Trimethoprim Combined With Vancomycin and Gentamicin Composite Bone Cement In Vitro

This study aimed to explore the effect of trimethoprim on the antibacterial efficacy and cell viability of vancomycin- and gentamicin-containing bone cement, aiming to establish a basis for its clinical application. Bone cement was grouped by antibiotic combinations: vancomycin with trimethoprim (groups I-III), gentamicin with trimethoprim (groups IV-VI), vancomycin alone (group VII), gentamicin alone (group VIII), and trimethoprim alone (group IX). Antibacterial efficacy against Staphylococcus aureus (n = 5) was assessed using the plate diffusion method, and cell viability was evaluated using CCK8 assays for cytotoxicity and proliferation (n = 5). Increasing trimethoprim content significantly enhanced antibacterial zones for vancomycin- and gentamicin-based groups ( p < 0.05). Vancomycin-trimethoprim groups showed moderate cytotoxicity by day 5, while other groups demonstrated robust cell proliferation with minimal cytotoxicity ( p < 0.05). Trimethoprim improves the antibacterial efficacy of vancomycin and gentamicin bone cement while maintaining cell viability.