Evaluation of the in vitro cytotoxicity and drug delivery of ytterbium (III)-doped versatile bioactive glasses for cancer treatment

In this study, the in vitro mineralization, as well as an antitumor drug (fluorouracil) delivery of sol-gel-derived bioactive glasses doped with a lanthanide (III) element (Yb³⁺), have been investigated. Additionally, the cytotoxicity of the related bioactive glasses was examined against osteosarcoma SaOS-2 and osteoblastic MC3T3-E1 cell lines under in vitro conditions. The results demonstrated that the bioactive glass samples containing rare earth element did not induce cytotoxic effects on the mentioned cell lines for up to 7 days. An increase in alkaline phosphatase enzyme activity was observed for all samples during the incubation period. Drug loading experiments showed that the anticancer drug amount adsorbed onto the bioactive glass powders at pH 7.4 ranged between 25% and 35%. Based on the drug delivery studies conducted in phosphate-buffered saline solution at pH 7.4 and 5.5, cumulative drug release from the bioactive glass powders after 500 h was between 60% and 70% at neutral pH. A higher drug delivery was observed at lower pH value. The drug release kinetics were found to be consistent with the Higuchi model. The findings of this study indicate that bioactive glasses containing trivalent ytterbium possess suitable biological properties for use in biomedical applications and they offer improved biocompatibility providing an ideal environment for bone regeneration.