Surface Modification of Membrane Filters Using Graphene and Graphene Oxide-Based Nanomaterials for Bacterial Inactivation and Removal

Abstract

Surfaces of commercially available membrane filters were modified by the dispersion of poly(N-vinylcarbazole) (PVK), graphene (G), poly(N-vinylcarbazole)-graphene (PVK-G), graphene oxide (GO), and poly(Nvinylcarbazole)-graphene oxide (PVK-GO) in order to impart antibacterial properties. The successful coatings of the membranes were demonstrated through scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Investigations carried out on the surface-modified membrane filters using Escherichia coli and Bacillus subtilis showed that the presence of graphene-based nanomaterials significantly improved the antibacterial properties of the membrane filters. One of the mechanisms for this improved antimicrobial property of the filter was attributed to the production of reactive oxygen species by the nanomaterials. Among the nanomaterials used in this study, the PVK-GO-modified membrane filter exhibited the best removal of B. subtilis and E. coli with 4 and 3 log removals, respectively. The different levels of E. coli and B. subtilis removals were attributed to the differences in their cell structures and composition. This study has demonstrated that the use of graphene-based nanomaterials to modify the surfaces of membrane filters is an effective method of imparting antibacterial properties that can find useful application in water and wastewater treatment.

Graphene oxide: the new membrane material

“…2(C) is the schematic for possible water vapor transport method through GO membrane. Nair et al [1] explains that the GO laminates are made of crystallites stacked on top of each other and the hydroxyl and epoxy groups attached to the graphene sheets offers spacing between the Water transport [50] Ozonated graphene oxide membrane Proton exchange [54] Graphene oxide membrane filters Bacterial inactivation and removal [56] Graphene oxide membrane Desalination [60] membranes. According to their model and explanation, the pristine graphene capillaries are wide open to accommodate the water molecule and the capillaries becomes narrow in low humidity, which do not provide enough Vander-Waals distance to accommodate water molecules and this mechanism is shown in the Fig.…”

“…Such type of scalable GO membranes has futuristic applications in regenerative medicine. In another work, Rodrigues et al [56] has reported the usefulness of graphene oxide modified membranes for the removal of bacteria and their inactivation. The reported superior antibacterial activity of these modified membranes was due to the production of reactive oxygen species (ROS) which is capable of damaging the bacterial cell and hinders their metabolic activity which in turn inhibit the bacterial growth.…”

Engineered nanomaterials for water treatment and remediation: Costs, benefits, and applicability

“…Contamination of surface waters also constitutes a risk to water supplies because pollutants may penetrate into aquifers, where they can be transported to drinking water sources. These challenges, among others, bring into focus the need for alternative water treatment and pollutant remediation methods to complement [7] or replace existing technologies.…”

“…The use of engineered nanomaterials (ENMs) for water treatment is currently limited to exploring their potential to act as effective adsorbents [8], filters [9], disinfectants [7,10,11], and reactive agents [12,13], although they show promise for full scale water treatment and environmental remediation [14][15][16]. However, relatively little progress has been made compared to the application of nanotechnology in fields such as medicine and electronics.…”

Obtenção de microesferas quitosana/taninos extraídos da casca de <i>Eucalyptus urograndis</i> para utilização piloto na tratabilidade físico-química de água bruta com turbidez entre 100-110 NTU

“…Portanto, o aumento de alternativas para o tratamento de água e remediação de poluentes se torna desafio para a complementação ou substituição das tecnologias existentes (QU et al, 2012;MUSICO et al, 2014).…”