Solid-phase column chromatographic and gas chromatographic-mass spectrometric determination of heptaminol in human urine and related pharmacokinetic profiles.

Heptaminol is an antihypotensive drug and is one of the stimulants banned in sport competitions. When heptaminol was fortified to a drug-free urine sample and subjected to solid-phase extraction, trifluroacetic anhydride derivatization, and gas chromatography-mass spectrometry analysis, the results indicated three chromatographic peaks, with one major peak [peak 1 (P1) as heptaminol-2TFA], appearing at retention time 7.17 min, and two minor peaks [peak 2 (P2) and peak 3 (P3) as heptaminol-TFA], appearing at RT 5.87 and 5.81 min, respectively. The characteristic ions of peak mass spectra were m/z 322, 224, and 140 for P1, m/z 223 (molecular ion), 208, 140, and 110 for P2, and m/z 208, 140, and 110 for P3. The urine samples collected from healthy male volunteers who orally ingested a single dose (100 mg) of heptaminol were similar to the analytical results shown in the heptaminol-spiked control urine samples. This result suggested that the unchanged heptaminol was the sole form found in urine. The unchanged parent compound was completely eliminated in urine within 24 h and an average of approximately 97% of the dose was excreted through the renal pathway.

Metabolites of ephedrines in human urine after administration of a single therapeutic dose.

Ephedrine (EPH), pseudoephedrine (PEPH), phenylpropanolamine (PPA), methylephedrine (MEPH) and cathine are sympathomimetic amines. These drugs are commonly found in over-the-counter (OTC) cold medicines and some dietary supplements. In Taiwan, the misuse of these drugs has resulted in an increase in athletic violations. Excretion studies of the ephedrine-related drugs have been performed to better understand the metabolic yields of ephedrines in urine. After consuming a single clinical dose of each of these drugs, urine samples from volunteers (n=3 for each drug) were subjected to tert-butyl-methyl-ether (TBME) extraction and trifluoroacetic acid (TFAA) derivatization before gas chromatography-mass spectrometry (GC-MS) analysis. Most ephedrines were excreted unchanged in urine, including EPH (40.9%), PEPH (72.2%), and PPA (59.3%). However, only a relatively small amount of MEPH (15.5%) was excreted unchanged in urine. In addition, a trace amount of PPA (1.6%) and cathine (0.7%) was found to be the metabolites of EPH and PEPH, respectively. Urinary EPH, PEPH, and PPA reached peaks at 2-6h and disappeared in urine at approximately 24-48 h post-administration. For MEPH, the peaks of excretion extended from 4 to 12h post-administration and were undetectable at approximately 48 h. A single clinical dose of EPH (25 mg) may exceed threshold level (10 microg/mL) in sport drug testing if the urine samples are tested within approximately 8h post-administration. However, a single dose of MEPH (20 mg) never reached the threshold value (10 microg/mL).

Detection of modafinil in human urine by gas chromatography-mass spectrometry.

The main purpose of this study was to detect and quantify modafinil in human urine by gas chromatography-mass spectrometry (GC-MS). Urinary samples were collected from three healthy male volunteers following oral administration of a clinical dose (100 mg) of modafinil (Provigil). Urine specimens were extracted with t-butylmethyl ether (TBME) prior to GC-MS analysis. The results demonstrate that the chromatographic characteristics and the mass spectrum of the unchanged parent drug extracted from urine samples were identical to that obtained from the authentic standard. The times for the unchanged modafinil to reach peak concentration in the urine of the three volunteers were at 2 h (6.14 microg/mL), 4 h (9.93 microg/mL) and 8 h (3.58 microg/mL), respectively. Total clearance occurred in approximately 48-72 h with 2-5% eliminated through urine as unchanged modafinil. The present study demonstrates that modafinil is detectable in the absence of hydrolysis and derivatization steps.

Quantification and profiling of 19-norandrosterone and 19-noretiocholanolone in human urine after consumption of a nutritional supplement and norsteroids.

Nandrolone is one of the synthetic anabolic steroids banned in sports and has been a popular substance abused by athletes in recent years. One of its major metabolites, 19-norandrosterone (19-NA), has been used as a determinant for drug violations in sports. Current reports regarding nandrolone-positive cases have been related to intake of some nandrolone-free nutritional supplements. The aim of this study was to learn whether if a nutritional supplement sold by over-the-counter (OTC) nutritional stores could yield the same metabolic products as that of nandrolone. If so, what is (are) the substance(s) that contributed to the nandrolone metabolites? To determine the content of an OTC nutritional supplement, a tablet was dissolved in methanol, followed by N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA)-trimethyliodosilane (TMIS) derivatization prior to gas chromatography-mass spectrometry (GC-MS) analysis. The collected urine samples underwent extraction, enzymatic hydrolysis, and derivatization before the analyses of GC-MS. The results showed that seven anabolic steroids were found as contaminants in the nutritional supplement, in addition to six that were listed in the ingredients by the manufacturer. We confirmed previous reports that administration of the OTC supplement could produce a positive urine test for nandrolone metabolites. Furthermore, the results from excretion studies showed that 19-NA and 19-noretiocholanolone (19-NE) were present in urine after consuming the nutritional supplement, nandrolone, 19-nor-4-androsten-3,17-dione, 19-nor-4-androsten-3beta,17beta-diol, and 19-nor-5-androsten-3beta,17beta-diol. The 19-NA concentrations in urine were generally higher than that of 19-NE (19-NA/19-NE ratio > 1.0) especially during the early stage of excretion, that is, before 6 h post-administration. After this period of time, the concentrations of 19-NA and 19-NE fluctuated and might even have reversed (19-NA/19-NE ratio < 1.0) in their ratio, that is, higher yield in 19-NE than that in 19-NA. On the basis of this study, we postulate that some doping violations of nandrolone could be attributed by indiscriminate administration of the OTC nutritional supplements that contained 19-norsteroids.