EXTRACTION OF STEROIDS FROM ANIMAL SERUM/PLASMA
1. Mix 230 µl Serum/Plasma with 1 ml Diethylether.
2. Vortex thoroughly (2x20 Sec.).
3. Centrifuge 5 min. at 3800 x g, until the phases are completely separated.
4. Freeze the test tubes at –70° C, then decant the liquid organic supernatant (ether fraction).
5. Evaporate the extract at room temperature under a hood to ca. 100 µl ® Rinse the walls of the tube with 150 µl ether ® Vortex briefly.
6. Put the tube in an ultrasound unit for 10 minutes.
7. Evaporate the extract to ca. 20 µl.
8. Reconstitute the residue with 75 µl Steroid Free Human Serum (Zero Standard). Vortex briefly. Centrifuge 3 min. at 3800 x g.
6. This extract can be used in the DRG EnzymeImmunoassay as described under ‘Assay Procedure’.
Pls. note: For calculation of the sample results pls. divide the sample value with the appropriate correction factor (for the above described procedure the correction factor is 3.07).
Factor calculation 3.07 = 230µl / 75 µl