Combined Synthesis of Cerium Oxide Particles for Effective Anti-Bacterial and Anti-Cancer Nanotherapeutics

Kochiae Fructus has been widely used in Chinese Herbal medicine to treat various diseases. We report a rapid and eco-friendly approach for cerium oxide (CeO₂) nanoparticles (NPs) synthesis using the extract of medicinally important plant "Kochiae Fructus", and the synthesized NPs were named KF-CeO₂ NPs.

Various spectroscopic approaches such as transmission electron microscope (TEM), powder X-ray diffraction (XRD), and energy-dispersive X-Ray (EDX) were used to characterize the KF-CeO₂ NPs effectively. The antibacterial and biofilm inhibition activity of KF-CeO₂ NPs against Gram-positive and Gram-negative multi-drug resistant (MDR) bacteria was determined using the serial dilution method and XTT assay. KF-CeO₂ NPs were assessed for anticancer activity against HeLa cancer cells using an MTT assay. Cytobiocompatibility was determined in two normal cell lines (3T3 and hMSC).

The average size of the KF-CeO₂ NPs was 11.3 ± 3.9 nm with spherical morphology. KF-CeO₂ NPs demonstrated a greater than 95% bactericidal efficacy against MDR microorganisms. In addition, KF-CeO₂ NPs strongly suppressed (more than 79%) the biofilms of MDR bacteria, indicating their potential for addressing antibiotic resistance issues. Compared to Kochiae Fructus extract and CH-CeO₂ NPs, they exhibited significant cytotoxic effects (35.60% cell viability) on HeLa cancer cells. In addition, the KF-CeO₂ NPs were shown to be highly biocompatible with hMSC and 3T3 cell lines (85.13% and 81.17% cell viability, respectively), suggesting that they may be employed in biological systems.

These data indicate that KF-CeO₂ NPs synthesized using Kochiae Fructus extract are promising alternative treatments for MDR. In addition, this study will give the potential for the sustained development of biocompatible NPs with enhanced biological capabilities derived from vital pharmaceutical plants.