薄层色谱与质谱联用的研究进展

薄层色谱(TLC)是一类非常实用的液相色谱方法，由于其装置简单、操作便捷、灵活、通量高、成本低，以及样品前处理简单等优点，在许多行业的检测中都有广泛的应用并扮演着重要的角色。随着现代检测技术的不断发展以及各种检测技术综合应用程度的加深，薄层色谱与质谱的联用(TLC-MS)也成为这一方法的重要发展方向。随着我国医药、食品、科学仪器等事业的不断发展和升级，相信薄层色谱-质谱联用技术可以起到更好的作用，并迎来发展的契机。该综述将目前薄层色谱-质谱的联用形式分为3类，一是接口仪器的间接联用，二是质谱对薄层板的原位检测，三是质谱对薄层分离过程的实时监测，并按此分类对典型的联用形式进行了总结和简要描述。随着薄层色谱-生物自显影技术的广泛使用，薄层色谱与质谱联用的技术方法极大地提高了食品、药用生物活性物质的研发效率。目前，薄层色谱与质谱联用发展的主要瓶颈是“即插即用”型部件的设计和商品化。具有实时监测功能，同时又兼备灵活扫描功能和高通量特点的TLC-MS技术也很令人期待。此外，不同种类TLC-MS解吸-电离技术的对比研究也是有待讨论的应用问题。

Advances in thin layer chromatography coupled with mass spectrometry technology

Thin layer chromatography (TLC) is a very useful liquid chromatography approach. The simple device, convenient operation, versatility, high throughput capabilities, low cost, and simple sample pretreatments make it widely employed in various fields. In recent years, TLC-MS has become one of the most prominent trends for this technology as developments of modern analytical technology and comprehensive application of different approaches. With the development and upgrading of medicine, food, and scientific instrument industries, it is believed that TLC-MS technology should play a better role and obtain an opportunity for development. This study reviewed TLC-MS interface technologies (most of which are in recent 10 years) based on more than 150 studies and classified these TLC-MS technologies as three strategies. The first is indirect coupling using commercially available interface instruments. The second is TLC-in-site detection directly with special MS ion source devices like fast-atom-bombardment desorption ionization, matrix-assisted laser desorption ionization, surface-assisted laser desorption ionization, electrospray-assisted laser desorption ionization, laser-induced acoustic desorption/electrospray ionization, electrostatic-spray ionization, easy ambient sonic-spray ionization, desorption sonic spray ionization, ionization using “desorption/ionization resource”, ionization using “molecular ionization-desorption analysis source”, multiwavelength laser desorption ionization, ionization using flowing afterglow-atmospheric pressure glow discharge, ionization low-temperature plasma probe, desorption/ionization induced using neutral clusters, ionization using inductively coupled plasma and so on. These MS analyses are performed after TLC development, thus, the relative position of the chromatographic bands on TLCs is invariable, and this analysis can be regarded as static detection, though flexible travel stages or conveyor belts can be introduced to move TLC plates. The third strategy is to monitor TLC run using MS in real-time just as the monitor employed in HPLC, in which the chromatographic bands are still moving. This strategy is generally run on forced-flow TLC techniques and is less examined. The typical coupling technologies (especially appeared in recent ten years) are summarized and briefly described in this study. TLC-MS has greatly enhanced the research efficiency of bioactive substances for food and drugs due to the widespread usage of TLC-bioautography technology. Nowadays, the main bottleneck in the development of TLC-MS is the design and commercialization of “plug and play” components. The high-throughput and real-time monitoring TLC-MS technology with flexible scanning functions is also expected. Furthermore, the comparative studies of different kinds of desorbing-ionizing technologies are also application problems for further discussion.