The effects of biogenic bismuth oxide nanoparticles on radiosensitivity of gastric cancer cells

Gastric cancer is the ۵th most common neoplasm and the ۳rd most deadly cancer worldwide. In this study, we produced bismuth oxide (Bi۲O۳) and bismuth oxide-zeolite nanocomposites (Bi۲O۳-Z NCs) using Vibrio sp. VLC bacteria and investigated their effects on radiosensitivity of human gastric cancer cells.After synthesis of Bi۲O۳ NPs and Bi۲O۳-Z NCs by Vibrio sp. VLC bacteria, the characterization of NPs were evaluated using UV-visible, FTIR, XRD, DLS, Zeta potential, TEM and FESEM. Then, MKN-۴۵ cells, a human gastric adenocarcinoma cell line, were SUHWUHDWHG ZLWK ۲۵ J/PO %L۲O۳ NPs (in two forms of heated and non-heated) and Bi۲O۳-Z NCs, while bismuth salt and zeolite were considered as controls. After ۲۴ h, cells were exposed to ۲۰۰, ۴۰۰ and ۶۰۰ centigray (cGy) of X-radiation and recovered for ۷۲ h. At the end, viability of cells was determined by resazurin assay.Findings of present research indicated that Bi۲O۳ NPs (non-heated) as well as bismuth salt and zeolite pretreatments increased the effects of ۲۰۰ cGy radiation. Moreover, Bi۲O۳ NPs (heated) significantly (p <۰.۰۵) improved the sensitivity of MKN-۴۵ cells to ۴۰۰ cGy X-ray. More interesting results were observed when ۶۰۰ cGy radiation was applied, as Bi۲O۳ NPs (heated) and Bi۲O۳-Z NCs significantly (p <۰.۰۰۰۱ and p <۰.۰۵, respectively) enhanced radiosensitivity of cells.In conclusion, obtained results revealed that Bi۲O۳ NPs and Bi۲O۳-Z NCs could act as potent radio sensitizers, although more investigation on other gastric cell lines is required to confirm our findings.