Direct Immersion Sampling

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Direct immersion sampling with SPME simplifies extraction of polar analytes that are extremely soluble in many sample matrices. Begin the extraction process by placing the sample into the vial puck on the hotplate. Insert the holder into the sampling stand; passing the needle through the septum that seals the sample vial. Position the fiber below the surface of the liquid and start the timer. The SPME immersion sampling concentrates the dissolved organics on the fiber coating through agitation and heating of the sample. After completion of the extraction with the SPME fiber, retract the fiber into the protective needle and remove it from the sample vial. Inject the SPME needle into the heated GC injection port. Push the plunger down, exposing the fiber to the heat of the injection port and thermally desorbing the collected analyte into the GC column for analysis.