Chiral Metal–Organic Framework Films with Ordered Macropores for Enantioselective Analysis of Proteins

• Published in: Analytical chemistry (Washington) 2024-10, Vol.96 (43), p.17280-17289
• Main Authors: Yang, Ji, Song, Qinyi, Zhang, Tong, Yan, Yilun, Yuan, Chen, Cui, Yong, Hou, Xiandeng
• Format: Article
• Language: English
• Subjects: analytical chemistry; Chirality; coordination polymers; crystal structure; Crystallization; Dielectric barrier discharge; Diffusion barriers; Enantiomers; enantioselectivity; energy use and consumption; films (materials); fluorescence; Harnesses; liquids; macropores; Mass transfer; Metal-organic frameworks; Molecular structure; Nanospheres; optical isomerism; Polystyrene; Polystyrene resins; polystyrenes; porous media; Power consumption; Protein structure; Proteins; Sensors; Thin films
• ISSN: 0003-2700; 1520-6882; 1520-6882
• DOI: 10.1021/acs.analchem.4c03558

Chiral film-based sensors show great promise for discriminating between enantiomers due to their miniaturization and low power consumption. However, their practical use is hindered by the trade-off between enantioselectivity and mass transfer capability, especially concerning biomacromolecules such as proteins. In this work, we present an effective and straightforward method for creating highly organized macropores within crystalline chiral metal–organic framework (CMOF) films. This approach harnesses the shaping influence of a polystyrene nanosphere template and the crystallization induced by the liquid dielectric barrier discharge plasma. The resultant highly ordered macro–microporous structures improve mass diffusion and access to chiral active sites in the hierarchical CMOF films. Coupled with their inherent chirality, strong fluorescence emission, high crystallinity, and exceptional stability, these attributes endow these CMOF films with enhanced sensing capabilities for chiral molecules. Particularly, the macro–microporous structure facilitates efficient protein recognition, overcoming a significant challenge encountered by MOFs due to protein dimensions surpassing MOF pore sizes. These films exhibit increased enantioselectivity, better limits of detection, and wider linear ranges compared with purely microporous CMOF films. This study thus provides a powerful synthetic approach for hierarchical CMOF films, addressing the limitations of traditional thin film sensors and opening an avenue for efficient chiral sensing of large biomacromolecules.