Antibacterial resorbable barrier membranes with therapeutic activity for guided tissue regeneration

The objective of this study was to develop a bioabsorbable membrane composed of poly(butylene adipate-co-terephthalate) (PBAT) with alkyl trimethyl ammonium bromide (ATAB) to provide antimicrobial properties. Membranes were manufactured via the solvent casting technique using chloroform solutions containing PBAT and varying concentrations of ATAB (1, 2.5, and 5% wt), with ATAB-free membranes as a control. The characterization of the membranes included assessments of contact angle, surface free energy, and degradation in distilled water over periods of one week, one month, and three months. Mechanical properties were evaluated via tensile strength, and changes in water pH were monitored from 24 hours to three months post-immersion. Cytotoxicity was assessed using gingival fibroblasts and pre-osteoblasts via the SRB assay. Antimicrobial activity was tested against Staphylococcus aureus. ATAB inclusion reduced water contact angle and increased surface free energy compared to controls (p < 0.001). The addition of 5% wt ATAB decreased the tensile strength of PBAT membranes. At one month, a reduced mass was observed for the 2.5% wt ATAB membrane. The specimens' mass was reduced for all groups after three months of immersion in water in comparison to the initial measurement, while a reduction in thickness was found in all time points, without the influence of ATAB. ATAB incorporation reduced cell viability. Antimicrobial efficacy, resulting in a > 3 log10 bacterial reduction, was observed for S. aureus at the 5% wt concentration. The addition of 2.5% wt ATAB to PBAT membranes may be a suitable strategy to generate barrier membranes with an antibacterial effect while maintaining acceptable mechanical and surface properties.