Preparation, characterization and antimicrobial activity evaluation of electrospun PCL nanofiber composites of resveratrol nanocrystals.

The objective of this study was to develop resveratrol nanocrystals to solve low water solubility issues of resveratrol and adsorb them to the polycaprolactone nanofibers. Nanocrystals were prepared by microfluidization. Particle size, polydispersity index and zeta potential values were evaluated as dependent variables. Polycaprolactone (PCL) nanofibers were prepared via electrospinning method and the flow rate, electrical voltage and tip-to-collector distance were set to 3 mL/h, 13 kV and 15 cm, respectively. Optimum resveratrol nanocrystals were lyophilized and re-suspended in water and physically adsorbed to PCL nanofibers with two different concentrations (0.2 and 1 mg/cm2). Bioadhesion, wettability, solubility, drug loading and antimicrobial activity against Propionibacterium acnes studies were carried out. Final nanocrystals showed 800 nm of particle size, 0.4 of polydispersity index, and -8 mV of zeta potential. Nanocrystals successfully adsorbed to PCL nanofibers proven on SEM images with adsorption efficiencies >70%. Adsorption of resveratrol nanocrystals decreased the contact angle of PCL from 128° to 50°. The solubility of resveratrol nanocrystals enhanced ∼5-fold in comparison with coarse powder. Effective antimicrobial activity against P. acnes was observed. It is concluded that nanocrystal loading on nanofibers brings advantage into preparing easy to use dermal patches for acne treatment or skin disorders.