Green synthesis of cannabinoids loaded gold nanoparticles displaying enhanced anti-cancer properties

This study investigates the anti-cancer potential of cannabinoids loaded onto gold nanoparticles (AuNPs) for targeted cancer treatment. We adopted a multifaceted approach to explore and design this nano system, encompassing its synthesis, physicochemical characterization, stability assessment, and evaluation of anticancer efficacy in 2D and 3D in vitro models. In this research, we have demonstrated that two highly hydrophobic phytocannabinoids like delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), can be loaded on the surface of AuNPs with a one-pot synthesis protocol using trisodium citrate and l-tyrosine as a reducing and stabilizing agents. l-tyrosine plays a crucial role in cannabinoid loading, stability, and shelf life of the AuNPs. After synthesis, the cannabinoid-loaded nanoparticles were characterized with UV–vis spectroscopy, dynamic light scattering (DLS), dark field hyperspectral microscopy, and electron microscopy. The AuNPs function as a scaffold for the attachment and enhanced transport of both cannabinoids inside cancer cells, thus increasing their bioavailability. Hyperspectral microscopy was used to confirm AuNPs uptake. IC₅₀ values in SK-BR-3 human breast cancer cell line for both THC and CBD loaded onto AuNPs were lower by 70.75 % and 37.04 % than those of the aqueous suspension of pure molecules. Compared to the aqueous suspension of pure cannabinoids, this approach induced and enhanced cancer cell death more efficiently. This enhanced efficacy was associated with a decline in cell viability, which is attributed to apoptosis, as indicated by flow cytometry results. Our findings offer a significant step towards the green design and utilization of AuNPs to deliver cannabinoids into cells efficiently.