Enhanced antibacterial activity of a novel biocompatible triarylmethane based ionic liquid-graphene oxide nanocomposite

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2021-07, Vol.203, p.111729-111729, Article 111729
• Main Authors: Prusty, Susmita, Pal, Kunal, Bera, Debbethi, Paul, Anindita, Mukherjee, Madhubroto, Khan, Finaz, Dey, Anindita, Das, Susmita
• Format: Article
• Language: English
• Subjects: Antibacterial coatings; Graphene oxide; Ionic liquid; Nanocomposites
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2021.111729

[Display omitted] •A novel GO-nanocomposite with newly designed Triarylmethane based antibacterial Ionic Liquids synthesized.•Bactericidal effect of nanocomposite in contrast to bacteriostatic effect of GO is observed.•Prolonged resistance to bacterial growth on the nanocomposite coated films.•Potential antibacterial coating materials for biomedical surfaces. Biofilm formation on medical implants and devices has been a severe concern that results in their impaired performance and life-threatening complications. Thus, development of novel functional coatings for infection prone surfaces with biofilm inhibiting characteristics is of prime significance considering the rapid emergence of multidrug resistant bacteria. Herein we present a novel nanocomposite derived from Graphene Oxide (GO) and a newly developed functional Ionic liquid (IL) obtained through a metathesis reaction between a triarylmethane dye hexamethyl pararosaniline chloride or crystal violet (CV) and sodium dodeceyl sulfate (SDS) to yield [CV][DS] (hexamethyl pararosaniline dodecyl sulfate). This highly biocompatible [CV][DS]-GO nanocomposite exhibit more than four times improved antibacterial activity in comparison to bare GO against both gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus). As suggested by XRD, FTIR and UV absorption and SEM results improved activity of [CV][DS]-GO nanocomposite is ascribed to the synergistic effect of reduced nanocomposite sheet thickness, enhanced amphiphilicity imparted by dodecylsulfate (DS), exposed active ArN+ groups of CV and some inherent functionalities of GO. This is also complemented by the ruptured and diffused S. aureus cell walls as observed in bacterial SEM result. In contrast, the nanocomposites of the precursors with GO do not demonstrate any significant antibacterial effect. Coatings developed using GO upon infestation with E. coli revealed significant biofilm formation after 48 and 72 h of incubation while [CV][DS]-GO coated surface demonstrated no colony growth under similar circumstances. Thus, [CV][DS]-GO nanocomposite coatings exhibit excellent resistance to bacterial growth even up to 72 h incubation signifying its bactericidal effect. Therefore, the developed nanocomposite may be considered as one of the improved antibacterial wash resistant coating material for biomedical devices and surfaces susceptible to to biofilm formation.