Background: Submicron particles (SMPs), as novel bionanomaterials, offer complementary benefits to their conventional nano-counterparts. Aim: To explore zinc oxide (ZnO) SMPs' bioimaging and anticancer potentials. Materials & methods: ZnO SMPs were synthesized into two shapes. Fluorescent spectrum and microscopy were studied for the bioimaging property. Wound healing and Live/Dead assays of glioblastoma cells were characterized for anticancer activities. Results: ZnO SMPs exhibited a high quantum yield (49%) with stable orange fluorescence emission. Both morphologies (most significant in the rod shape) showed tumor-selective properties in cytotoxicity, inhibition to cell migration and attenuating the cancer-upregulated genes. The tumor selectivity was attributed to particle degradation and surface properties on pH dependency. Conclusion: The authors propose that ZnO SMPs could be a promising anticancer drug with tunable, morphology-dependent properties for bioimaging and controlled release.
Keywords: ZnO; anticancer; bioimaging; morphology dependency; pH dependency; submicron particle; zeta potential.
Submicron particles (SMPs) are a novel nanomaterial whose total size is microscale (around one-millionth of a meter), but at least one dimension is nanoscale (around one-billionth of a meter). Their combined micro- and nanoscale properties are complementary, which can be an improvement on their conventional nano-counterparts. The aim of this study was to explore the bioimaging and anticancer properties of zinc oxide (ZnO) SMPs. ZnO SMPs were synthesized in two shapes: rod-shaped and flower-shaped. The fluorescence spectra and microscopy images were studied to investigate their potential for imaging applications, and wound healing and viability assays of glioblastoma cells were used to characterize anticancer activity. ZnO SMPs exhibited strong and stable orange fluorescence emission. Both shapes of ZnO SMPs showed tumor-selective toxicity, inhibition to cell migration and attenuating the cancer-upregulated genes; however, these effects were more significant for the rod-shaped particles. The tumor selectivity was attributed to pH-dependent particle degradation related to surface properties. The authors therefore propose that ZnO SMPs could be a promising anticancer drug with tunable, morphology-dependent properties for bioimaging and controlled release.