Fibrous CaF2:Yb,Er@Sio2-PAA 'tumor patch' with NIR-triggered and trackable DOX release

Smart localized drug delivery systems (LDDSs), with stimuli-responsive properties, offer tremendous opportunity for personalized cancer chemotherapy. In our work, an implantable 'tumor patch', consisting of upconversion (UC) photoluminescent CaF2:Yb,Er nanoparticles embedded within silica nanofibers (CaF2:Yb,Er@Sio(2)), was designed and synthesized for doxorubicin (DOX) delivery. DOX loading capacity of the fiber mesh was remarkably enhanced with assist of polyacrylic acid (PM) functionalization. PM modified CaF2:Yb,Er@Sio(2) nanofibers presented highly corresponding optical response to DOX release kinetics. Accelerated drug release in acidic condition induced more rapid increase in the spectral intensity ratio of green to red emission (I-550/I-660), and vice versa. More importantly, under the irradiation of NIR (808 nm) laser, DOX release kinetics and consequently the in-vitro anti-cancer efficacy were enhanced. This study has thus offered another new implantable LDDS with NIR-triggered and monitored DOX delivery for personalized protocols in tumor chemotherapy. (C) 2017 Elsevier Ltd. All tights reserved.