Design of Chemically Stable Pinostrobin-Gold Nanoparticles with Robust Core-Shell Structures: Exploring Antioxidant and Anticancer Mechanisms in Cancer Cells

This study presents a novel approach in the synthesis and characterization of pinostrobin-conjugated gold nanoparticles (Pin-AuNPs) to enhance therapeutic efficacy. Pinostrobin, a flavonoid from Boesenbergia rotunda, a traditional medicinal plant, has known antioxidant and anticancer properties but suffers from limited bioavailability and stability. Conjugation with gold nanoparticles aims to overcome these limitations, representing a new discovery in optimizing herbal bioactives for medical applications. Pinostrobin was first isolated from the rhizome of B. rotunda through solvent extraction and purification processes. In this study, pinostrobin-conjugated gold nanoparticles (Pin-AuNPs) were synthesized and evaluated for their antioxidant and anticancer applications. Characterization of Pin-AuNPs was performed using TEM, FT-IR, UV-Visible spectroscopy, and DLS. Antioxidant activity, evaluated via the ABTS assay, showed Pin-AuNPs had stronger radical scavenging (IC50 0.94 µg/mL) than free pinostrobin or AuNPs. Cytotoxicity tests on Huh7it liver cancer cells demonstrated significantly improved anticancer effects, with 97.68% inhibition at 200 µg/mL and an IC50 of 18.38 µg/mL, much lower than free pinostrobin (>200 µg/mL). The enhanced bioactivity is likely due to improved cellular uptake and stress induction by the conjugated nanoparticles. This is the first report of Pin-AuNPs with both superior antioxidant and anticancer effects, suggesting promising applications in nanomedicine and herbal-based cancer therapy.