Journal of Analytical Toxicology, Vol. 14, March/April 1990 Analysis of Anabolic Steroids Using GCIMS with Selected Ion Monitoring BongChul Chung, Hea-Young P. Choo, TaeWook K/m, KheeDong Eom, OhSeung Kwon, Jawon Suh, Jongsoon Yang, and Jongsei Park* Doping Control Center, Korea Institute of Science & Technology, P.O. Box 131, Cheongryang, Seou/, Korea analyze the steroids either qualitatively or quantitatively (10-23). Abstract ] Anabolic steroids are extensively metabolized: hydroxylation, reduction, oxidation, and conjugation are common metabolic This study describes the use of gas chromatography/mass pathways of anabolic steroids in humans. As far as conjugation spectrometry with selected ion monitoring to screen 18 patterns are concerned, steroids can be divided into two groups, anabolic steroids banned by the International Olympic nonconjugated (free) steroid and conjugated steroid. Donike Committee. These anabolic steroids are analyzed in two reported that methandienone, oxandrolone, fluoxymesterone, fractions depending on their excretion pattern: stanozolol, dehydrochlormethyltestosterone, and formyldieno- nonconjugated (free) or conjugated fraction. The wet lone can be detected somewhat easily in the nonconjugated frac- procedure of extracting steroids from urine consists of an Initial isolation of lipophilic compounds on a column packed tion. These anabolic steroids have a 17/3-hydroxy-17tx-methyl with Amberllte XAD-2 resin, followed by enzymatic group in their structure (Figure 1). The other anabolic steroids hydrolysis with/J-glucuronidase from Escherichis co//. After whose structures are shown in Figure 2 are excreted mainly extraction, the hydrolyzed steroids are derivatized to the as glucuronides. corresponding trimethylsllyl ethers. The derivatized steroids ere analyzed by gas chromatography/mass spectrometry with selected ion monitoring of their characteristic ions. It takes 12 and 26 min to run GC/MS and edit the raw data for Materials nonconjugated and conjugated fractions respectively. Reagents. Amberlite XAD-2 resin, 150-200 #m, from Serva was used. Methanol (500 mL) was distilled at 64~ the first Introduction 50 mL was discarded and the next 300 mL was collected. The In 1974, steroids were added to the list of doping agents phosphate buffer, pH 7.0, was 250 mL of 0.2M K2HPO, mixed banned by the International Olympic Committee on the grounds with 50 mL of 0.2M KH2PO,. Diethylether was distilled with that drug abuse is against the Olympic spirit based on fair play, calcium hydride and stored in a refrigerator at ca. l~ and also it is known that steroid abuse will harm the well-being curonidase from Escherichia coli was from Boeringer. N-methyl- of athletes. Nevertheless, it is suspected that the use of steroids N-trimethylsilyl trifluoroacetamide (MSTFA), trimethyliodosil- ane (TMSI), and trimethylchlorosilane (TMSCI) were from has been steadily increasing among the players, who believe that the use of steroids improves their physical strength remarkably Sigma, and N-methyl-N-trimethylsilyl heptafluorobutyramide (MSHFB) and N-methyl-bisheptafluorobutyramidewere from over a short period of time and who are willing to barter their health for fame and monetary gain. Precise and rapid deter- Macherey-Nagel. mination of anabolic steroids and their metabolites continues Instrumentation. Analyses were performed with a Hewlett- to be of interest. Packard Model 5890A gas chromatograph and Model 5970B Some steroids can be analyzed with high-performance liquid mass selective detector. chromatography (HPLC) (1-5), and it has been possible to detect GC/MS operating conditions for nonconjugated fraction. A 17a-methyl, 17a-ethyl, and 19-nortestosterone steroids by cross-linked 5O/o phenylmethylsiliconecapillary column (length radioimmunoassay (RIA) despite the method's low specificity 17 m, i.d. 0.2 mm, film thickness 0.33/~m) was connected into (6-9). However, both of these methods cannot provide the data the ion source. Samples were injected in the splitless mode. necessary to confirm a presumptive positive sample. Therefore, Temperatures of injector and transfer line were set at 300~ gas chromatography/mass spectrometry (GC/MS) with high Oven temperature was initially 180~ ramped by 25~ to sensitivity and specificity has been regarded as the most reliable 300~ and held for 3 min. The carrier gas was helium at a flow technique so far. In many cases, GC/MS has been used to rate of 0.7 mL/min (at 180~ GC/MS operating conditions for conjugated fraction. The GC was equipped with a 17-m HP-1 fused-silica capillary column, 9Author to whom correspondence should be addressed. 0.2 mm i.d., 0.11-/zm film thickness. The oven temperature was Reproduction (photocopying) of editorial content of this journal is prohibited without publisher's permission, 91 Journal of Analytical Toxicology,Vol. 14, March/April 1990 programmed from 180~ to 224~ at a rate of 4~ and Enzymatic hydrolysis and derivaUzationof conjugated steroid then to 300~ at a rate of 15~ The carrier gas was To the phosphate buffer layer, 25 #L of ~-glucuronidase were hydrogen with a flow rate of 1.2 mL/min (at 180~ The split added and the mixture was heated at 55~ for 1 h. After cooling, ratio was 1:10. Mass spectral confirmation was performed on 1,2-dideuterotestosterone (10 ppm, 20 #L), internal standard a Hewlett-Packard Model 5988A GC/MS system. for conjugated steroid analysis, 100 mg of K2CO3, and 5 mL of diethylether were added. After 30 seconds of shaking in a vortex-mixer, 1 g of anhydrous sodium sulfate was added under continuous vortex- Experimental (see Scheme 1) mixing. After 10 min at room temperature, the tubes were cen- trifuged at 2500 rpm. The ethereal phase was transferred to Preparation of XAD-2 column another centrifuge tube and was concentrated by use of a A 3-mm diameter glass ball was introduced in the pasteur vacuum rotary evaporator. Before subjecting the residue to the pipette. The XAD-2 slurry was washed with acetone, methanol, derivatization procedure it was dried in a desiccator over and distilled water and was filled into the column until a bed P20,-KOH for 30 min. of 25-mm height was achieved. A final washing with 2 mL of To the dried residue, 50 #L of MSTFA-TMSI (1000:2) con- distilled water was carried out before applying the urine. taining 2 mg/mL of dithioerythritol was added and the tubes were heated at 60~ for 15 min. To derivatize the hydroxyl Isolation and derivatization of the nonconjugatedsteroids groups only, 50 ttL of MSTFA-TMSCI (100:2) was added and Urine (5 mE) and the internal standard, stanozolol (2 ppm, heated at 60~ for 3 min. 25/LL), were applied to the column. The XAD-2 column was washed with the same volume of water. The lipophilic adsorbed fraction containing both the free and conjugated steroids was eluted with 2.7 mL of distilled methanol applied in 0.9-mL frac- OH tions. The methanolic extract was brought to dryness with a vacuum rotary evaporator. The dried residues were redissolved in 1 mL of 0.2M phosphate buffer (pH 7.0) and 5 mL of ether. After shaking for 5 min and centrifugation at 2500 rpm for 5 min, two layers were separated. The phosphate buffer layer was cloetebol oxymesterone subjected to enzymatic hydrolysis. The ether layer was dried with a rotating evaporator, and the residue was dried in a vacuum desiccator over P~O,-KOH for at least 30 min. The residue was treated with 35 #L of the reagent mixture MSTFA-TMS-CI-TMS-imidazole(100:5:2, v/v/v) and heated to 80~ for 5 min. Then 5/zL of MBHFB was added and the oJ mesterolone boldenone solution was heated for an additional l0 min. OH OH Me methenolone oxymetholone O~ Me methondienone oxondronone oS oS nandrolone testosterone O~ Me OH OH o~ cH3 o~~.~ CH3 fluoxymesferone stanozolol HO~Me methyltestosterone bolasterone CI dehydrochloromethyl- formyidienolone testosterone norethondrolone dromostanolone Figure 1. Structuresof anabolic steroids in the free fraction. Figure 2. Structuresof anabolic steroids in the conjugatedfraction. 92 Journal of Analytical Toxicology, Vol. 14, March/April 1990 Results and Discussion Table I. SIM Characteristic Ions and Retention Times of Derivatized Main Metabolites of Anabolic Steroids Screening step (Free Fraction) Steroids were administered to volunteers and their urine was RRT Selected analyzed to determine the presence of metabolites of banned Steroid Metab01ite Derivative (rain) ions (re~z) steroids. In most cases, more than one metabolite was found Fluoxymesterone 6-0H-Flu0xy- 6,11,17-tris- 0.799 143, 642 in the urine samples collected during 5-20 h after ingestion. In mester0ne O-TMS,3-en01- 522, 462 some cases, such as oxymesterone, the parent steroid is the most TMS abundant in GC profiles. To optimize the steroid screening pro- Methandien0ne 6-0H-Methan- 6,17-bis-0-TMS 0.885 143, 209 cedure, the method was designed so that the major metabolites dienone 281, 460 or parent steroids and one or two other metabolites would be Oxandrolone 17-O-TMS 0,915 143, 309 321,363 detected. In addition, 2-3 characteristic ions for each metabolite Stanozolol 3'-OH-epista-N-HFB-3',17- 0,947 143, 669 were selected on the basis of their mass fragmentation. The nozolol bis-O-TMS 684 relative retention times of the chosen metabolites and the (3'-OH-Stano- N-HFB-3',17- 1,085 634, 378 selected ions are listed in Table I (free fraction) and Table 11 zolol) bis-O-TMS (conjugated fraction). IS (stanozolol) N-HFB-O-TMS 1,000 143, 581 596 Also, as shown in Table 1, most anabolic steroids in the free Oral-turinabol 6-OH-0ral 6,17-bis-O-TMS 1,042 143, 315 fraction are metabolized via 6-hydroxylation and all of these turinabol 317, 243 metabolites have the m/z 143 ion in their mass spectra.
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