Doping control for nandrolone using hair analysis.

Abstract

A sensitive, specific and reproducible method for the quantitative determination of nandrolone in human hair has been developed. The sample preparation involved a decontamination step of the hair with methylene chloride. The hair sample (about 100 mg) was solubilized in 1 ml NaOH IN, 15 min at 95 degrees C, in presence of 10 ng nandrolone-d(3) used as an internal standard. The homogenate was neutralized and extracted using consecutively a solid phase (Isolute C18) and a liquid--liquid (pentane) extraction. The residue was derivatized by adding 50 microl MSTFA/NH4I/2-mercaptoethanol (1000:2:5; v/v/v), then incubated for 20 min at 60 degrees C. A 4-microl aliquot of the derivatized extract was injected into the column (HP5-MS capillary column, 5% phenyl--95% methylsiloxane, 30 m x 0.25 mm i.d. x 0.25 mm film thickness) of a Hewlett Packard (Palo Alto, CA) gas chromatograph (6890 Series) via a Hewlett Packard (7673) autosampler. The assay was capable of detecting 0.5 pg of nandrolone per mg of hair when approximately 100 mg of hair were processed. Linearity was observed for nandrolone concentrations ranging from 1 to 50 pg/mg with a correlation coefficient of 0.997. Intra-day and between-day precisions at 10 pg/mg were 11.2 and 15.1%, respectively, with an extraction recovery of 81.7%. The analysis of three strands of hair, obtained from three bodybuilders, revealed the presence of nandrolone at the concentration of 1, 3.5 and 7.5 pg/mg.