Bismuth containing 58S bioglass amplifies radiation induced cell death and promotes bone regeneration

With the aim to improve local cancer radiotherapy while maintaining the tissue-regenerative properties of the glass, bioglasses with the composition (58 − x )SiO 2 –36CaO–6P 2 O 5 – x Bi 2 O 3 (where x = 0, 2, 5, or 10 wt%) were synthesized using the sol-gel method. The obtained glasses were labeled as BG, 2Bi-BG, 5Bi-BG, and 10Bi-BG, respectively. Numerous characterization techniques, including XRD, FTIR, SEM-EDX, and DLS were utilized. MTT, fluorescence microscopy, and flow cytometry were used to assess biocompatibility, osteointegration, and sensitization enhancement ratio (SER), respectively, after bismuth addition. A broad hump centered at 12° 2θ, indicating the amorphous, glassy nature of the products. Doped samples showed additional weak reflections confirming the presence of Bi 2 O 3 and quantifying its proportion within the material. Zeta potential measurements revealed values ranging from − 11.9 to − 14.2 mV ( p < 0.01) with increasing bismuth content. This may have influenced cell behavior, specifically adhesion. In vitro, three-times more osteoblasts adhere to 10Bi-BG surfaces than BG surfaces. Bioactivity, in terms of apatite formation ability, was verified in vitro through immersion in SBF. Finally, combining 10Bi-BG with radiation significantly induced greater cell death than radiation alone. The SER of 10Bi-BG was approximately 2.6. Consequently, bismuth-doped 58 S bioglasses represent a promising bifunctional platform capable of simultaneously amplifying localized radiotherapy efficacy and stimulating bone tissue regeneration in the comprehensive management of bone malignancies.