Huang Zhonghua, Li Mengkun, Li Na, Tang Xinyuan, Ouyang Zhiyu
Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, Nanjing University of Science and Technology, Nanjing 210094, China; School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
J Nanosci Nanotechnol. 2018 Jul 1;18(7):4524-4533. doi: 10.1166/jnn.2018.15351.
Membrane technology is now being widely used in the field of water treatment for its unique advantages. Layer-by-layer (LbL) self-assembly technique is a convenient and versatile method of modified nanofiltration (NF) membranes fabrication, which can be used to control the thickness and the surface properties of membranes by chemical deposition of polyelectrolytes. Herein, a new kind of composite NF membrane with enhanced antibacterial properties was successfully fabricated through LbL self-assembly method, having polyether sulfone (PES) ultrafiltration (UF) membrane as support layer, N-[(2-hydroxy-3-trimethylammonium)propyl] chloride chitosan (HTCC) and polyacrylic acid (PAA) as active layer, and epichlorohydrin (ECH) as crosslinking reagent. Subsequently, nanosilver was finally loaded on the membrane surface by photoreduction technique. Our results revealed that the positively charged four semi-assembled membranes prepared using 5 g/L HTCC aqueous solution, 1 g/L PAA solution (pH = 6-8), and 0.5 g/L NaCl as supporting salt exhibited optimum performance. Atomic force microscopy and contact angle tests showed that the prepared membranes improved the surface roughness and hydrophilicity as compared to those of the polyether sulfone (PES) membranes. The retention test indicated that the (HTCC/PAA)4HTCC membranes exhibited highly-efficient removal of pharmaceuticals and personal care products in the order of Amlodipine > Atenolol > Carbamazepine > Ibuprofen. The X-ray Diffraction results confirmed the presence of nano-silver on the membrane surface. In addition, the prepared membranes exhibited excellent antibacterial activity, especially against gram-negative bacteria.
膜技术因其独特优势目前在水处理领域得到广泛应用。层层（LbL）自组装技术是一种简便且通用的制备改性纳滤（NF）膜的方法，可通过聚电解质的化学沉积来控制膜的厚度和表面性质。在此，通过LbL自组装方法成功制备了一种具有增强抗菌性能的新型复合NF膜，该膜以聚醚砜（PES）超滤（UF）膜为支撑层，N-[(2-羟基-3-三甲基铵)丙基]氯化壳聚糖（HTCC）和聚丙烯酸（PAA）为活性层，环氧氯丙烷（ECH）为交联剂。随后，通过光还原技术最终将纳米银负载在膜表面。我们的结果表明，使用5 g/L HTCC水溶液、1 g/L PAA溶液（pH = 6 - 8）和0.5 g/L NaCl作为支撑盐制备的带正电荷的四层半组装膜表现出最佳性能。原子力显微镜和接触角测试表明，与聚醚砜（PES）膜相比，制备的膜提高了表面粗糙度和亲水性。截留测试表明，(HTCC/PAA)4HTCC膜对药物和个人护理产品具有高效去除能力，去除顺序为氨氯地平>阿替洛尔>卡马西平>布洛芬。X射线衍射结果证实了膜表面存在纳米银。此外，制备的膜表现出优异的抗菌活性，尤其是对革兰氏阴性菌。
