Development and Application of a Dual Detection Concept (Amperometry-Mass Spectrometry) for Capillary Electrophoresis

毛细管电泳双重检测概念（电流分析法-质谱法）的开发和应用

• 批准号: 441791263
• 负责人: Professor Dr. Frank-Michael Matysik
• 金额: --
• 依托单位: Institut für Analytische Chemie, Chemo- und Biosensorik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/441791263?language=en
• 关键词: Development; Application; Dual; Detection; Concept

The high complexity of samples in medical and environmental applications and the increasing number of analyses in shorter time-scales demand new developments of powerful instrumental analytical systems. Separation techniques coupled to dual detection methods are capable of generating a large amount of information in one run because of the separation of analytes and the combined data from both detection methods.In this project, a dual detection concept for hyphenation of capillary electrophoresis (CE) - a separation method based on the migration of charged species in an electrical field, which allows for short separation times and low consumption of samples and solvents - with amperometric detection (AD) and mass spectrometry (MS) is planned. AD is well suited for quantification in capillary electrophoresis due to its unmatched sensitivity at low amounts of sample as they occur in capillary electrophoresis. However, it is not possible to identify substances or to spot comigrations. In contrast, MS can identify unknown substances based on their mass spectra and corresponding molecular formulas. However, the limits of detection (depending on the analytes) obtained with CE-MS are typically in the range of 10-6 M which is about two magnitudes of order higher than currently obtained in CE-AD. With the newest generation of potentiostats the limits of AD can even be lowered. In addition, due to the complexity of electrospray ionization quantification has usually to be based on the use of isotope labelled standards, which can be expensive and are not always available. Thus, the CE-AD/MS concept provides complementary data and information.As both detectors cannot be placed one after the other due to their destructive properties, a new concept has to be developed to split the high voltage-driven flow through the separation capillary onto both detectors. The instrumental development of an optimized coupling device for CE-AD/MS should enable a precise control of both microfluidic flow streams. Ferrocene derivatives can serve as internal standards to calculate effective mobilities of the analytes. In this way an unambiguous assignment of AD and MS signals can be achieved even if migration times tend to shift.The amount of analyte in the sample can be quantified by AD, which is very sensitive and easy to handle, while substance identification and peak purity can be validated by MS to avoid false results. Additionally, due to the complementary detection principles, substances that cannot be detected with one detector can often be detected with the other so that a broader range of components in complex samples can be analyzed.Thus, the novel CE-AD/MS concept provides a high information density and universality so that it can contribute to the analysis of complex samples.

医学和环境应用中样品的高度复杂性以及在较短时间尺度内越来越多的分析要求开发新的强大的仪器分析系统。由于分析物的分离和两种检测方法的组合数据，分离技术与双检测方法耦合能够在一次运行中产生大量信息。在本项目中，毛细管电泳（CE）联用的双检测概念-一种基于带电物质在电场中迁移的分离方法，该方法允许短的分离时间和低的样品和溶剂消耗-与安培检测（AD）和质谱（MS）。AD非常适合于毛细管电泳中的定量，因为其在毛细管电泳中出现的低量样品下具有无与伦比的灵敏度。但是，无法识别物质或发现混合物。相比之下，MS可以根据其质谱和相应的分子式识别未知物质。然而，用CE-MS获得的检测限（取决于分析物）通常在10-6 M的范围内，这比目前在CE-AD中获得的检测限高约两个数量级。使用最新一代的恒电位仪，AD的极限甚至可以降低。此外，由于电喷雾电离的复杂性，定量通常必须基于使用同位素标记的标准品，这可能是昂贵的，并不总是可用的。由于两个检测器的破坏性，不能一个接一个地放置，因此必须开发一种新的概念，将高压驱动的流动通过分离毛细管分流到两个检测器上。用于CE-AD/MS的优化耦合装置的仪器开发应该能够精确控制两种微流体流动流。二茂铁衍生物可以作为内标物来计算分析物的有效迁移率。通过这种方式，即使迁移时间有偏移的趋势，也可以实现AD和MS信号的明确分配。样品中分析物的量可以通过AD进行定量，这非常灵敏且易于处理，而物质鉴定和峰纯度可以通过MS进行验证，以避免错误结果。此外，由于互补的检测原理，一种检测器检测不到的物质通常可以用另一种检测器检测到，从而可以分析复杂样品中更广泛的组分。因此，新的CE-AD/MS概念提供了高信息密度和通用性，从而有助于复杂样品的分析。