Ionically cross-linked micro-sized hydrogels with encapsulated drug: Structure, cell uptake kinetics and cytotoxicity

Micro-sized hydrogels synthesized by electrostatic cross-linking of anionic alginate with Ca²⁺ cations were additionally loaded with cationic fluorescent dye Rhodamine 6B or cationic antitumor antibiotic doxorubicin. Forming complexes with Ca²⁺ alginate hydrogels, doxorubicin retained or even reduced its toxicity to tumor and normal cells. The results can be used to design containers for the encapsulation and delivery of drugs and control their interaction with cells.