Abstract Biofouling is a critical issue which accounts for >45% of all fouling in reverse osmosis (RO). Because fouling occurs on the surface of the membrane, surface modification has been considered an effective measure for fouling mitigation and for achieving sustainable membrane performance. Herein, we modified a RO membrane using graphene oxide (GO) crosslinked with a thin layer of polydopamine (PDA-GO) to obtain a bactericidal and antibiofouling surface. Optical coherence tomography (OCT) was used as a non-destructive, real-time, in situ monitoring tool to observe the fouling dynamics and to understand material-foulant interaction. In situ three-dimensional (3D) monitoring results showed that the modified membrane was antifouling in nature and exhibited low and fully reversible biofilm formation. In addition, the colony forming unit enumeration and results of confocal laser scanning microscopy reveal that the PDA-GO coated membrane exhibited a high bactericidal effect when compared with pristine, PDA, and GO-coated membrane surfaces. Investigation of bacterial cell morphology further validated that the presence of a GO layer and its functional groups combined with a thin PDA layer resulted in physical and chemical disruption of the bacterial cell wall. The high selectivity of the modified membrane against the monovalent salt validated its potential for desalination and wastewater reclamation.

中文翻译：

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原位光学相干断层扫描评价聚多巴胺交联氧化石墨烯反渗透膜抗菌粘附性能

摘要 生物污垢是一个关键问题，占反渗透 (RO) 中所有污垢的 45% 以上。由于污染发生在膜表面，因此表面改性被认为是减轻污染和实现可持续膜性能的有效措施。在此，我们使用氧化石墨烯 (GO) 与聚多巴胺 (PDA-GO) 薄层交联来改性 RO 膜，以获得杀菌和抗生物污垢表面。光学相干断层扫描 (OCT) 被用作一种非破坏性、实时、原位监测工具，用于观察结垢动态并了解材料与污染物的相互作用。原位三维 (3D) 监测结果表明，改性膜本质上具有防污性，并表现出低且完全可逆的生物膜形成。此外，菌落形成单位计数和共聚焦激光扫描显微镜的结果表明，与原始、PDA 和 GO 涂层膜表面相比，PDA-GO 涂层膜表现出较高的杀菌效果。对细菌细胞形态的研究进一步证实了 GO 层的存在及其官能团与薄 PDA 层的结合导致细菌细胞壁的物理和化学破坏。改性膜对一价盐的高选择性验证了其在海水淡化和废水回收方面的潜力。对细菌细胞形态的研究进一步证实，GO 层的存在及其官能团与薄的 PDA 层相结合，导致细菌细胞壁的物理和化学破坏。改性膜对一价盐的高选择性验证了其在海水淡化和废水回收方面的潜力。对细菌细胞形态的研究进一步证实了 GO 层的存在及其官能团与薄 PDA 层的结合导致细菌细胞壁的物理和化学破坏。改性膜对一价盐的高选择性验证了其在海水淡化和废水回收方面的潜力。