Hello everyone.
I am performing a top-down synthesis of micro and nanoparticles and one of the final steps requires ultrasonication in order to achieve the desired particle size. During my experiments I have observed that the sonication power of the ultrasonic bath is not the same everywhere, which limits the reproducibility of the proces depending on where I place the flask with my sample (especially during microparticle synthesis).
I was wondering if anyone had the same issue and managed to solve it. I am thinking of using a stainless steel mesh suport in order to try to create controlled regions in the bath with high vibrational efficiency thanks to the reflection of the ultrasonic waves.
Are there any other ideas?
Hi Gerard
you are right! I think there are no obvious and general solutions. You should check where the ultrasonication is more efficient and put the vial in this position. Usually, in an ultrasonic bath the best position is in the middle of the bath, but to my personal experience it depends. Then you should try by changing the shape of the container. Usually, flasks are the best.
Dear Gerard,
I'm not sure but there were experimental studies on these problems, homogeneous ultrasonic field in a cylindrical chamber in 198 ... in Hungary. Studies, not solution! Do not waste your time looking for them.
I do not believe that the stainless steel net will help you.
I will advise you:
Try to work with a rotating or eccentric container. You can also try sloping bottom container. If you have time try to define the optimum speed i.e. the revolutions.
Cheers
Thankyoy very much Franco and Jack for your answers.
I tried once some bizarre setup in which the vials where rotating excentrically. It improved a little bit the performance of the sonication. The problem I had was that it was bulky and it was quite difficult to hold the vials in place (some times they fell from the rotating axis). So I abandoned that solution. Probably this solution required a better setup than the one I did and I would need some time to define the optimum rpm range.
Since I am running out of time, I think I will try to identify the regions where the ultrasonication is more efficient and try to maintain them in that position.
Thankyou again to both of you for your advice!!
Best regards
Can you use a probe-type ultrasonicator instead of a bath? Switching to probe sonication has given me more reproducible results, and decreased the duration required.
Ia m agree with D Wehrung, but maybe incresing the frequency the quality annd homogeneity shoulb be better,
Dear @Daniel and @Francisco,
Thankyou for your answers. It is good to know that probe sonication gives better results. I will check if it is possible to get access to one of these probes and do some trials.
Regarding the increase of the frequency, it resulted in better sonication quality but still some inhomogeneity in the bath could be appreciated. Also the resulting microparticles seemed smaller. Maybe this solution could work, but since the bath heats also faster I will have to check that this higher frequency does not affect the composition of the particles.
Thankyou again for your answers.
Best regards
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanostructured Materials
- Nanoparticles