A comparative study into the fabrication of carboxymethyl cellulose-polycaprolactone core-shell nanofibres via pressurised gyration and electrospinning.

Abstract

A comparative study was conducted into the fabrication of polycaprolactone (PCL)/carboxymethyl cellulose (CMC) and PCL/CMC-polyvinyl alcohol (PVA) core-shell nanofibres using co-axial electrospinning (ES) and pressurised gyration (PG). Ibuprofen and ibuprofen sodium were used as model drugs. The influence of solution composition and processing parameters on fibre morphology, internal structure, thermal properties, encapsulation efficiency, production rate, yield and drug-release behaviour was evaluated. Uniform nanofibres were obtained for most formulations by both methods, although occasional bead formation was observed in PG-fabricated PCL/CMC fibres. Scanning electron microscopy showed the PG fibres to have larger diameters than those obtained from ES, and transmission electron microscopy and confocal microscopy confirmed well-defined core-shell structures. ES achieved high production yields of 93-98% and good morphological control, whereas PG enabled much higher production rates (ca. 400 mg min-1 cf. 2-3 mg min-1 from ES), indicating scalability despite lower yield (around 50%). Drug-loading studies demonstrated encapsulation efficiencies of 54-109%, with ES giving markedly higher efficiencies than PG. Compared with monolithic fibres, core-shell fibres generally moderated early release, particularly in ES systems, while PG release behaviour was formulation-dependent. From these findings, it is clear that both ES and PG represent viable routes for producing PCL/CMC-based core-shell nanofibres. ES provides superior yield and structural control, while PG offers a significant advantage in production rate. These complementary characteristics, together with favourable drug-encapsulation and release performance, highlight the potential of PCL/CMC-based core-shell nanofibres as versatile and scalable platforms for biomedical drug-delivery applications.