PhD Scientific Days 2024

Theoretical and Translational Medicine I.

Synergistic properties of polysuccinimide/poly(lactic acid) co-electrospun and blended-electrospun nanofibres

Text of the abstract

Integrating surgical implants in a biological host is an essential but challenging task in regenerative medicine. If implants do not support proper cell adhesion, infiltration, and migration, the immune system can respond by forming a fibrous capsule around it, isolating and rendering it ineffective. To overcome this obstacle, researchers are exploring blend and composite materials. Poly (lactic acid) (PLA) is popular in biomedical applications for its biocompatibility, chemical stability, and affordability, despite its hydrophobic nature, poor cell adhesion, and slow degradation rate. Polysuccinimide (PSI), on the other hand, is renowned for its superior cell adhesion, biocompatibility, and quick degradation.
Our goal was to fabricate an electrospun mesh incorporating both a fast-degrading (PSI) and a slow-degrading (PLA) component using different electrospinning set-ups.
We used co-electrospinning and blend-electrospinning techniques to produce polysuccinimide/polylactic acid (PSI/PLA) meshes, which were then subjected to chemical, physical, and mechanical characterisation.
The meshes were successfully produced, with scanning electron microscopy confirming no structural defects. While the co-electrospun meshes were flat, the blend-electrospun meshes exhibited a three dimensional structure. Fiber diameters averaged 580 ± 140 nm for co-electrospun and 650 ± 110 nm for blend-electrospun meshes. ATR-FTIR analysis confirmed the presence of both materials. Compared to pure PLA meshes, the co-electrospun meshes showed increased hydrophilicity and higher specific loading capacity. On the other hand, the blend meshes underperformed. The in vitro degradation test revealed that the PSI component degrades within a week, whereas the PLA component remained stable for over four weeks.
The co-electrospun PSI/PLA meshes showed enhanced strength, suggesting a synergistic relationship compared to the blend-electrospun meshes, which performed poorly but exhibited a three dimensional structure. The improved hydrophilicity in the co-electrospun meshes indicates potential for better cell adhesion. It was clear that PSI degrades much faster than PLA. Both meshes can be used for different applications according to their advantages.