We herein describe novel amine-grafted metal–organic frameworks (MOFs) as a promising alternative to natural peroxidase enzyme and their applications for a fluorescent assay of choline (Cho) and acetylcholine (ACh). Among diverse amine-functionalized MOFs, N,N,N′,N′-tetramethyl-1,4-butanediamine (TMBDA)-functionalized MIL-100(Fe) (TMBDA-MIL-100(Fe)) exhibited the highest peroxidase activity by developing intense fluorescence from Amplex UltraRed (AUR) in the presence of H₂O₂, which was presumably due to the synergetic effect of the enhanced negative potential and precisely controlled molecular size of the grafted diamine. Based on the excellent peroxidase-like activity of TMBDA-MIL-100(Fe), choline and ACh were reliably determined down to 0.027 and 0.036 µM, respectively. Furthermore, practical applicability of this strategy was successfully demonstrated by detecting choline and ACh in spiked samples of milk and serum, respectively. This work highlights the advantages of amine-grafted MOFs for the preparation of biomimetic catalysts, extending their scope to biosensor applications.

我们在这里描述了新型的胺接枝金属-有机骨架（MOFs）作为天然过氧化物酶的一种有前途的替代品，以及它们在胆碱（Cho）和乙酰胆碱（ACh）的荧光分析中的应用。在各种胺官能化的MOF中，N，N，N '，N'-四甲基-1,4-丁二胺（TMBDA）官能化的MIL-100（Fe）（TMBDA-MIL-100（Fe））表现出最高的过氧化物酶活性通过在H ₂ O ₂存在下从Amplex UltraRed（AUR）产生强烈的荧光，这可能是由于负电势增强和接枝二胺分子大小受到精确控制的协同作用所致。基于TMBDA-MIL-100（Fe）的出色的过氧化物酶样活性，可以可靠地将胆碱和ACh分别测定至0.027和0.036 µM。此外，通过分别检测加标的牛奶和血清样品中的胆碱和乙酰胆碱，成功地证明了该策略的实用性。这项工作突出了胺接枝的MOF在制备仿生催化剂方面的优势，并将其范围扩展到了生物传感器应用领域。