Synthesis and Properties of Ag‐Au Alloy Nanoparticles with Controlled Composition for Computed Tomography Imaging Applications

Abstract Numerous non‐invasive assays have been developed to support CT imaging, consequently increasing the precision of diagnosis. Although these efforts made a significant contribution to clinical research, there is still more to be done. The goal is to replace conventional contrast agents with more potent ones. In this study, Ag−Au alloy nanoparticles were fabricated by substitution method between the precursor Au³⁺ and the previously prepared Ag nanoparticles. Effects of Au³⁺ quantity on the formation and characteristics of Ag−Au alloy nanoparticles were investigated. It showed that Ag−Au nanoalloy with a size of 14.2±1.0 nm, SPR absorption peak at 520 nm, and Ag: Au atomic ratio of approximately 3 : 1 were appropriate for biomedical applications. After phase transfer using poly (maleic anhydride‐alt‐1‐octadecene) (PMAO), the nano Ag−Au solution owned remarkable durability, stability and non‐toxicity Vero healthy cell line at high test concentration. In‐vitro CT imaging demonstrated a good X‐ray adsorption coefficient, and the hounsfield units (HU) was noticeably increased. As a promising CT contrast agent, the X‐ray attenuation of nano Ag−Au solutions correlated linearly with concentrations. These findings led to a potential application in the biomedical field, particularly in computed tomography (CT) imaging diagnosis.