Naphthazarin, a simple model of important antitumor agents in a facile size-tunable synthesis of gold nanoparticles

Abstract

2,3-Dihydro-5,8-dihydroxynaphthalene-1,4-dione (naphthazarin) (2) is used for the first time as a biologically important reagent in the synthesis of gold nanoparticles in water–methanol medium through the chemical reduction of HAuCl4 at room temperature without using any capping agents other than naphthazarin. The ratio of HAuCl4 and naphthazarin played a vital role in controlling the shape and size of gold nanoparticles. Three samples with significant differences in sizes (range of 10–200 nm) have been prepared through increasing the initial naphthazarin/HAuCl4 molar ratio from 50 to 200. The size, distribution, and formation of gold nanoparticles were confirmed by transmission electron microscopy, Fourier transform infrared spectroscopy, and UV–Visible absorption spectroscopic measurements. 2,3-Dihydro-5,8-dihydroxynaphthalene-1,4-dione (naphthazarin) as a green reagent is introduced for the first time in the synthesis of gold nanoparticles in water–methanol medium through chemical reduction of AuCl4 − by a suitable molar ratio of this reagent to HAuCl4 at room temperature without using any capping agents other than naphthazarin. The ratio of HAuCl4 and naphthazarin played a vital role in controlling the shape and size of gold nanoparticles. The size, distribution, and formation of gold nanoparticles were confirmed by transmission electron microscopy and Fourier transform infrared spectroscopy.