Photodynamic antibacterial application of TiO2/curcumin/ hydroxypropyl-cyclodextrin and its konjac glucomannan composite films

Although photodynamic therapy (PDT) has great advantages for the treatment of bacterial infections, photo-sensitizers (PSs) often have many disadvantages that limit their application. Improving the shortcomings of PSs and developing efficient PDT antimicrobial materials remain serious challenges. In this study, a nanocomposite drug (TiO2/curcumin/hydroxypropyl-cyclodextrin, TiO2/Cur/HPCD) was constructed and combined with konjac glucomannan to form composite films (TiO2/Cur/HPCD films, KTCHD films). The stabilities of TiO2 and Cur were improved in the presence of HPCD. The particle size of TiO2/Cur/HPCD was approximately 33.9 nm, and the addition of TiO2/Cur/HPCD enhanced the mechanical properties of the films. Furthermore, TiO2/Cur/HPCD and KTCHD films exhibited good biocompatibility and PDT antibacterial effects. The antibacterial rate of TiO2/Cur/ HPCD was 74.46 % against MRSA at 500 mu g/mL and 99.998 % against E. coli at 400 mu g/mL, while it was adsorbed on the surface of bacteria to improve the effectiveness of the treatment. In addition, studies in mice confirmed that TiO2/Cur/HPCD and KTCHD films can treat bacterial infections and promote wound healing, with a highest wound healing rate of 84.6 % in the KTCHD-10 films + Light group on day 12. Overall, TiO2/Cur/HPCD is a promising nano-antibacterial agent and KTCHD films have the potential to be employed as antibacterial and environment-friendly trauma dressings.