Acrylic Bone Cements Modified with Graphene Oxide: Mechanical, Physical, and Antibacterial Properties

Abstract

Bacterial infections are a common complication after total joint replacements (TJRs), the treatment of which is usually based on the application of antibiotic-loaded cements; however, owing to the increase in antibiotic-resistant microorganisms, the possibility of studying new antibacterial agents in acrylic bone cements (ABCs) is open. In this study, the antibacterial effect of formulations of ABCs loaded with graphene oxide (GO) between 0 and 0.5 wt.% was evaluated against Gram-positive bacteria: Bacillus cereus and Staphylococcus aureus, and Gram-negative ones: Salmonella enterica and Escherichia coli. It was found that the effect of GO was dependent on the concentration and type of bacteria: GO loadings ≥0.2 wt.% presented total inhibition of Gram-negative bacteria, while GO loadings ≥0.3 wt.% was necessary to achieve the same effect with Gram-positives bacteria. Additionally, the evaluation of some physical and mechanical properties showed that the presence of GO in cement formulations increased wettability by 17%, reduced maximum temperature during polymerization by 19%, increased setting time by 40%, and increased compressive and flexural mechanical properties by up to 17%, all of which are desirable behaviors in ABCs. The formulation of ABC loading with 0.3 wt.% GO showed great potential for use as a bone cement with antibacterial properties.

The Role of Chitosan and Graphene Oxide in Bioactive and Antibacterial Properties of Acrylic Bone Cements

“…On the other hand, according to the results presented by Paz et al [114], ABCs modified with 0.1 wt.% of GO showed a lack of antimicrobial activity against S. Aureus, possibly because the GO powder level was below the threshold required for a positive antimicrobial response. This confirms the results obtained by several authors, who affirmed that GO's antibacterial activity depends on the concentration [108,163,164]. Table 4 shows a summary of the strategies used to confer antimicrobial activity to bone cements and the characteristics offered by CS and GO.…”

“…The addition of GO in percentages up to 0.5 wt.% in ABCs has favored bending and compression [107][108][109][110]. Paz et al [110] reported increased fracture toughness and fatigue performance attributed to the GO, induced deviations in the crack fronts, and hampered crack propagation.…”

“…Several authors reported that the increase in GO content in ABCs decreases the maximum polymerization temperature. It acts as an inhibitory and retardant agent of the MMA polymerization reaction [107,108,110], which decreases the risk of thermal necrosis and improves the cement's bioactivity. On the other hand, this inhibitory effect on the polymerization reaction has generated an increase in the cement's residual monomer content, which increases the possibility of chemical necrosis of the surrounding tissue with percentages of GO higher than 0.3 wt.% [108].…”

“…When evaluating the antibacterial activity of cements added with GO against Gram-positive bacteria Bacillus cereus and S. aureus and Gram-negative Salmonella enterica and E. coli, it was found that the increase in GO content up to 0.5 wt.% increased this property significantly in the cement with both types of bacteria with a level of significantly lower than 0.01 [108]. Likewise, in other investigations, it has been confirmed the antibacterial activity of bone cements against E. coli, with GO percentages of 0.3 wt.% [101,109].…”

Porous Graphene Composite Polymer Fibres

“…Irrespective of the PG loading shown in ( Table 1 ), in some instances, the pores penetrate deep into the fibre [ 47 ]. The surface pores are therefore beneficial in exposing the PG layers to the environment, which is useful in antimicrobial applications [ 55 , 56 ].…”