Utilization of supercritical carbon dioxide in fabrication of cellulose acetate films with anti-biofilm effects against Pseudomonas aeruginosa and Staphylococcus aureus

•Cellulose acetate films were impregnated with thymol using supercritical CO2.•Target thymol contents for desired antibacterial activity were in the range 26–30%.•Thymol prevented S. aureus and P. aeruginosa attachment to films’ surfaces.•Released thymol reduced biofilm formation on the surrounding surfaces.•The films showed strong anti-biofilm activity against antibiotic resistant strains.