Centro de Nanotecnologia e Materiais Técnicos, Funcionais e Inteligentes (CeNTI) , 4760-034 Vila Nova de Famalicão, Portugal.
2C2T-Centro de Ciência e Tecnologia Têxtil, Universidade do Minho, Campus de Azurém , 4800-058 Guimarães, Portugal.
ACS Appl Mater Interfaces. 2017 Sep 27;9(38):33107-33118. doi: 10.1021/acsami.7b09068. Epub 2017 Sep 12.
Two different nanofibrous antibacterial membranes containing enzymatically synthesized poly(catechol) (PC) or silver nitrate (AgNO, positive control) blended with poly(vinyl alcohol) (PVA) and electrospun onto a poly(vinylidene fluoride) (PVDF) basal disc to generate thin-film composite midlayers were produced for water ultrafiltration applications. The developed membranes were thoroughly characterized in terms of morphology, chemical composition, and general mechanical and thermal features, antimicrobial activity, and ultrafiltration capabilities. The electrospun blends were recognized as homogeneous. Data revealed relevant conformational changes in the PVA side groups, attributed to hydrogen bonding, high thermal stability, and residual mass. PVDF+PVA/AgNO membrane displayed 100% growth inhibition of both Gram-positive and Gram-negative bacteria strains, despite the wide range of fiber diameters generated, from 24 to 125 nm, formation of numerous beads, and irregular morphology. The PVDF+PVA/PC membrane showed a good growth inhibition of Staphylococcus aureus (92%) and revealed a smooth morphology with no relevant bead formations and diameters ranging from 68 to 131 nm. The ultrafiltration abilities of the membrane containing PVA/PC were tested in a dead-end high-pressure cell (4 bar) using a reactive dye in distilled water and seawater. After 5 cycles, a maximum rejection of ≈85% with an average flux rate of 70 L m h for distilled water and ≈64% with an average flux rate of 62 L m h for seawater were determined with an overall salt rejection of ≈5%.
两种不同的纳米纤维抗菌膜，分别含有酶合成的聚（儿茶酚）（PC）或硝酸银（AgNO，阳性对照），与聚乙烯醇（PVA）混合，并通过静电纺丝到聚偏二氟乙烯（PVDF）基底盘上，生成薄膜复合中层，用于水超滤应用。所开发的膜在形态、化学组成、一般机械和热特性、抗菌活性和超滤性能方面进行了全面的表征。电纺混合物被认为是均匀的。数据显示 PVA 侧基发生了相关的构象变化，归因于氢键、高热稳定性和残留质量。尽管生成的纤维直径范围从 24 到 125nm 不等，形成了许多珠粒，并且形态不规则，但 PVDF+PVA/AgNO 膜对革兰氏阳性和革兰氏阴性细菌菌株的生长抑制率达到 100%。PVDF+PVA/PC 膜对金黄色葡萄球菌有很好的生长抑制作用（92%），呈现出光滑的形态，没有相关的珠粒形成，直径范围从 68 到 131nm。在死端高压池（4 巴）中，使用活性染料在蒸馏水中和海水中测试了含有 PVA/PC 的膜的超滤能力。经过 5 个循环，在蒸馏水中的最大截留率约为 85%，平均通量为 70L m h，在海水中的最大截留率约为 64%，平均通量为 62L m h，总盐截留率约为 5%。
