Photothermally Active Reduced Graphene Oxide/Bacterial Nanocellulose Composites as Biofouling-Resistant Ultrafiltration Membranes

Abstract

Biofouling poses one of the most serious challenges to membrane technologies by severely decreasing water flux and driving up operational costs. Here, we introduce a novel anti-biofouling ultrafiltration membrane based on reduced graphene oxide (RGO) and bacterial nanocellulose (BNC), which incoporates GO flakes into BNC in situ during its growth. In contrast to previously reported GO-based membranes for water treatment, the RGO/BNC membrane exhibited excellent aqueous stability under environmentally relevant pH conditions, vigorous mechanical agitation/sonication, and even high pressure. Importantly, due to its excellent photothermal property, under light illumination, the membrane exhibited effective bactericidal activity, obviating the need for any treatment of the feedwater or external energy. The novel design and in situ incorporation of the membranes developed in this study present a proof-of-concept for realizing new, highly efficient, and environmental-friendly anti-biofouling membranes for water purification.

Effect of biosurfactant derived from Vibrio natriegens MK3 against Vibrio harveyi biofilm and virulence

“…EPS secretion may be a defensive reaction of marine pathogens to environmental stresses, which is a crucial feature of biofilm development. EPS offers binding sites for pathogens, and ultimately, the amassed EPS layer entangles pathogenic biomass, making the bacteria tougher to antibacterial substances . Hence, we measured that inhibiting EPS secretion would be a prudent approach to constrain biofilm development, which would make the pathogen become much more sensitive upon treatment.…”

Applications of Nanocellulose/Nanocarbon Composites: Focus on Biotechnology and Medicine

“…These composites can be created by filtration [127], filtration combined with hot pressing for fabricating films [128], or by freeze-drying [75] and freeze-casting [48] for fabricating 3D materials, such as aerogels and foams. Other methods are deposition of graphene on a nanocellulose layer [43] and incorporation of graphene into nanocellulose during its biological synthesis by bacteria [54][55][56].…”

“…In order to modulate the properties of nanocellulose/graphene composites for specific applications, these materials can be further enriched by various substances, such as metallic or ceramic nanoparticles, oxides, carbides, sulfides, vitamin C, synthetic and natural polymers, enzymes and antibodies. For example, nanocellulose/graphene composites have high adsorption, filtration and photocatalytic ability, and they are therefore widely used for water purification, e.g., for removing antibiotics [75], dyes [43], heavy metals, such as Cu 2+ , Hg 2+ , Ni 2+ and Ag + [61,76], or for their bactericidal effect [56]. The water-cleaning capacity of these composites can be further enhanced by introducing additional photocatalytic agents, i.e., palladium nanoparticles [54] or zinc oxide (ZnO) nanoparticles [73].…”

“…Integration of nanocarbon materials with nanocellulose provides functionality of nanocarbons, using an eco-friendly, low-cost, strong, dimension-stable, nonmelting, nontoxic and nonmetal matrix or carrier, which alone has versatile applications in industry, biotechnology and biomedicine (for a review, see [1,2]). In addition to its advantageous combination with nanocarbon materials, nanocellulose is an appealing material for biomedical applications due to its tunable chemical fluorescence and luminescence [26,71,72] photothermal activity [56], hydrolytic stability [61], nanoporous character and high adsorption capacity [49,61]. Nanocellulose/nanocarbon composites can therefore be used in a wide range of industrial and technological applications, such as water purification [22,29,43,49,54,56,61,[73][74][75][76], the isolation and separation of various molecules [22,74,[77][78][79], energy generation, storage and conversion [21,23,44,47,64,[80][81][82][83][84][85], biocatalysis [86], food packaging [67][68][69]87], construction of fire retardants …”

Biofabrication of multifunctional nanocellulosic 3D structures: a facile and customizable route

“…The natural hydrophilicity of cellulose nanomaterials makes them ideal for combining with hydrophilic polymers but chemical modifications can be used to facilitate incorporation with hydrophobic polymers (Siró and Plackett, 2010). In addition to combinations with polymers such as poly(lactic acid) and poly(vinyl alcohol), nanocelluloses have been compounded with various other materials, including clays (Liu et al, 2011;Wu et al, 2012;Hokkanen et al, 2018) and graphene oxide (Jiang et al, 2019;Xing et al, 2019). Besides improving mechanical properties, nanocelluloses can enhance thermal and barrier properties of the produced composites.…”