Centre for Surface Chemistry and Catalysis, Department of Microbial and Molecular Systems, University of Leuven , Celestijnenlaan 200F, Post Box 2461, 3001 Heverlee, Belgium.
Molecular Imaging and Photonics, Department of Chemistry, University of Leuven , Celestijnenlaan 200F, Post Box 2404, 3001 Heverlee, Belgium.
Anal Chem. 2017 Apr 18;89(8):4480-4487. doi: 10.1021/acs.analchem.6b04510. Epub 2017 Mar 30.
The development of novel molecular sieves opens opportunities in the development of more sensitive analytical devices. In this paper, metal organic frameworks (MOFs), specifically ZIF-8 and ZIF-93, are grown on fiber optic based surface plasmon resonance (FO-SPR) sensors. FO-SPR has enabled sensitive sensing capabilities in biomedical settings and the addition of an MOF coating opens the way for the sensing of volatile organic compounds (VOCs) in gaseous media. FO-SPR probes were homogeneously functionalized with ZIF-8 and ZIF-93 in each case using two different precursor solutions to obtain a sequential nucleation and growth phase. The difference in MOF nucleation and growth kinetics of the two solutions was directly monitored by the FO-SPR system. The two established MOF-FO-SPR sensors were then subjected to sensing experiments with several alcohol vapors to establish their sensing capabilities. Vapors with mPa partial pressures, ppm concentrations, could successfully be detected, e.g., an LOD of 2.5 ppm for methanol detection was acquired. The difference in recognition behavior of the hydrophobic ZIF-8 and more hydrophilic ZIF-93 recognition layers can be exploited to yield qualitative information regarding the vapor composition.
新型分子筛的开发为更灵敏的分析器件的发展提供了机会。本文在光纤基表面等离子体共振（FO-SPR）传感器上生长了金属有机骨架（MOFs），特别是 ZIF-8 和 ZIF-93。FO-SPR 已经实现了在生物医学环境中的灵敏传感能力，而 MOF 涂层的添加为检测气态介质中的挥发性有机化合物（VOCs）开辟了道路。FO-SPR 探针使用两种不同的前体溶液均匀地功能化 ZIF-8 和 ZIF-93，以获得顺序成核和生长阶段。FO-SPR 系统直接监测两种溶液中 MOF 成核和生长动力学的差异。然后，将这两种已建立的 MOF-FO-SPR 传感器用于几种醇蒸气的传感实验，以确定其传感能力。可以成功检测到具有 mPa 分压、ppm 浓度的蒸气，例如，甲醇检测的检出限为 2.5 ppm。疏水性 ZIF-8 和更亲水性 ZIF-93 识别层的识别行为的差异可用于提供有关蒸气组成的定性信息。
