Analysis of the constituents in the rat plasma after oral administration of Yin Chen Hao Tang by UPLC/Q-TOF-MS/MS

A UPLC/Q-TOF-MS/MS method for analyzing the constituents in rat plasma after oral administration of Yin Chen Hao Tang (YCHT), a traditional Chinese medical formula, has been established. The UPLC/MS fingerprints of the samples were established first in vitro and in vivo, with 45 compounds in YCHT and 21 compounds in rat plasma after oral administration of YCHT were detected. Of the 45 detected compounds in vitro, 30 were identified, and all of the 21 compounds detected in rat plasma were identified either by comparing the retention time and mass spectrometry data with that of reference compounds or by mass spectrometry analysis and retrieving the reference literatures. Of the identified 21 compounds in rat plasma, 19 were the original form of compounds absorbed from the 45 detected compounds in vitro, 2 were the metabolites of the compounds existed in YCHT. It is concluded that a rapid and validated method has been developed based on UPLC-MS/MS, which shows high sensitivity and resolution that is more suitable for identifying the bioactive constituents in plasma after oral administration of Chinese herbal medicines, and provides helpful chemical information for further pharmacology and active mechanism research on the Chinese medical formula.

Characterization of linear epitope of the beta(2)-microglobulin via combination of MALDI-TOF-MS with immunoaffinity

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF-MS), in combination with immunoaffinity provided a powerful tool for determining epitope (antigenic determinant) in protein. The linear epitope of the beta(2)-microglobulin was characterized in the paper. The method as follows: at first beta(2)-microglobulin was digested by a proteolytic enzyme to produce an appropriate set of peptide fragments, then peptide fragments containing the linear epitope were selected and separated from the pool of peptide fragments by immunoprecipitation with the monoclonal antibody. The agarose beads were collected carefully after the reaction. Unbound peptides would be washed away, while the peptides containing the epitope would remain bound to the immobilized antibody after. the beads were washed several times with appropriate buffer. At last the masses of the bound peptides were identified directly by MALDI-TOF MS. Using Endoproteinase Glu-C Endoproteinase Lys-C and Trypsin in the experiment, the linear epitope of beta(2)-microglobulin was located within peptide fragment 59-69, that is, DWSFYLLYYTE.

MALDI-TOF-MS法对重组人内皮抑素蛋白分子质量测定

肿瘤的生长依赖于血管的生成,新生血管不仅为肿瘤生长提供必需的营养物质,而且为肿瘤细胞扩散提供了重要的途径[1].1997年哈佛大学的O'Reilly等[2]发现了一种内源性新血管生成抑制因子内皮抑素(Endostatin),显示出特异抑制激活的血管内皮细胞增殖和肿瘤新血管生成的生物学活性,其抗肿瘤作用具有高效、低毒、无耐药性的优点.

用MALDI-TOF-MS法测定重组人肿瘤坏死因子α衍生物

利用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF -MS)法测定了重组人肿瘤坏死因子α衍生物的分子质量 ,并对所得的结果进行了讨论 ,实验证明该法灵敏度高 ,重复性好 ,结果准确 ,是测定蛋白质分子质量的有效方法

用MALDI-TOF-MS法表征系列环状预聚体

应用基质辅助激光解吸电离飞行时间质谱 ( MALDI- TOF- MS)技术对系列环状预聚体进行了表征 ,分别确定了系列环状预聚体各自不同的聚合度 ,同时对它们的结构进行了确认 ,获得了满意的结果。实验结果表明 MALDI- TOF- MS是分析环状预聚体准确、快速工具之一

MALDI/TOF MS法测定蛇毒纤溶酶及磷脂酶A_2的分子量和纯度

目的： 分析测定长白山白眉蝮蛇蛇毒纤溶酶和磷脂酶A2 的分子量和纯度。方法与结果： 应用MALDI/TOF MS法测定纤溶酶的分子量为23333±90，磷脂酶A2的分子量为14000±20，相对偏差在0138%以内。结论： 应用此方法未检测到杂蛋白质谱峰的存在， 酶的纯度较好， 测得结果要比电泳法准确。MALDI/TOF MS提供了一种测定蛋白质药物纯度快速准确的新方法。

用MALDI-TOF-MS法快速测定天花粉蛋白分子量

采用MALDI TOF MS法快速测定了天花粉蛋白的分子量，并讨论和对比了三种不同基质对其影响，认为用基质芥子酸是最佳适宜条件。实验结果表明本方法优于其它传统的测定生物大分子分子量方法

MALDI-TOF-MS法用于谷脱甘肽S-转移酶分子量的测定

利用MALDI-TOF-MS法测定了谷胱甘肽S-转移酶的分子量,并讨论和对比了三种不同基质对其影响,认为用α-氰基-4-羟基肉桂酸(α-CHC)作基质是最佳适宜条件。实验结果表明本方法优于其它传统的测定生物大分子分子量方法。

酚醛环氧树脂的基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)表征

用基质辅助激光解吸电离飞行时间质谱（MALDI－TOF－MS）技术研究了F－46和JF－43型酚醛环氧树脂。获得了该类树脂的聚合度及其不同聚合度组分的分子结构；发现该类树脂中含有环氧氯丙烷的聚合物，给出了可能的分子结构。

5种E型环氧树脂的基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)表征

应用基质辅助激光解吸电离飞行时间质谱（ＭＡＬＤＩ－ＴＯＦ－ＭＳ）技术，研究了Ｅ－１２、Ｅ－３１、Ｅ－４２、Ｅ－４４和Ｅ－５１五种牌号环氧树脂。获得了该类树脂的聚合度及其不同聚合度所对应的分子结构；发现了该类树脂中有一定量的环氧氯丙烷的聚合物，并给出了可能的分子结构。