New Sample Preparation Methodology to Enable Higher Recovery and Minimize Loss of Difficult Analytes in Food and Natural Products by LC/MS or GC/MS

The most critical aspects of reliable food contamination analysis are the reduction of interferences from the sample matrix and analyte recovery. Traditionally, Solid Phase Extraction (SPE), Supported Liquid Extraction (SLE), liquid-liquid, syringe filtration, and centrifugation have been used to reduce matrix interference prior to LC/MS analysis. However, these techniques are time consuming, adversely impact recovery, require expensive consumables, and use large amounts of solvent which then need to be concentrated. Several studies comparing these techniques to Thomson eXtreme® Filter Vials for contaminant analysis were conducted in orange juice, soil, milk, shellfish and water.

SPE, SLE, liquid-liquid, syringe filtration and centrifugation are common sample preparation techniques prior to GC or LC analysis of pesticides in food and natural products. Typically, these techniques are used to concentrate analytes and to reduce interference from co-eluting compounds. These techniques are also commonly used to clean-up/filter particulates following the extraction of particulate laden samples. Drawbacks to the use of these techniques include cost, sample preparation time, use and disposal of organic solvents, and in some instances, poor recoveries due to incomplete extraction of the liquid layer, loss of analytes during wash steps, or analytes remaining bound to packing materials.