Nanoarchitectonics of (110) directed polyethylene glycol stabilized cerium nanoparticles for UV filtering applications

Abstract

The use of zinc oxide (ZnO) and titanium oxide (TiO2) nanoparticles in ultraviolet (UV) filters can cause serious health issues due to their genotoxicity and cytotoxicity effect. Recent research on cerium oxide (CeO2) nanoparticles has demonstrated their biocompatible nature, excellent antioxidant and ultraviolet–visible (UV–Vis) absorption properties. CeO2-based nanocomposite materials or nano-architectures can offer uniform absorptive properties, therapeutic skin effect and easy skin application. In this study, cerium oxide-polyethylene glycol (CeO2-PEG) nano-architecture was prepared by hydrothermal processing with the aim to improve stability, antioxidant properties, and enhance UV absorption for UV filtering applications. The morphology study of the developed nanocomposite revealed the formation of polymer bands with well-dispersed CeO2 nanoparticles. The nanocomposite structure has exhibited excellent UV absorption in the UV range 200–400 nm due to decrease in optical band gap in comparison to the naked CeO2 NPs. The evaluation of the photocatalytic activity (PCA) of the nanocomposite structure against P25 photocatalyst and ZnO nanoparticles showed no dye (crystal violet) degradation on UV irradiation. Hence, PCA assay verified the absence of ROS generation and increased stability of the nanostructure under UV irradiation. The investigation of antioxidant properties of the Ce-PEG nanocomposite by a dichlorofluorescein (DCF)-based assay revealed sufficient intracellular ROS scavenging in comparison to N-acetylcysteine (NAC) and H2O2 only assays. In vitro toxicity evaluation of Ce-PEG nanocomposite towards non-malignant human keratinocyte cell line (HaCaT) revealed a non-significant cell mortality ~ 10% of control at a dosage of 50 mg L−1. The nanocomposite structure also exhibited excellent UV protection for HaCaT cells under UV irradiation conditions compared to P25. Our findings suggest that the developed nanocomposite combined the antioxidant and UV absorption properties of CeO2 and skin emollient role of (PEG), and hence offered a novel biocompatible and multifunctional structure for sunscreens and therapeutic skin product. Graphical abstract