MERLN Summer Talks
Electrospun polymer fibers for drug delivery from atopic skin to wound dressing and tissue engineering
Skin wound closer is still one of the major problems in regenerative medicine similarly to skin regeneration. Electrospun polymer fibers are one most studied material for tissue engineering as it is characterized by high surface area to the mass ratio. The porosity of electrospun scaffolds reaches often more than 90 %, which gives an enormous advantage in drug delivery. Moreover, randomly oriented electrospun fibers allowed for a natural reflection of the extracellular matrix (ECM) structure enhancing the interaction of cells. Apart of the major application in tissue regeneration the electrospun fibers are used as skin patches to treat eczema. Various geometries of membranes (aligned, random, nano- and microfibers) and polymers (PVB, PCL, PHBV, PI, PA6, PS) were used to design patches with controlled oil release over a few hours. The experimental studies in vitro and in vivo have been confirmed with the numerical simulations of oil transport through the porous patches. The in vitro studies, including proliferation and scratch tests, were performed mainly with keratinocytes (HaCaT cell line). The spectroscopy methods were employed to verify the hyaluronic acid (HA), urea, cholesterol and chlorine delivery to skin.
The results indicate the beneficial effects of the electrospun patches and their high biocompatibility. We show that oil spreading and transport in patches depends on the sizes of the fibers and pores, their surface properties and porosity. The electrospun patches can be easily applied overnight for protecting the skin and improving the comfort of people suffering from various acne and eczema problems. We find the possibility of delivering urea, chlorine or cholesterol to enhance skin treatment via combination of various manufacturing steps.
Moreover, electrospinning gives many opportunities to create composite fibers by selecting co-axial or side-by-side nozzle or meshes by using two nozzles at the same time or in the layer-by-layer approach. Eventually, the various strategies were applied to create electrospun fibers with the desired surface properties such as mechanical, surface potential to find personalized solutions for wound healing applications for delivering HA. Importantly, this release of HA increase keratinocyte activity as well their proliferation leading to accelerated wound closure rate in the scratch tests. The designed HA-coated electrospun scaffolds demonstrate the great potential of surface-modified electrospun polymer fibers for wound healing.
Electrospinning also allows us to control surface charges on created scaffolds. A comprehensive investigation of distinct mechanisms to modulate surface potential in electrospun fibers was performed. We examined the influence of polymer chain orientation induced by alternating voltage polarity during electrospinning. We also explored material diffusion between core and shell phases in coaxial fibers. Most recently, we evaluated the impact of incorporating two-dimensional conductive nanomaterials—reduced graphene oxide (rGO) and titanium carbide MXenes (Ti₃C₂Tₓ), on surface potential of polymer fibers. In summary, our findings highlight the pivotal role of scaffold surface potential in mediating cellular responses and underscore the importance of tailored electrospun fibre design to accelerate tissue regeneration processes.
Acknowledgements
Research supported by Programme for Research and AGH University, Initiative of Excellence – Research University” (IDUB).