Synthesis of monodisperse gold nanoparticles stabilized by gemini surfactant in reverse micelles

Gold nanoparticles were prepared by the reduction of HAuCl4 using NaBH4 as reducing agent in a water-in-oil reverse micelles system, in which gemini surfactant 2-hydroxy-1, 3-bis ( octadecyldimethylammonium) propane dibromide (18-3( OH)-18) was used as stabilizer. The results of TEM and AFM show that the gold nanoparticles have a narrow size distribution. The UV-vis absorption spectra reveal that the gemini surfactant 18-3(OH)-18 can stabilize the gold nanoparticles for at least two months.