Salting out supported liquid extraction

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Analytica Chimica Acta (ACA) has published a novel analytical method which combines extraction and clean-up in a single step. The so-called salting out supported liquid extraction (SOSLE) follows the liquid-liquid extraction principles, its main advantage being the capability of extracting compounds of a wide polarity range (1). The technique was evaluated using the multi-residue quantification of veterinary drugs in milk as model analytical problem.

Acetonitrile was selected as extractant and the immiscibility with the aqueous sample is achieved by using a high concentration of ammonium sulfate, thus permitting the supported liquid-liquid extraction (SLE) using a polar organic solvent. The benefits of SLE technique has been recognized  by Ronald E. Majors, editor of "Sample Preparation Perspectives" in LC/GC journal, who defined it as the best kept secret in sample preparation (2). The approach presented in ACA by our colleagues from Zurich overcomes the limitation of conventional SLE related with the need of non-polar organic phases which makes difficult the applicability of the technique to multi-residue determination.

From Microextraction Tech, we invite our followers to go through this article and check the excellent results obtained for more than one-hundred veterinary products. The SOSLE methodology is quite versatile as it can be adapted to a given analytical problem by the proper selection of the salt-extractant binomial. the use of high resolution mass-spectrometric detection is also an added value of this work.

References:
(1) Multi-residue quantification of veterinary drugs in milk with a novel extraction and cleanup technique: Salting out supported liquid extraction (SOSLE).Link to the article
(2) Supported Liquid Extraction: The Best-Kept Secret in Sample Preparation. Link to the article

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