Attogram-level detection and relative sensitivity of strong electrophores by gas chromatography with electron capture detection
Attogram-level detection and relative sensitivity of strong electrophores by gas chromatography with electron capture detection
复制标题
采用电子捕获检测的气相色谱法对强电泳进行阿克级检测和相对灵敏度
DOI：
10.1021/ac00240a029
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发表时间：
1982
影响因子：
7.4
通讯作者：
R. Giese
中科院分区：
文献类型：
--
作者：
J. Corkill;M. Joppich;S. Kuttab;R. Giese
一些不同化合物（其中大多数是强电子吸收剂）的峰面积响应是通过带有电子捕获检测器的气相色谱法（GCECD）测量的。最敏感的化合物是衍生的碘甲腺原氨酸，其基本上比林丹敏感20倍。选择V，N-二五氟苯甲酰基五氟苯胺（一种稍微不太敏感但更易挥发的物质）来确定检测限。该值为 90 ag (1.6 X 10~ 19 mol)，主要是由于其在痕量水平上的响应异常增加。据报道，这将 GC-ECD 的灵敏度提高了 100 倍。蒸气状态的电泳团是吸收热电子的分子或取代基 (1, 2)。这种类型的电子吸收发生在气相色谱（GC-ECD，例如参考文献3）和液相色谱（4）以及负化学电离质谱（5、6）中的电子捕获检测器中。相对较少的分子同时具有挥发性和强电电性。之前已经研究过不同电泳的相对响应，如已综述 (3,7,8)，但这项工作可以在几个方面进行扩展。在任何特定的研究中，通常只检查有限种类的电泳结构。某些有趣的分子未包括在内，例如衍生化的碘甲状腺原氨酸 (9)，或者未与其他电泳分子进行比较，例如 flophemesyl (7)。涉及各种类型的 EC 检测器和 GC-ECD 条件，这会影响响应 (8)。因此，在一组恒定和典型条件下进行强电泳的灵敏度研究是有用的。这里使用的条件是毛细管气相色谱仪，配有熔融石英柱和恒流、变频、小体积 ECD。本研究的目的是确定 GC-ECD 最敏感且易挥发的结构类型，以指导未来改进 GC-ECD 衍生剂及相关技术的开发。这里得出的主要结论是：(1) 衍生化的碘甲腺原氨酸是所检测的化合物中最敏感但挥发性最小的，(2) flophemesyl 基团，它具有
The responses as peak areas of some divergent compounds, most of which are strong electron absorbers, are measured by gas chromatography with electron capture detection (GCECD). The most sensitive compounds are derivatlzed lodothyronines, which are essentially 20-fold more sensitive than lindane./V,/V-Dlpentafluorobenzoylpentafluoroanlline, a somewhat less sensitive but more volatile substance, was selected for determination of a detection limit. The value was 90 ag (1.6 X 10~ 19 mol), largely due to an anomalous Increase In Its response at the trace level. This Increases the reported sensitivity of GC-ECD by 100-fold.Electrophores in the vapor state are molecules or substit-uents which absorb thermal electrons (1, 2). This type of electron uptake takes place in the electron capture detector in both gas chromatography (GC-ECD, eg, ref 3) and liquid chromatography (4), and also negativechemical ionization mass spectrometry (5, 6). Relatively few molecules are both volatile and intensely electrophone. The relative response of different electrophores has been studied previously, as has been reviewed (3, 7, 8), but this work can be extended in several respects. Only a limited variety of electrophoric structures were often examined in any particular study. Certain interesting molecules were not included, such as the derivatlzed iodothyronines (9), or were not com-pared with otherelectrophores, such as flophemesyl (7). Various types of EC detectors and GC-ECD conditions were involved, which can influence the response (8). Thus, it is useful to conduct a sensitivity study of strong electrophores under a set of constant and typical conditions. The conditions employed here are capillary GC with a fused silica column and a constant current, variable frequency, small volume ECD. The purpose of this study is to define the types of structures which are most sensitive as well as volatile by GC-ECD, in order to guide the future development of improved derivatizing agents for GC-ECD and related techniques. The main conclusions reached here are that (1) the derivatized iodothyronines are the most sensitive but least volatile of the compounds examined,(2) the flophemesyl group, which has