Hello
I have prepared metal nanoparticles and did zeta potential. Normally there is a single peak in sample but now there are 3 peaks.
I prepared sample for analysis first I prepared 10 mg/mL stock solution, sonicated sample then prepared 1 mg/mL dilution from stock sonicated again. Then I filtered sample and sent for the analysis.
What should I do so I get a single peak?
Have you compared with ready-made cards for the material to be prepared?
Noor Ul Ain
Water molecules are connected by hydrogen bonds. In addition, they form large-sized thermal fluctuations and small-sized quantum fluctuations due to the nuclear quantum effect. When you apply sonication (pressure) to an aqueous dispersion, quantum fluctuations become more stable and their diffusion appears more clearly in the form of “particles”. That's why you see three peaks: metal nanoparticles, thermal and quantum fluctuation. To confirm this effect, measure the peak of the water. Then treat it with ultrasound and compare. When sonicating, even in clean water, peaks should appear. To avoid peaks, grind the particles to obtain a smaller size.
Yuri Mirgorod thank you for detailed guidance. I do grind my sample before making the dilutions. But I analyzed it two times and in both double or triple peaks appeared.
Should I not sonicate my samples before analysis? I do it to make a homogenous suspension of nanoparticles.
Noor Ul Ain
Try not to sonicate before analysis. Be sure to report the result of the analysis.