Chromatography Forum

Hello Guys

We are looking to develop an extraction method for soil and sediment samples based on ultrasonication. I'd appreciate any suggestions as to what brands or specifications to look out for. Any suggestions related to the method are also welcome.

Thanks

Hello Guys

We are looking to develop an extraction method for soil and sediment samples based on ultrasonication. ........... Any suggestions related to the method are also welcome.

Thanks

I would suggest not re-inventing the wheel - a literature search will throw up dozens, maybe hundreds of ultrasound assisted extractions.

Peter

We recently tested a classical ultrasound device for soil samples and I have to say that may not be the best method to extract things from soil: soil particles are heavy and tend to agglomerate at the bottom of the tube. I think motion based extraction tools are more appropriate. In the end we used a vertical rotation agitator overnight and it worked fine.

Agree with Gaetan. We've used a rotator for soil and sludge samples rather than ultrasonication. Do take the time to test the extraction - some things extract within 15 minutes, some things need to go overnight.

Agree with both Gaetan and MMJ88. For soil we use a rotating extractor, following the general USEPA method 3570, which employs a 4 hour rotation timeframe.

Interestingly, by switching to this method we have had some issues with our performance evaluation (PT) standards. Turns out the statistics are weighted low because so many people use ultrasonication and get low recoveries. We typically get 70-120% for spiked analytes, which occasionally throws us off the top end of the "acceptable recovery" range for PT samples.