Mansur Alexandra A P, Custódio Dircéia A C, Dorneles Elaine M S, Coura Fernanda M, Carvalho Isadora C, Lage Andrey P, Mansur Herman S
Center of Nanoscience, Nanotechnology, and Innovation - CeNano(2)I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Brazil.
Departamento de Medicina Veterinária, Universidade Federal de Lavras, UFLA, Brazil.
Int J Biol Macromol. 2023 Mar 15;231:123363. doi: 10.1016/j.ijbiomac.2023.123363. Epub 2023 Jan 21.
The contamination and pollution of wastewater with a wide diversity of chemical, microbiological, and hazardous substances is a field of raising environmental concern. In this study, we developed, for the first time, new hybrid multifunctional nanoplexes composed of ZnS semiconductor quantum dots (ZnS QDs) chemically biofunctionalized with epsilon-poly-l-lysine (ɛPL) and coupled with magnetic iron oxide nanoparticles (MION, FeO) stabilized by carboxymethylcellulose (CMC) for the photodegradation (ZnS) of organic molecules and antibacterial activity (ɛPL) with a potential of recovery by an external magnetic field (FeO). These nanosystems, which were synthesized entirely through a green aqueous process, were comprehensively characterized regarding their physicochemical properties combined with spectroscopic and morphological features. The results demonstrated that supramolecular colloidal nanoplexes were formed owing to the strong cationic/anionic electrostatic interactions between the biomacromolecule capping ligands of the two nanoconjugates (i.e., polypeptide in ZnS@ɛPL and polysaccharide in FeO@CMC). Moreover, these nanosystems showed photocatalytic degradation of methylene blue (MB) used as a model dye pollutant in water. Besides MB, methyl orange, congo red, and rhodamine dyes were also tested for selectivity investigation of the photodegradation by the nanoplexes. The antibacterial activity ascribed to the ɛPL biomolecule was confirmed against Gram-positive and Gram-negative bacteria, including drug-resistance field strains. Hence, it is envisioned that these novel green nanoplexes offer a new avenue of alternatives to be employed for reducing organic pollutants and inactivating pathogenic bacteria in water and wastewater treatment, benefiting from easy magnetic recovery.
含有各种各样化学、微生物和有害物质的废水污染问题日益引起环境关注。在本研究中，我们首次开发了新型杂化多功能纳米复合物，其由用ε-聚-L-赖氨酸（ɛPL）进行化学生物功能化的硫化锌半导体量子点（ZnS QDs）组成，并与通过羧甲基纤维素（CMC）稳定的磁性氧化铁纳米颗粒（MION，FeO）偶联，用于有机分子的光降解（ZnS）和抗菌活性（ɛPL），并具有通过外部磁场（FeO）进行回收的潜力。这些完全通过绿色水相过程合成的纳米系统，结合光谱和形态特征对其物理化学性质进行了全面表征。结果表明，由于两种纳米共轭物的生物大分子封端配体（即ZnS@ɛPL中的多肽和FeO@CMC中的多糖）之间强烈的阳离子/阴离子静电相互作用，形成了超分子胶体纳米复合物。此外，这些纳米系统对水中用作模型染料污染物的亚甲基蓝（MB）表现出光催化降解作用。除了MB，还测试了甲基橙、刚果红和罗丹明染料，以研究纳米复合物光降解的选择性。归因于ɛPL生物分子的抗菌活性已针对革兰氏阳性和革兰氏阴性细菌得到证实，包括耐药现场菌株。因此，可以设想，这些新型绿色纳米复合物为减少水和废水处理中的有机污染物以及灭活致病细菌提供了一种新的替代途径，并且受益于易于磁回收。
