Engineering Three-Chamber Core-Sheath Cellulose Acetate Nanofibers via Multifluid Electrospinning for Enhanced Wettability and Tunable Initial Drug Release Behavior.

Traditional materials are often constrained by their structural and functional limitations. To address this challenge, multifluid electrospinning has emerged as an advanced nanofabrication technique capable of producing complex structures with enhanced performance. Inspired by rocket stage separation, we utilized cellulose acetate, a biomacromolecule derivative, as the polymer matrix to fabricate complex three-chamber core-sheath nanofibers with TEM-verified structures and enhanced performance. The surface wettability of the fibers was effectively tuned by adjusting the polyvinylpyrrolidone (PVP) concentration in the outermost layer, where a higher PVP content enabled a rapid transition from hydrophobic to hydrophilic states. Furthermore, the strategic colocalization of PVP and drug in the sheath layer yielded a biphasic release profile, characterized by an initial burst followed by a sustained release phase, which successfully eliminated the tailing effect in the late stage. Increasing the drug loading in the outer layer from 1% to 3% significantly enhanced the initial release amount from 65.15% ± 11.19% to 79.26% ± 0.42%. This work establishes a robust material design strategy based on structural and componential control, offering new insights into the development of high-performance nanofibrous systems for tailored drug delivery and functional applications.