The Polymer Society of Korea

Abstract

Reduction-responsive interpenetrating polymer network (IPN) microspheres composed of alginate and thiolated TEMPO-oxidized cellulose nanofibers (Th-TCNF) were developed for localized Mitoxantrone (MIT) delivery. Th-TCNF was synthesized via cysteamine coupling and confirmed by NMR and FT-IR. Spray-dried microspheres were dual-crosslinked through coordination and disulfide bond formation, creating a mechanically reinforced structure with improved thermal stability. SEM and elemental mapping confirmed a dense IPN morphology and successful network interpenetration. XPS verified the redox-responsive cleavage of disulfide bonds. In vitro, MIT-loaded IPN microspheres showed sustained reduction-triggered release and potent cytotoxicity against MDA-MB-231 cells. In vivo, intratumoral injection significantly reduced tumor growth, inducing extensive necrosis and apoptosis without systemic toxicity. This platform offers a promising strategy for enhanced, localized chemotherapeutic efficacy.