载酶纳米催化体系用于疾病诊疗的研究进展

酶作为一种具有高度特异性和高效性的催化剂, 可在细胞器中通过复杂有序的生化反应调节细胞的代谢过程. 受细胞区隔化结构的启发, 仿生设计纳米酶催化体系、 构筑限域酶催化微环境从而提高酶催化活性的研究为酶催化应用开辟了新思路. 纳米催化体系保留了小尺寸、 大比表面积、 肿瘤部位选择性富集等优势, 在疾病的诊疗方面发挥了巨大的优势. 本文首先总结了天然酶、 模拟酶和级联酶体系的催化机理, 对仿生构筑的纳米酶催化材料的载体体系进行了概述, 介绍了纳米酶催化体系在生物成像方面的应用, 讨论了其在相关代谢类疾病的作用途径, 并对纳米酶催化体系用于生物诊疗的发展前景进行了展望.     

Removal of methylene blue with hemicellulose/clay hybrid hydrogels

In this study, we chose corn stover hemicellulose for the preparation of hydrogels with admirable adsorption properties under mild alkaline conditions. Clay nanosheets were introduced to this system and hemicellulose/clay hybrid hydrogels were prepared. Morphological, mechanical properties and the methylene blue adsorption behaviors of the prepared hydrogels were studied. Results suggested that the addition of clay not only improved the mechanical strength of hemicellulose-based hydrogels, but also increased the adsorption capacity on methylene blue. Moreover, the adsorptions were confirmed to follow pseudo-second order equation for both gels with and without clay. The maximum adsorption capacities on methylene blue for hemicellulose-based hydrogels with or without clay reached 148.8 and 95.6 mg/g, respectively. These results implied that hemicellulose-based hydrogels could be used as promising adsorbents for the removal of methylene blue from waste water.