Controlled Drug Release from Hydrogel Embedded with Cells

Background: Fibrin hydrogel is an important biological material for tissue engineering and drug delivery applications. As such, fibrin is typically combined with cells and with different biomolecules such as growth factors. Previous studies have analyzed the release profile of different molecules from fibrin gels, however, the effect of gel-embedded cells on the release is not well understood.

Methods: In this study, we explored the controlled release of FITC dextran 250 kDa and 2000 kDa from fibrin hydrogel with and without fibroblast and endothelial cells by fluorescent spectrophotometer.

Results: The results indicate that the addition of cells to fibrin hydrogels decreased the FITC dextran release rate, relatively to acellular gels. At early time points (up to 4 hours from cell seeding) the release profile is slowed down by the physical presence of cells, and at later time points (after 24 hr) the release is enhanced by cells degrading the gels.

Conclusions: Cells-applied forces and matrix deformation were not found to significantly influence the release profile. This knowledge is essential for tissue engineering applications in order to better understand the impact of gel-embedded cells on the delivery of different therapeutics ingredients.