Three-dimensional macro/micro-porous curcumin releasing polycaprolactone/chitosan nanofiber scaffolds as wound dressing

Abstract

In this study, three-dimensional (3D) polycaprolactone (PCL)-chitosan (Chi)-curcumin (Cur) nanofibrous wound dressings were fabricated with a dispersion shaping method. After conventional electrospinning of PCL-Chi and PCL-Chi-Cur mixture, bead-free and smooth nanofibers with the mean diameters between 90 – 160 nm were successfully obtained. Then, 3D nanofibrous PCL-Chi and PCL-Chi-Cur wound dressings with mean diameters of 235 ± 50 nm and 226 ± 47 nm, respectively, were fabricated in macro/micro-porous structure. According to the micro-computerized tomography analysis, 3D nanofibrous PCL-Chi and PCL-Chi-Cur materials had the mean pore sizes of 97 µm and 208 µm with the total porosity of 90%. When chitosan was added to the structure, the hydrophilicity and water uptake capacity of the developed materials were significantly improved. Furthermore, curcumin was successfully loaded into 3D nanofibrous structures with 61% encapsulation efficiency and 3% drug loading capacity. When the curcumin release was analysed, it was observed that 55% of the loaded curcumin was released within the first 3 h, and the release was completed at the end of 10 h with the released amount of 64%. Kinetic analyzes revealed that the release profile was diffusion controlled in accordance with the Higuchi model. Cell culture studies were performed with human dermal fibroblasts (HDFs) and cell metabolic activity and morphology were monitored by MTT and SEM analyses, respectively. The presence of curcumin in 3D nanofibrous wound dressings had a positive effect on the viability and proliferation of HDF cells, albeit decreasing, especially in the first 7 days of culture, but this effect almost disappeared on day 14. In SEM analyses, it was observed that HDFs in all groups migrated to the depths of the material through macropores, but it can be said that cell-cell and cell-matrix interactions were much better in the PCL-Chi-Cur group. Hence, curcumin-incorporated 3D nanofibrous material containing macro/micro pores within the structure have potential to be a good alternative wound dressing in the future when curcumin release is further extended.