Modification of Polycaprolactone with TiO2 and ZnO Nanoparticles for Biomedical Applications

Polycaprolactone (PCL) is a promising polymer in the medical field and is already being used in the creation of suture materials and tissue engineering. Due to the limited properties of PCL, in many medical tasks it is necessary to modify it, for example, the addition of antimicrobial properties to reduce the risk of infection in tissue repair processes. In this work, the effect of the introduction of nanoparticles of titanium oxide (NPs-TiO2) and zinc (NPs-ZnO) into the polycaprolactone matrix on its antibacterial activity and biocompatibility was studied. The studied concentrations of NPs ranged from 0.001 to 0.5 wt. %, and the final composites were obtained by casting from a solution. An investigation into the antibacterial activity against the Gram-negative bacterium Escherichia coli revealed high efficacy of the PCL/NPs-TiO2 composites, which increased with rising nanoparticle concentration to 27.6% at a nanoparticle content of 0.5 wt. %. PCL/NPs-ZnO composites did not show such activity. The results obtained demonstrate that the key factor determining the biological activity of a composite is not only the nature of the nanoparticles but also their ability to maintain a nanoscale state during the manufacture of the final composite. PCL/NPs-TiO2 composites may be a promising candidate for the creation of antibacterial materials for medical purposes, for absorbable scaffolds or sutures.