Department of Manufacturing and Civil Engineering, Norwegian University of Science and Technology, 2815 Gjøvik, Norway.
Int J Mol Sci. 2022 Aug 25;23(17):9642. doi: 10.3390/ijms23179642.
The selective sensing of gaseous target molecules is a challenge to analytical chemistry. Selectivity may be achieved in liquids by several different methods, but many of these are not suitable for gas-phase analysis. In this review, we will focus on molecular imprinting and its application in selective binding of volatile organic compounds and atmospheric pollutants in the gas phase. The vast majority of indexed publications describing molecularly imprinted polymers for gas sensors and vapour monitors have been analysed and categorised. Specific attention was then given to sensitivity, selectivity, and the challenges of imprinting these small volatile compounds. A distinction was made between porogen (solvent) imprinting and template imprinting for the discussion of different synthetic techniques, and the suitability of each to different applications. We conclude that porogen imprinting, synthesis in an excess of template, has great potential in gas capture technology and possibly in tandem with more typical template imprinting, but that the latter generally remains preferable for selective and sensitive detection of gaseous molecules. More generally, it is concluded that gas-phase applications of MIPs are an established science, capable of great selectivity and parts-per-trillion sensitivity. Improvements in the fields are likely to emerge by deviating from standards developed for MIP in liquids, but original methodologies generating exceptional results are already present in the literature.
对分析化学来说，选择性地感应气态目标分子是一项挑战。在液体中，可以通过几种不同的方法实现选择性，但其中许多方法不适合气相分析。在这篇综述中，我们将重点介绍分子印迹及其在选择性结合挥发性有机化合物和大气污染物方面的应用。对描述用于气体传感器和蒸气监测器的分子印迹聚合物的绝大多数索引出版物进行了分析和分类。然后特别关注了对这些小挥发性化合物进行印迹的灵敏度、选择性和挑战。在讨论不同的合成技术时，我们区分了致孔剂（溶剂）印迹和模板印迹，并分别考虑了每种技术在不同应用中的适用性。我们得出的结论是，在气体捕获技术中，致孔剂印迹（过量模板合成）具有很大的潜力，并且可能与更典型的模板印迹相结合，但后者通常仍然更适合对气态分子进行选择性和灵敏检测。更一般地说，已经可以得出结论，MIP 在气相中的应用是一门成熟的科学，具有很高的选择性和万亿分之一的灵敏度。通过偏离为液体中的 MIP 开发的标准，有望在这些领域取得改进，但文献中已经存在产生特殊结果的原始方法。
