Green Synthesis of Quercetin-Coated Ecofriendly Zirconium Oxide Nanoparticles and Evaluating its <i>in vitro</i> Biological Activities

The development of nanomaterials using green synthesis methods is gaining attention due to their potential to reduce environmental pollution and health risks associated with traditional chemical synthesis methods. Among the various transition metals, zirconia has gained significant interest as filling materials and implants in dentistry due to its excellent mechanical and chemical properties. In this study, we developed ecofriendly zirconium oxide nanoparticles using Biancaea sappan extract as a capping agent and then functionalized them with Quercetin. Further, their anti-inflammatory property and hemocompatibility were evaluated to target their application as filling materials. The biogenic zirconium oxide nanoparticles (B-ZrO 2 NPs) and quercetin functionalized biogenic zirconium oxide nanoparticles (BQZN) were characterized by UV–Vis Spectroscopy (UV–Vis), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy X-ray analysis (EDX). B-ZrO 2 NPs showed maximum absorbance at 267[Formula: see text]nm and 383[Formula: see text]nm. FTIR showed characteristic stretching at 3381[Formula: see text]cm[Formula: see text], confirming the O–H group in the extract and Quercetin used for BQZN formation. The FTIR spectra of BQZN displayed the presence of the characteristic peaks observed in the spectra of B-ZrO 2 NPs and Quercetin. The broad XRD pattern confirmed the amorphous nature of the zirconia. SEM revealed the spherical morphology of B-ZrO 2 NPs and BQZN with a size range of around 90[Formula: see text]nm and 120[Formula: see text]nm, respectively. EDAX of BQZN revealed the presence of 45.7[Formula: see text]wt.% Zr, 32.9% oxygen and 21.4% of carbon. In vitro bioactivity studies revealed that BQZN exhibited significant anti-inflammatory activity, as evidenced by the inhibition of protein denaturation. The nanoparticles were also demonstrated for their hemocompatibility with erythrocytes. These findings highlight the potential of BQZN as a promising hemocompatible dental filling with significant anti-inflammatory properties. Further in-depth in vivo studies are required to fully understand their efficacy and toxicity.