Injectable visible light-cured glycol chitosan hydrogels with controlled release of anticancer drugs for local cancer therapy in vivo: a feasible study

Currently available chemotherapy is associated with serious side effects, and therefore novel drug delivery systems (DDSs) are required to specifically deliver anticancer drugs to targeted sites. In this study, we evaluated the feasibility of visible light-cured glycol chitosan (GC) hydrogels with controlled release of doxorubicin⋅hydrochloride (DOX⋅HCl) as local DDSs for effective cancer therapy in vivo. The storage modulus of the hydrogel precursor solutions was increased as a function of visible light irradiation time. In addition, the swelling ratio of the hydrogel irradiated for 10 s (GC10/DOX) was greater than in 60 s (GC60/DOX). In vitro release test showed that DOX was rapidly released in GC10/DOX compared with GC60/DOX due to the density of cross-linking. In vitro and in vivo tests including cell viability and measurement of tumor volume showed that the local treatment of GC10/DOX yielded substantially greater antitumor effect compared with that of GC60/DOX. Therefore, the visible light-cured GC hydrogel system may exhibit clinical potential as a local DDS of anticancer drugs with controlled release, by modulating cross-linking density.