Potential of moderate-Z superparamagnetic nanoparticles in improving the efficacy of cancer theranostics

Abstract

The radiosensitization studies of superparamagnetic nanoparticles (SPMNPs) are fewer than those of high-Z NPs due to the notion that only high-Z NPs can enhance the radiation damage through the physical effects. Recent studies have shown that, in addition to physical effects, chemical and biological effects of NPs contribute equally to the observed radiation damage enhancement. Therefore, in this study, the cytotoxicity, anticancer, and radiosensitization potential of the hydrothermally synthesized moderate-Z Zn0.4M0.6Fe2O4 SPMNPs (M = Mn, Ni, Cu, and Zn) against HT-29 Colon cancer cells were studied. The SPMNPs were characterized by XRD, XPS, VSM, FTIR, FE-SEM, and DLS techniques. The observed values of saturation magnetization of the SPMNPs were explained by cationic distribution obtained via Rietveld refinement and deconvolution method from XRD and XPS results, respectively. The cytotoxicity, anticancer, and radiosensitization potential of the SPMNPs against astrocytes and HT-29 colon cancer cells were evaluated by MTT assay and clonogenic assay. The SPMNPs exhibited differential cell killing, anticancer, and radiosensitization potential in colon cancer cells. Zn0.4Mn0.6Fe2O4 SPMNPs exhibited a significant damage enhancement of 3.67 fold compared to gamma radiation alone in cancer cells. However, in vivo studies are required before considering these NPs for clinical studies.