RESEARCH SUMMARY
This study developed electrospun poly(vinyl alcohol) nanofiber platforms containing the quaternary ammonium compounds benzyltriethylammonium chloride (BTEAC) and benzyldimethyldodecylammonium chloride (BDMDAC) for localized antimicrobial treatment of periodontal biofilms. Electrospinning conditions were optimized to produce reproducible PVA nanofibers, after which QAC incorporation was evaluated for its effects on morphology, porosity, surface area, wettability, mechanical properties, thermal stability, swelling, degradation, antimicrobial release, biofilm inhibition, and cytocompatibility. Incorporating BTEAC or BDMDAC reduced nanofiber porosity and surface area while increasing wettability and altering thermal behavior. Mechanical testing showed that QAC incorporation modestly reduced Young’s modulus and tensile strength but substantially increased failure strain, producing a more ductile material while retaining sufficient dry-state integrity for handling. Both formulations showed rapid antimicrobial release, with approximately 76.8% of BTEAC and 71.8% of BDMDAC released within 5 minutes and complete release within 15 minutes. Antimicrobial effectiveness depended on QAC chemistry, concentration, bacterial species, and environmental conditions. PVA-BTEAC showed particularly strong activity against E. coli, S. mutans, and P. gingivalis, while PVA-BDMDAC demonstrated strong activity against S. aureus, S. mutans, and P. gingivalis and showed especially promising antibiofilm performance. Most formulations were non-cytotoxic to L929 fibroblasts, although the highest BTEAC dose reduced viability after 24 hours. Overall, the study demonstrates that QAC-loaded electrospun PVA nanofibers can combine useful mechanical handling properties with rapid local antimicrobial delivery and broad-spectrum antibiofilm activity for potential placement within periodontal pockets.
A CellScale UniVert mechanical tester was used to quantify the dry-state tensile properties of electrospun PVA, PVA-BTEAC, and PVA-BDMDAC nanofiber mats. Specimens were cut into 3 cm × 1 cm rectangles, with final testing dimensions of 2 cm × 1 cm, and specimen thickness was measured with an electronic caliper before testing. Tensile tests were performed with a 0.1 N preload followed by extension at a crosshead displacement rate of 10 mm/min, with three measurements conducted for each formulation. The UniVert-generated stress-strain data showed that pure PVA nanofibers had a Young’s modulus of 109.0 ± 11.6 MPa, compared with 107.5 ± 2.0 MPa for PVA-BTEAC and 103.8 ± 8.9 MPa for PVA-BDMDAC. Tensile strength decreased slightly from 4.3 ± 0.2 MPa for PVA to 4.0 ± 0.1 MPa for PVA-BTEAC and 4.1 ± 0.1 MPa for PVA-BDMDAC. In contrast, QAC incorporation substantially increased ductility, with failure strains of 76.0 ± 4.0% for PVA-BTEAC and 51.7 ± 2.1% for PVA-BDMDAC. These UniVert measurements demonstrated that the antimicrobial additives preserved useful tensile strength while producing more flexible nanofiber mats with sufficient integrity for handling in localized oral applications.
