Graphene Oxide Carboxymethylcellulose Nanocomposite for Dressing Materials

Abstract

Sore, infected wounds are a major clinical issue, and there is thus an urgent need for novel biomaterials as multifunctional constituents for dressings. A set of biocomposites was prepared by solvent casting using different concentrations of carboxymethylcellulose (CMC) and exfoliated graphene oxide (Exf-GO) as a filler. Exf-GO was first obtained by the strong oxidation and exfoliation of graphite. The structural, morphological and mechanical properties of the composites (CMCx/Exf-GO) were evaluated, and the obtained composites were homogenous, transparent and brownish in color. The results confirmed that Exf-GO may be homogeneously dispersed in CMC. It was found that the composite has an inhibitory activity against the Gram-positive Staphylococcus aureus, but not against Gram-negative Pseudomonas aeruginosa. At the same time, it does not exhibit any cytotoxic effect on normal fibroblasts.

Real-Time Visualization of Cellulase Activity by Microorganisms on Surface

“…However, it is important to mention that the roughness of the surface will highly depend on the particular setting, specifically the viscosity and modification ratio of CMC used as well as the percentage of CMC dissolved in the solvent. In conditions similar to the ones used here, the same periodic pattern was observed in pure CMC film [ 71 ], although we could not find any data regarding films hydrolyzed by cellulase. We calculated the roughness of the surface and found that the Root Mean Square (RMS) of the pure CMC film is 17.9 nm ( Figure 7 A).…”

“…Using AFM, it was shown that the untreated CMC film had a regular pattern with small periodic holes about 10 nm in size ( Figure 7 A). AFM measurements on pure CMC films have been performed in the past, especially in the context of nanoparticles incorporation [ 71 , 72 ]. However, it is important to mention that the roughness of the surface will highly depend on the particular setting, specifically the viscosity and modification ratio of CMC used as well as the percentage of CMC dissolved in the solvent.…”

Developing a method for real-time visualization of cellulase activity

“…However, it is important to mention that the roughness of the surface will highly depend on the particular setting, specifically the viscosity and modification ratio of CMC used as well as the percentage of CMC dissolved in the solvent. In conditions similar to the ones used here, the same periodic pattern was observed in pure CMC film 70 , though we could not find any data regarding films hydrolyzed by cellulase. On the contrary, the process of cellulose hydrolysis has been studied using AFM 72,73 , showing the directionality of hydrolysis in the contexts of cellulose fibers orientation.…”

“…Using AFM, we could see that the untreated CMC film had a regular pattern with small periodic holes about 10 nm in size ( Figure 7A). AFM measurements on pure CMC films have been performed in the past especially in the context of nano particles incorporation 70,71 . However, it is important to mention that the roughness of the surface will highly depend on the particular setting, specifically the viscosity and modification ratio of CMC used as well as the percentage of CMC dissolved in the solvent.…”

Mononuclear Perfluoroalkyl-Heterocyclic Complexes of Pd(II): Synthesis, Structural Characterization and Antimicrobial Activity

“…It is noteworthy to highlight that Gram-negative bacteria are protected by a thin protective cell wall and an additional layer of lipoproteins and lipopolysaccharides (LPS), while Gram-positive bacteria are characterized by a thick layer of cell wall and are lacking of the additional LPS membrane. An LPS layer makes the Gram-negative strains much more resistant towards both natural and synthetic molecules [ 5 , 28 , 29 , 30 , 31 ], whose entrance into the cells is hampered by the hydrophobic nature of this additional layer. Actually, the infections due to Gram-negative bacteria are more difficult to eradicate [ 3 , 32 ].…”