Modeling the impact of fluid flow on resveratrol release from electrospun fibers

Using electrospun fibers to deliver therapeutic agents has gained significant attention in various applications including cancer treatment and tissue regeneration. However, the effect of fluid flow and uptake by cells on the concentration profile is not well understood. In this study, we evaluated the release of lipophilic resveratrol from poly(c-caprolactone) (PCL)-gelatin (GT) electrospun fibers experimentally and by using computational fluid dynamics (CFD). Resveratrol containing PCL-GT electrospun fibers were formed and used in a custom-built tubular bioreactor, to assess flow effect on concentration profile over 5 days. CFD model was developed to simulate release in both static cultures and under fluid flow conditions. Resveratrol stability in the culture medium and uptake by human umbilical vein endothelial cells and K562 cells over 3 days were used in the model. The concentration profile as a function of time was simulated and validated by experiments. The effects of inlet velocity, cellular uptake rate, bioreactor's length, and surrounding tissue porosity were assessed. The release profile was mainly affected by cellular uptake and the presence of porous media. The model suggests that the perfusion velocity might not have a significant effect relative to the cellular uptake rate and porosity of the surrounding tissue.