▎ 摘　　要

In this study, the gold nanoparticles-doped graphene oxide (AuNPs/GO) was prepared via a biosynthesis path using the Mangifera indica leaf extract. The characterization of produced AuNPs/GO was thoroughly conducted by modern methods such as X-ray diffraction, Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, zeta potential, and so on. The analyses showed that spherical AuNPs were uniformly distributed on the GO sheets with an average diameter of 11-21 nm, proving the successful formation of AuNPs/GO nanocomposite. The initial effects of HAuCl4 volume, reaction time, pH level, the presence of 24-hour-prolonged GO, the amount of GO, and the experiment order were carried out to find the most suitable synthesis conditions and enhance the overall performance of AuNPs/GO. The results indicated that the most appropriate conditions for the fabrication process include 5 mL of extract, 1500 mL of HAuCl4, a reaction time of 120 s, at pH 7,1500 mL of 24-hour-prolonged GO, and the experiment sequence of adding HAuCl(4 )to the remaining precursors. The nanocomposite was also discovered to effectively inhibit the growth of both Pseudomonas aeruginosa and Staphylococcus aureus bacteria strains, indicating nearly 100% of bactericidal rates at 50 mg/mL. Meanwhile, the catalytic reduction activity of organic dyes by NaBH(4 )using the AuNPs/GO support, tested with methylene blue, methyl orange, malachite green, and crystal violet dyes, was also excellent in terms of relatively high efficiency of 99.83, 93.81, 99.85, and 97.93%, respectively. Along with remarkable recovery and reusability confirmed, those results show the highly promising applications of AuNPs/GO in the antiseptics field and treatment of dye-contaminated water sources. (C) 2022 Elsevier Ltd. All rights reserved.