Polycaprolactone nanofiber mesh with adhered liposomes as a simple delivery system for bioactive growth factors

Polycaprolactone (PCL) nanofibers were prepared using electrospinning and functionalized with liposomes containing growth factors by simple surface adhesion. A tight interaction between the liposomes and PCL nanofibers has been clearly demonstrated. Additionally, the interaction of the liposomes with the PCL nanofibers was visualized by FESEM. The potential of the liposome-immobilized scaffold as a delivery system for synthetic growth factors, and as a suitable system for mesenchymal stem cells (MSCs) adhesion and proliferation, was evaluated by confocal microscopy, DNA synthesis rate and dsDNA amount determination. The results showed that the growth factors adhered to the surface of the PCL nanofibers stimulated cell proliferation mainly up to day 7, and that afterwards their effect was significantly lower. By contrast, the release of growth factors from liposomes resulted in gradual proliferation of MSCs throughout the whole experiment. Moreover, the functionalized nanofibers stimulated type II collagen production, which was confirmed by immunohistochemical staining using monoclonal antibody against type II collagen. The study has indicated that growth factor-enriched liposomes adhered to the PCL nanofiber system could be useful as a drug delivery tool in various biomedical applications.