Protein assisted one pot controlled synthesis of monodispersed and multifunctional colloidal silver‑gold alloy nanoparticles

Abstract

Here, we prepared gold‑silver alloy nanoparticle (AgAuNPCS) of ~8.5 nm mean size via one-pot biogenic synthesis using casein as reducing as well as capping agent and explored its potential in various biomedical applications using curcumin (CUR) as a drug delivery agent. When we prepared the nanoconjugate with curcumin (AgAuNPCS-CUR) of 10.5 nm mean size via chemical activation followed by loading, it demonstrated excellent curcumin loading capacity (221.19 mg/g). Furthermore, AgAuNPCS-CUR exhibited pH driven CUR release up to a maximum of 85% at a pH 6.0. We also observed its significant storage stability up to 30 days at 4 °C. When applied in cancer cells, the nanoconjugate demonstrated higher cytotoxicity to multiple cancer cells (MCF-7, MDAMB231, HeLa and MG 63) than free CUR. However, such cytotoxicity was further enhanced by nearly ~8–10% using the folate receptor (FR)-based targeting. Furthermore, it demonstrated excellent antioxidant, as well as anti-inflammatory activity (NO assay) and such activity was found higher than that of free CUR. Both AgAuNPCS and AgAuNPCS-CUR also exhibited excellent cytocompatibility to human keratinocyte and erythrocyte cells. Hence, from the overall findings, we concluded that our biogenically synthesized AgAuNPCS alloy nanoparticle has, anti-inflammatory, anti-bacterial, anti-oxidant activity as well as potential for targeted therapy (in cancer) via controlled CUR delivery in biomedical applications.