PLA/PCL polymer nanocomposite with silver and copper nanoparticles and lavender essential oil: Synthesis, characterization and application in tissue engineering

The present work aims to synthesize, characterize, and evaluate the cytotoxicity and antimicrobial activity of PLA/PCL polymeric nanocomposite with silver nanoparticles (AgNPs) and copper (CuNPs) and the addition of lavender essential oil (LEO) for application in tissue engineering. For the synthesis of the nanocomposite films, the central composite rotational design (CCRD 2²) was used, where the ideal condition was 0 .5 %wt. of AgNPs and CuNPs (3:1D) with a higher cell viability (196.1 %) after 24 h. After defining the ideal condition, the effect of incorporating LEO into the polymer blend and nanoparticles in the proportions of 0.5 (3:1D0.5), 0.75 (3:1D0.75) and 1 v^-1 (3:1D1) was evaluated. All nanocomposite films were characterized structurally, morphologically, thermally, and mechanically by X-ray diffraction (XRD), Field Emission Gun–Scanning Electron Microscopy (FEG-SEM), Thermogravimetric analysis (TGA), contact angle and mechanical Properties (displacement and maximum tension). To evaluate cytotoxicity, an in vitro safety profile was performed in HFF-1 (fibroblasts) and HaCat (keratinocytes) cell lines, where PLA/PCL polymer blend with 0.5 %wt. of AgNPs and CuNPs (3:1D) and PLA/PCL polymer blend with 0.5 %wt. of AgNPs and CuNPs and LEO (0.5 v^-1) (3:1D0.5) nanocomposite film showed the best cell viability without the nitric oxide (NO) generation, total levels of reactive oxygen species (ROS) or dsDNA release for the HFF-1 and HaCat cell lines, as well as genoprotective characteristic and without genotoxic profile. Moreover, the tests were carried out on the pH of injured skin at different immersion times (3, 6, 12 and 24 h) and didn´t show cell death or inflammatory reaction. For the antimicrobial activity, the 3:1D, 3:1D0.5, and PLA/PCL polymer blend with 0.5 %wt. of AgNPs and CuNPs and LEO (0.75 v^-1) (3:1D0.75) nanocomposite films showed the formation of biofilm for S. aureus, E. coli, P. aeruginosa and K. pneumoniae. Therefore, the PLA/PCL polymer nanocomposite with AgNPs and CuNPs showed potential application as a healing dressing for skin regeneration.