Dear All,
Currently, I am doing some synthesis work in order to get control-size Au nanoparticles. I found the fantastic paper: <Seeding Growth for Size Control of 5-40 nm Diameter Gold Nanoparticles> published in Langmuir in 2001 written by Nikhil R. Jana, Latha Gearhear and Murphy.
I followed procedure of this paper to synthesis some Au nanoparticle.
Gold Seed Solution: aqueous solution (25mM HAuCl4 and 25mM trisodium citrate) + ice-cold, freshly prepared 0.1 M NaBH4
Growth Solution: 200ml aqueous solution of 25mM HAuCl4 + 6 CTAB
Formulation: 7.5 of growth solution + 0.05ml 0.1M ascorbic acid + 2.5ml Seed Solution
After stirring 10 min the solution become wine red.
However some problem occurred at the Thiol Capping and Subsequent Solvent Extraction part. In this paper, it writes several steps below:
--> 10 ul of dodecanethiol was added to 10 ml of particle solution and stirred for 1h
--> 20 mg of KI and 0.5 ml of toluene were added to the particles solution and shaken for 1-2 min.
results--> The upper toluene portion was red due to particle ext extraction and the water phase was colorless.
I follow the procedure like below:
--> 10 ul of dodecanethiol was added to 10 ml of particle solution and stirred for 2h
--> 20 mg of KI was added into the solution
--> 0.5 ml of toluene was then added to the particles solution and shaken for 1-2 min
results--> the solution became turbid after shaken 2 min. even after storage 24 hours, the upper toluene was still clear, and the down solution were still red. and there are a few white matter between water solution and toluene.
I just join this field two weeks, and i am lack of experience in this field. nobody in my group research this. so pls kindly help
me.
So many thanks for your opinion.
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Best Regards and Wishes
Makuna