl-phenyl）-2-methyl-2-propenylidene） malononitrile （DCTB） was introduced to overcome these problems in our study. Specifically, the signal intensity of phosphatidylcholines from soybean was enhanced more than several ten-folds using DCTB during positive ion maldi-TOFms. Peak overlaps caused by the wide distri- butions of series fatty acid residues from phospholipids were separated by introducing cesium cation. The occurred mass shift of 131.90 Da between [M＋Cs]＋ and [M＋H]~ （＂M＂ represents the molecular weight of the corre- sponding neutral hosphatidylcholine） was approved to be helpful in the assignments of ambiguous peaks of PCs from soybean. For real sample analysis, employing cesium chloride as an auxiliary reagent successfully facilitated the profiling and characterizing of PCs extracted from mouse lung and egg yolk followed by analysis with maldi-TOFms using DCTB as matrix.

关键词： phosphatidylcholines matrix maldi-ms DCTB