Alginate-azo/chitosan nanocapsules in vitro drug delivery for hepatic carcinoma cells: UV-stimulated decomposition and drug release based on trans-to-cis isomerization

In this study, a nanocapsule (AL-azo/CH) was prepared with the anionic alginate-azo (AL-azo) and cationic chitosan (CH) via layer-by-layer method. Doxorubicin hydrochloride (DOX), an anticancer drug, was entrapped inside the AL-azo nanocapsules to form the DOX-loaded nanocapsules (DOX/AL-azo/CH). When the DOX/AL-azo/CH nanocapsules were irradiated with 365-nm light, the electrostatic attraction between the layers would be weakened as the trans-to-cis isomerization of AL-azo, which would lead to the UV-responsive decomposition and drug-release. Furthermore, cellular experiments showed that DOX/AL-azo/CH nanocapsules could be endocytosed by the HepG2 cells, and the confocal laser scanning microscope images showed that the DOX fluorescence intensity became stronger with the prolonging of irradiation time, indicating that the intracellular DOX-release could be controlled by UV irradiation. The AL-azo/CH nanocarriers were UV-triggered decomposition and drug-release, which stepped further towards the next-generation of nano-therapeutics with spatial and temporal external control in the field of polysaccharide.