School of Environmental and Chemical Engineering, Xi'an Laboratory of Textile Chemical Engineering Auxiliaries, Xi'an Polytechnic University, Xi'an 710048, PR China.
School of Chemistry and Chemical Engineering, The Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University, Shihezi 832003, PR China.
Langmuir. 2023 Jun 20;39(24):8404-8413. doi: 10.1021/acs.langmuir.3c00362. Epub 2023 Jun 7.
In this work, the strategy of immobilizing enzymes in bimetallic-organic frameworks was adopted to overcome the disadvantages of free laccases. The surface amino-silanizing of bimetallic CoCu-MOF-H hydrothermally synthesized was performed by (3-Aminopropyl)triethoxysilane (APTES). Then, glutaraldehyde was used as the cross-linking agent, laccase was covalently grafted onto CoCu-MOF-H-APTES to prepare Lac-CoCu-MOF-H-APTE. In addition, CoCu-MOF-OH also was synthesized by alkali etching of CoCu-MOF-H, and Lac-CoCu-MOF-OH-APTES composites were obtained by a similar strategy. The result showed that the relative enzyme activity of Lac-CoCu-MOF-OH-APTES exhibited 264.02% (1.8 times than that of Lac-CoCu-MOF-H-APTES) after six cycles of stability tests, while the free enzyme was almost inactivated. Moreover, the Congo red (CR) removal rate of Lac-CoCu-MOF-OH-APTES exceeded 95% within 1 h and exceeded 89.18% after six cycles at pH 3.5 and 50 °C. This work has the potential to provide a broader application prospect for CR degradation by laccase in the future.
在这项工作中，采用了将酶固定在双金属有机骨架中的策略来克服游离漆酶的缺点。通过（3-氨丙基）三乙氧基硅烷（APTES）对水热合成的双金属 CoCu-MOF-H 进行表面氨基硅烷化。然后，戊二醛用作交联剂，将漆酶共价接枝到 CoCu-MOF-H-APTES 上，制备 Lac-CoCu-MOF-H-APTE。此外，还通过碱刻蚀 CoCu-MOF-H 合成了 CoCu-MOF-OH，并通过类似的策略获得了 Lac-CoCu-MOF-OH-APTES 复合材料。结果表明，在经过六次稳定性测试后，Lac-CoCu-MOF-OH-APTES 的相对酶活性表现出 264.02%（比 Lac-CoCu-MOF-H-APTES 高 1.8 倍），而游离酶几乎失活。此外，Lac-CoCu-MOF-OH-APTES 在 1 h 内对刚果红（CR）的去除率超过 95%，在 pH 3.5 和 50°C 下经过六次循环后仍超过 89.18%。这项工作为未来漆酶降解 CR 提供了更广阔的应用前景。
