Two-dimensional (2D) nanomaterials are attractive in catalysis due to their rich accessible active sites. Iron-based metal organic frameworks (MOFs) are promising nanozymes because of their iron center and pore structure. However, it is challenging to obtain iron-based 2D MOF nanozymes due to the coordinated form of iron. Herein, we report a cation substitution strategy to transform an easily obtained Cu(HBTC)(H₂O)₃ (represented as Cu(HBTC)-1, the product of only two carboxylate groups in 1,3,5-benzenetricarboxylic acid (H₃BTC) ligands linked by Cu ions) nanosheet into a 2D Fe-BTC nanosheet, which was characterized by SEM (scanning electron microscopy), AFM (atomic force microscopy), XPS (X-ray photoelectron spectroscopy), FT-IR (Fourier transform infrared spectroscopy), and XRD (X-ray diffraction). The 2D Fe-BTC nanosheet can catalyze TMB (3,3′,5,5′-tetramethylbenzidine) oxidation by H₂O₂, showing its intrinsic peroxidase mimetic characteristic. The catalytic performance of 2D Fe-BTC was superior to those of its template Cu(HBTC)-1 nanosheet and 3D MIL-100(Fe). Their catalytic activities follow the order of 2D Fe-BTC > MIL-100(Fe) > 2D Cu(HBTC)-1. The peroxidase-like activity of 2D Fe-BTC is 77 times that of its template Cu(HBTC)-1, and 2.2 times that of MIL-100(Fe), a well known 3D crystalline form of iron trimesates. The K_m values of 2D Fe-BTC for TMB and H₂O₂ were 0.2610 mM and 0.0334 mM, which were 1.6 and 1.9-fold lower than those of 3D MIL-100(Fe), respectively. The TMB oxidation rate and H₂O₂ reduction rate at unit mass concentration of the catalyst (K_w) for 2D Fe-BTC were 2.7–72.3 and 1.5–37.9 times those for the previously reported 3D MOF nanozymes, respectively. In terms of the excellent peroxidase mimetic characteristic of 2D Fe-BTC, a sensitive and selective colorimetric biosensing platform for hydrogen peroxide and glucose was developed. The linear ranges are 0.04–30 μM and 0.04–20 μM for H₂O₂ and glucose, with a low detection limit of 36 nM and 39 nM, respectively. The assay was satisfactorily applied to glucose determination in biological matrices.

中文翻译：

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二维铁MOF纳米片作为葡萄糖生物传感的高效纳米酶。

二维（2D）纳米材料因其丰富的可利用活性位点而在催化方面具有吸引力。铁基金属有机骨架（MOF）由于其铁中心和孔结构而成为很有前途的纳米酶。但是，由于铁的配位形式，获得铁基二维MOF纳米酶是一项挑战。在本文中，我们报告了一种阳离子取代策略，用于转化易于获得的Cu（HBTC）（H ₂ O）₃（表示为Cu（HBTC）-1，这是1,3,5-苯三甲酸中仅两个羧酸根的产物（高₃BTC）配体通过Cu离子纳米片连接成二维Fe-BTC纳米片，其特征是通过SEM（扫描电子显微镜），AFM（原子力显微镜），XPS（X射线光电子能谱），FT-IR（傅里叶变换）红外光谱）和XRD（X射线衍射）。2D Fe-BTC纳米片可以通过H ₂ O ₂催化TMB（3,3'，5,5'-四甲基联苯胺）氧化，显示出其固有的过氧化物酶模拟特征。2D Fe-BTC的催化性能优于其模板Cu（HBTC）-1纳米片和3D MIL-100（Fe）。它们的催化活性遵循2D Fe-BTC> MIL-100（Fe）> 2D Cu（HBTC）-1的顺序。2D Fe-BTC的过氧化物酶样活性是其模板Cu（HBTC）-1的77倍，是MIL-偏三酸铁的3D结晶形式MIL-100（Fe）的2.2倍。TMB和H ₂ O ₂的2D Fe-BTC的K _m值分别为0.2610 mM和0.0334 mM，分别比3D MIL-100（Fe）低1.6倍和1.9倍。催化剂单位质量浓度下的TMB氧化速率和H ₂ O ₂还原速率（K2D Fe-BTC的_w）分别是先前报道的3D MOF纳米酶的2.7到72.3倍和1.5到37.9倍。根据2D Fe-BTC的出色的过氧化物酶模拟特性，开发了用于过氧化氢和葡萄糖的灵敏且选择性的比色生物传感平台。H ₂ O ₂和葡萄糖的线性范围分别为0.04–30μM和0.04–20μM，检出限较低，分别为36 nM和39 nM。该测定令人满意地应用于生物基质中的葡萄糖测定。