Wet-electrospun porous freeform scaffold enhances colonisation of cells.

Osteoarthritis is a degenerative disease characterized by the progressive deterioration of articular cartilage. Electrospun scaffolds have shown promise in the regeneration of degraded areas due to their highly interconnected and extracellular matrix-mimicking structures. However, current electrospun scaffold-based therapies are limited by the constraints of 2D cell culture. In this study, a novel wet-electrospinning technique to generate polycaprolactone (PCL) porous 3D scaffolds was developed. The wet-electrospun yarns were collected via vortex, allowing for loosely interconnected yarns, thereby enhancing cell infiltration. Sodium hydroxide (NaOH) treatment was used to introduce carboxyl groups on PCL fibres, followed by gelatin conjugation via N-hydroxysuccinimide (NHS) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) crosslinking. Comparative analysis between conventional electrospun 2D dense and wet-electrospun 3D porous scaffolds revealed significant advantages in porosity, reaching up to 99.5 % in the 3D matrices. Subsequent in vitro evaluations demonstrated full-thickness cell infiltration in the 3D high-porosity scaffold after 7 days, as confirmed by SEM and confocal images. Further analysis on day 14 revealed the deposition of glycosaminoglycans (GAGs) and collagen. This research introduces a novel technique for fabricating high-porosity scaffolds that facilitate full-thickness 3D cell culture. These novel high-porosity, gelatin-conjugated scaffolds enhance cell colonisation and deposition. Overall, these high-porosity scaffolds overcome the limitations of conventional electrospinning, enabling 3D cell culture and offering new opportunities for cartilage regeneration and reconstruction.