ACS Appl Mater Interfaces. 2018 May 2;10(17):15189-15199. doi: 10.1021/acsami.7b19455. Epub 2018 Apr 20.
In the present study, a new copper metal-organic framework (MOF)-cotton material was strategically fabricated to exploit its antibacterial properties for postsynthetic modification (PSM) to introduce a free amine to tune the physicochemical properties of the material. A modified methodology for carboxymethylation of natural cotton was utilized to enhance the number of nucleation sites for the MOF growth. Subsequently, MOF Cu(NHBTC) was synthesized into a homogenous surface-supported film via a layer-by-layer dip-coating process. The resultant materials contained uniformly distributed 1 μm × 1 μm octahedral MOF crystals around each carboxymethylated fiber. Importantly, the accessible free amine of the MOF ligand allowed for the PSM of the MOF-cotton surface with valeric anhydride, yielding 23.5 ± 2.2% modified. The Cu ion-releasing performance of the materials was probed under biological conditions per submersion in complex media at 37 °C. Indeed, PSM induces a change in the copper flux of the material over the first 6 h. The materials continue to slowly release Cu ions beyond 24 h tested at a flux of 0.22 ± 0.003 μmol·cm·h with the unmodified MOF-cotton and at 0.25 ± 0.004 μmol·cm·h with the modified MOF-cotton. The antibacterial activity of the material was explored using Escherichia coli by testing the planktonic and attached bacteria under a variety of conditions. MOF-cotton materials elicit antibacterial effects, yielding a 4-log reduction or greater, after 24 h of exposure. Additionally, the MOF-cotton materials inhibit the attachment of bacteria, under both dry and wet conditions. A material of this type would be ideal for clothing, bandages, and other textile applications. As such, this work serves as a precedence toward developing uniform, tunable MOF-composite textile materials that can kill bacteria and prevent the attachment of bacteria to the surface.
在本研究中，我们策略性地制备了一种新的铜基金属-有机骨架（MOF）-棉材料，以利用其抗菌性能进行后合成修饰（PSM），引入游离胺来调节材料的物理化学性质。我们利用一种改良的天然棉羧甲基化方法来增加 MOF 生长的成核位点数量。随后，通过层层浸涂工艺将 MOF Cu(NHBTC)合成到均匀的表面支撑薄膜中。所得材料在每个羧甲基化纤维周围包含均匀分布的 1 μm×1 μm 八面体 MOF 晶体。重要的是，MOF 配体的游离胺可用于 MOF-棉表面的 PSM，用戊酸酐进行修饰，得到 23.5±2.2%的改性。在 37°C 的复杂介质中浸泡测试材料的铜离子释放性能。事实上，PSM 会在最初 6 小时内改变材料的铜通量。在未修饰的 MOF-棉和修饰的 MOF-棉中，铜通量分别为 0.22±0.003 μmol·cm·h 和 0.25±0.004 μmol·cm·h，在超过 24 小时的测试中，材料仍会持续缓慢释放铜离子。通过测试各种条件下的浮游菌和附着菌，研究了材料的抗菌活性。MOF-棉材料在暴露 24 小时后表现出抗菌作用，可使细菌减少 4 个对数级或更多。此外，MOF-棉材料在干燥和湿润条件下均能抑制细菌的附着。这种类型的材料非常适合用于服装、绷带和其他纺织品应用。因此，这项工作为开发能够杀死细菌并防止细菌附着在表面的均匀、可调谐的 MOF-复合纺织品材料奠定了基础。
