[Extraction of urinary pregnanediol and estriol by the Bio-Rad column]

In the present study, we have evaluated the quality control parameters of a new method for the determination of the urinary Pregnandiol and Estriol using a small column AG 1X2 proposed by Bio-Rad Laboratories. The principle of this method is based on a single extraction of steroids by ion exchange and methanol elution under different pH conditions. Compared to the "classical" methods using solvent extraction, the present method has some advantages mainly the elimination of the use of large volumes of solvents and the reduction of the sample volume to be analyzed. The preliminary results showed a recovery of 89,0% - 98,9% (C.V. = 5%) for Estriol and 83,8% - 93, 2% C.V = 5%) for Pregnandiol . The precision of the method evaluated by its repeatability and between-assay reproductibility showed 4% and 6% variation for Estriol and Pregnandiol . The Comparison of the present method with a classical one using Ether/Ethanol (4/1) for extraction gave us a very good correlation.