How do you perform extractions on an oil sample?

To pretreat an oil sample, you can first dilute the sample with at least 5 parts of hexane to break up the sample matrix.  If analytes of interest are lipophilic, the diluted oil sample can be loaded directly onto a normal phase SPE cartridge for sample cleanup.  Examples of normal phase cartridges are Strata EPH, Strata Florisil, Strata Amino, Strata Cyano and Strata Silica.

If analytes of interest are hydrophilic, a liquid extraction can be performed using water or acidified water.  The water layer can then undergo further cleanup by reversed phase solid phase extraction.