3D printed core-shell hydrogel fiber scaffolds with NIR-triggered drug release for localized therapy of breast cancer.

Localized therapy using hydrogels-based drug delivery system (DDS) is a promising strategy for the treatment of diseases such as cancer in superficial tissues. In this study, we presented a facile method to prepare core-shell hydrogel fibers/scaffolds with controlled drug delivery and designed structures for the treatment of the residual breast cancer and prevention of local recurrence after surgery. Mixtures of polydopamine (PDA) and concentrated alginate inks (15.3 wt%) as the shell layer, and drug-loaded temperature-sensitive hydrogels as the core part were co-injected and coaxial 3D printed into core-shell hydrogel fibers and scaffolds. Under near infrared (NIR) irradiation, PDA with excellent photothermal effect could raise the temperature of core-shell fibers, which induced the gel-sol transition of the core gels, and subsequently resulted in the drug release from the loosened hydrogel network. The photothermal effect and the released drugs could eliminate cancer effectively. Thus, our prepared core/shell fibers and scaffolds with NIR-triggered on-demand drug release would be promising candidates to fill the cavity of breast tissues after surgical resection of cancer achieving a therapeutic effect for the residual and recurred cancer.