Hello,

I think that the sonication step depends on the type of the nanoparticles you are measuring. For example: I do not suggest to sonicate liposomes, because they can be damaged. On the other hand I would recommend to sonicate all rigid particles before the analysis to get rid of the aggregates, which may have been created while the samples was stored or so. This will improve the polydispersity anmd I think that it will provide the "more realistic" information about the particle size.

Denisa Lizonova By definition, agglomerates (loosely bound) can be dispersed by sonication; aggregates (tightly chemically bound) cannot. If you're starting with a powder then it will be a laser diffraction experiment. With a sol/colloidal suspension then DLS is an option for particle size measurement.

I agree that the answer is 'it depends'. Emulsions are another class of materials that should not be sonicated.

It depends on your samples. The only way to answer your question is for you to make the measurements before and after sonication. If there is a difference, then you need to decide which is most appropriate for what you are trying to achieve/understand.

Thank you for your answered Denisa Lizonova , Alan F Rawle and John Francis Miller . I really appreciate. So, it's depend on what I want to achieve. I made comparison before and after sonication, there is significant different Z average values.

I'm studying for aggregation of my samples by concentration. Is it, z average of micelle should decreasing in size as compared to monomer?

Do you have any references that I could refer?

Thank you

Hi

I had some practical work on using sonication on nano-emulsion, it is remarkably destroyed the smaller of about 100 nm diameter. and it is useful in re-dispersion of nanoparticles.