CAPACITOR-BASED INTERFACE FOR MASS SPECTROMETRY

描述(改编自申请人的摘要)：本报告的目标 项目是开发一种超灵敏的液态MS界面，基于 圆柱形电容电离(CCI)技术 在申请人的实验室中研发。新的CCI接口不支持 需要在喷头周围施加外部电场，例如 通常使用的金属针和对电极布置 电喷雾电离(ESI)。样品液体被带入 电容器，而不是主要在喷头。然后这些带电的液体 可以喷洒到可能具有各种压力和 目前有电力状况。新的设计将限制电晕放电， 并允许人们在喷雾附近放置一个离子聚焦去溶装置 尖端，它可以低于大气压。这种新设计将会有 与现有的ESI源相比，离子传输效率要好得多。 对于大多数生物来说，它对溶剂的依赖性更低，耐盐性更强 样品，并将在正负离子模式下工作得同样好。喜欢 电喷雾，这一新设备将适用于多种类型的 仪器，包括四极，四极离子陷阱，傅里叶变换， 和飞行时间ms观察到的信号/噪声改善 生物分子预计将是10到500倍。生成的初步数据 使用CCI前端，使用其他出厂标准的芬兰加热 毛细管接口，表明大约500倍于 负离子注入分析的浓度检出限 二磷化脂A，流速50nL/min。最大的影响 生物分子的痕量分析将感受到生物医学的研究 难以喷洒，或具有相对较高的检测下限， 利用现有的电喷雾技术。这将包括许多生物学上的 阴离子，或在气相中容易形成阴离子的化合物，如 糖脂、碳水化合物、核酸、酸性蛋白质和酸性 多肽。阳离子的分析也有望得到改进。 生物起源的。

DESCRIPTION (Adapted from the applicant's abstract): The goal of this project is to develop an ultra sensitive liquid phase MS interface, based on the cylindrical capacitor ionization (CCI) technique which has recently been developed in the applicant's laboratory. The new CCI interface does not require an externally applied electric field around the spray tip, such as the metal needle and a counter electrode arrangement normally employed in electrospray ionization (ESI). The sample liquid is charged inside the capacitor instead of primarily at the spray tip. This charged liquid then can be sprayed into a space which may have a variety of pressure and electrical conditions present. The new design will limit corona discharge, and will allow one to put an ion focusing desolvation device near the spray tip, which can be below atmospheric pressure. This new design will have much better ion transmission efficiency relative to existing ESI sources. It will be less solvent dependent and more salt tolerant for most biological samples and will work equally well in positive and negative ion mode. Like electrospray, this new device will be applicable to many types of instruments, including quadrupole, quadrupole ion trap, Fourier transform, and time-of-flight MS. The signal/noise improvements observed for biomolecules are expected to be 10 to 500-fold. Preliminary data generated using a CCI front end, with an otherwise factory standard Finnigan heated capillary interface, indicated roughly a 500-fold improvement in concentration detection limits for the negative ion infusion analysis of diphosphorylated lipid A, at a flow rate of 50 nL/min. The greatest impact on biomedical research will be felt in the trace analysis of biomolecules that are difficult to spray, or that have relatively high detection limits, using existing electrospray technology. This would include many biological anions, or compounds that readily form anions in the gas phase, such as glycolipids, carbohydrates, nucleic acids, acidic proteins and acidic peptides. Improvements are also expected for the analysis of positive ions of biological origin.