Hoh Eunha, Mastovska Katerina
USDA Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 19038, USA.
J Chromatogr A. 2008 Apr 4;1186(1-2):2-15. doi: 10.1016/j.chroma.2007.12.001. Epub 2007 Dec 8.
Large volume injection (LVI) is a prerequisite of modern gas chromatographic (GC) analysis, especially when trace sample components have to be determined at very low concentration levels. Injection of larger than usual sample volumes increases sensitivity and/or reduces (or even eliminates) the need for extract concentration steps. Also, an LVI technique can serve as an interface for on-line connection of GC with a sample preparation step or with liquid chromatography. This article reviews the currently available LVI techniques, including basic approaches to their optimization and important real-world applications. The most common LVI methods are on-column and programmed temperature vaporization (PTV) in solvent split mode. Newer techniques discussed in this article include direct sample introduction (DSI), splitless overflow, at-column, and "through oven transfer adsorption desorption" (TOTAD).
大体积进样（LVI）是现代气相色谱（GC）分析的一个前提条件，尤其是当痕量样品组分必须在极低浓度水平下进行测定时。进样比通常更大的样品体积可提高灵敏度和/或减少（甚至消除）对提取物浓缩步骤的需求。此外，大体积进样技术可作为气相色谱与样品制备步骤或液相色谱在线连接的接口。本文综述了目前可用的大体积进样技术，包括其优化的基本方法和重要的实际应用。最常见的大体积进样方法是柱上进样和溶剂分流模式下的程序升温汽化（PTV）。本文讨论的较新技术包括直接进样（DSI）、不分流溢流、柱上和“通过柱箱转移吸附解吸”（TOTAD）。
