TiO₂ prolatenanospheroids (PNSs) may be photosensitizers (PSs), which act by catalyzation of hydroxyl radical (^∙OH) formation upon light illumination. ^∙OH might, in turn, contribute to killing of cancer cells. On the other hand, there is great concern about toxicity in the dark of TiO₂ nanoparticles in general. In this work, we have investigated the biocompatibility of TiO₂ PNSs of the anatase crystal form (length between 100 and 300 nm and width 50 nm) in the dark with immune cells and light-induced cytotoxicity on several cancer cell lines. The effects of the treatment of different cell lines with several concentrations of TiO₂ PNSs suspensions showed the specifics of cells’ viability and the intracellular localization. The results of in vitro studies obtained by cytotoxicity assays adjusted to individual cell lines’ metabolism point towards the biocompatibility of TiO₂ PNSs at low and moderate concentrations in the dark, which neither kill the cells, nor induce activation of the immune system cells. Laser scanning confocal microscopy revealed that PNSs are taken up by cells, and insight into the intracellular distribution was obtained in this study.

TiO ₂扁豆类球体（PNSs）可以是光敏剂（PSs），它们在光照下通过催化羟基自由基（^∙ OH）的形成起作用。^∙ OH可能反过来有助于杀死癌细胞。另一方面，通常非常关注TiO ₂纳米粒子在黑暗中的毒性。在这项工作中，我们研究了在黑暗中具有免疫细胞的锐钛矿晶型（长度在100到300 nm之间，宽度在50 nm之间）的TiO ₂ PNSs的生物相容性，以及几种癌细胞系的光诱导细胞毒性。几种浓度的TiO ₂处理不同细胞系的效果PNSs悬浮液显示了细胞活力和细胞内定位的细节。通过针对细胞系代谢进行调整的细胞毒性试验获得的体外研究结果表明，在黑暗中处于中低浓度时，TiO ₂ PNS的生物相容性不会杀死细胞，也不会诱导免疫系统细胞的活化。激光扫描共聚焦显微镜显示PNSs被细胞吸收，并且在这项研究中获得了对细胞内分布的见识。