【作者】 徐松云；

【导师】 邹汉法；

【作者基本信息】 中国科学院研究生院（大连化学物理研究所） ， 分析化学， 2006， 博士

【摘要】 DIOS-MS技术在低分子量范围内克服了有机基质离子信号的干扰,实现了对小分子化合物和肽段的分析。大多数酶的底物都为小分子化合物,采用DIOS-MS技术检测酶催化底物生成的产物,可以监测酶的催化活性。胰蛋白酶修饰的多孔硅晶片对蛋白的原位酶解和原位肽谱分析提供了一个快速的和灵敏的工具。在对蛋白细胞色素C和牛血清白蛋白的鉴定上,取得了良好的序列覆盖度。亚胺二乙酸衍生的多孔硅表面可以对含有干扰物如尿素和表面活性剂的蛋白质样品进行预处理,通过清洗其表面,从而实现对蛋白质分子的MALDI质谱分析。此外,衍生化的多孔硅表面还可以转化为铁离子衍生的多孔硅表面,能从磷酸化蛋白酶解产物特异性地和选择性地纯化和富集磷酸化肽段。我们筛选出应用于MALDI分析的新基质3, 4-二氨基苯基苯甲酮,新基质对样品溶液中的污染物如盐酸胍和尿素表现出相对较好的抗干扰能力。此外, 3, 4-二氨基苯基苯甲酮在MALDI质谱分析中能有效抑制金属离子的加和现象。通过电弧法制备的多壁碳纳米管首次用作MALDI基质,用于代替有机基质检测样品分子,发展了碳纳米管上的解吸离子化飞行时间质谱技术分析小分子化合物。在脉冲激光的照射下,碳纳米管充当有机基质吸收能量,然后传递给样品分子,成功实现了对小肽,药物,糖类化合物和核苷类小分子化合物的分析。该方法为MALDI质谱在小分子化合物分析中的应用提供了新的途径。更多还原

【Abstract】 Because DIOS mass spectrometry presents little interference for the analysis of small molecules in the low-mass range, it is easy to monitor the digestion product formation of substrate with enzymatic reaction, and thereby to measure activity of the immobilized enzyme. Furthermore, a method for peptide mapping analysis by in-situ digestion of proteins on the porous silicon surface modified by enzyme trypsin, combined with matrix-assisted laser desorptio/ionization time-of-flight mass spectrometry has been developed. Good sequence coverage could be obtained for proteins of cytochrome C and BSA.Iminodiacetic acid (IDA)-1, 2-epoxy-9-decene modified porous silicon surface allows the removal of the contaminants in samples prior to MALDI mass spectrum analysis by simply washing the porous silicon surface. The carboxylic end groups on porous silicon can be used to selectively bind and concentrate target species in the sample solutions. Furthermore, the IDA-derivatized porous silicon can be transferred to Fe3+-IDA-derivatized porous silicon when needed, and the obtained porous silicon surface can specifically trap and effectively concentrate phosphopeptides from the tryptic digest of phosphoprotein and further analyzed by MALDI MS.Herein, a new MALDI matrix, 3, 4-diaminobenzophone (DABP), has been foundwith high tolerance against contaminants in sample solution for MALDI MS analysis. Furthermore, it has been found that this matrix can also effectively suppress the cation ion adduction of the peptides in the presence of high concentrations of metal ions in sample solution.Analysis of low molecular weight compounds with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) has been developed by using carbon nanotube obtained from coal by arc discharge as matrix. The carbon nanotube matrix functions as substrate to trap analytes of peptides, organic compounds andβ-cyclodextrin deposited on its surface. It has been found that carbon nanotube can transfer energy to analytes under laser irradiation, which makes analytes to be well desorbed/ionized. It is believed that this work will open a new field for applications of carbon nanotubes.更多还原