Multi-functional bismuth-doped bioglasses: combining bioactivity and photothermal response for bone tumor treatment and tissue repair

TLDR

Treating large bone defects from tumor surgery usually requires separate hyperthermia and bioactive implants, making it difficult to combine these functions into a single material. The study aims to develop a Bi‑doped bioactive glass that integrates photothermal hyperthermia and bioactivity to treat bone tumors and promote bone repair in one material. The glass incorporates Bi species whose photothermal effect is tuned by manipulating radiative and non‑radiative pathways through photoluminescence quenching or glass network depolymerization, enabling simultaneous hyperthermia and bioactivity. In vitro and in vivo studies show that the Bi‑doped bioglass exhibits high photothermal efficiency, kills bone tumor cells under NIR illumination, is biocompatible, and promotes osteogenic proliferation, differentiation, and mineralization, demonstrating its potential as a multifunctional bone‑treatment material.

Abstract

Treatment of large bone defects derived from bone tumor surgery is typically performed in multiple separate operations, such as hyperthermia to extinguish residual malignant cells or implanting bioactive materials to initiate apatite remineralization for tissue repair; it is very challenging to combine these functions into a material. Herein, we report the first photothermal (PT) effect in bismuth (Bi)-doped glasses. On the basis of this discovery, we have developed a new type of Bi-doped bioactive glass that integrates both functions, thus reducing the number of treatment cycles. We demonstrate that Bi-doped bioglasses (BGs) provide high PT efficiency, potentially facilitating photoinduced hyperthermia and bioactivity to allow bone tissue remineralization. The PT effect of Bi-doped BGs can be effectively controlled by managing radiative and non-radiative processes of the active Bi species by quenching photoluminescence (PL) or depolymerizing glass networks. In vitro studies demonstrate that such glasses are biocompatible to tumor and normal cells and that they can promote osteogenic cell proliferation, differentiation, and mineralization. Upon illumination with near-infrared (NIR) light, the bioglass (BG) can efficiently kill bone tumor cells, as demonstrated via in vitro and in vivo experiments. This indicates excellent potential for the integration of multiple functions within the new materials, which will aid in the development and application of novel biomaterials.