High-performance liquid chromatographic separation and detection methods for anabolic compounds

Voltammetric investigation of diethylstilbestrol

In this work electrooxidation of diethylstilbestrol (DES) was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) using a glassy carbon (GC) electrode. It was statistically shown that both methods could be used for the determination of DES in the concentration range of 2 x 10(-5)-6 x 10(-4) M by CV and 1 x 10(-5)-1 x 10(-3) M in methanol (MeOH) and 4 x 10(-5)-6 x 10(-4) M in acetonitrile (ACN) by DPV and both of the methods could be applied to human serum. A mechanism was proposed about the electrooxidation of this substance.

Steroid metabolism by ovarian follicles of the sea bass Dicentrarchus labrax

Ovarian samples from fear sea bass, Dicentrarchus labrax, were collected for the in vitro incubations during the spawning period. Follicles with fully developed vitellogenic oocytes showing central germinal vesicle (stage I follicles) and follicles with oocytes showing initial germinal vesicle migration (stage II follicles) were treated with either (1) 20 microg sea bass hypophysis plus 50 ng 17-hydroxyprogesterone (17-P), (2) 20 microg hypophysis alone, (3) 50 ng 17-P alone and (4) media alone. Structure-activity experiments used stage II follicles treated with several dosages (0.1, 1.0 and 10.0 ng/ml) of either 17-P, 17,20beta-P, or 17,20beta,21-P. Free and conjugated (sulfates and glucuronides) levels of the established teleost oocyte maturation inducing steroids (MIS), i.e. 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P) and 17,20beta,21-trihydroxy-4-pregnen-3-one (17,20beta,21-P) were measured in the incubation media by high performance liquid chromatography. Our results show that the synthesis of free and conjugated 17,20beta-P is constant (0.1-0.2 ng/ml) in all incubates. In contrast, the synthesis of free and conjugated 17,20beta,21-P is higher in incubates containing stage II follicles (up to 5 ng/ml) than in those having stage I follicles (up to 3 ng/ml; P<0.01). Structure-activity data reveal that 17-P is not effective at inducing in vitro germinal vesicle breakdown whereas both 17,20beta-P and 17,20beta,21-P are equally potent and highly effective. These results demonstrate that 17,20beta-P and 17,20beta,21-P are synthesized in vitro by follicles of sea bass and that sulfation is the main route for the metabolism of the C(21)-steroids in riper follicles. The highest levels of 17,20beta,21-P, found in incubates containing stage II follicles, points at 17,20beta,21-P, rather than 17,20beta-P, as the most probable MIS in sea bass, nonetheless, this hypothesis requires further confirmation.

Multi-residue analysis of anabolics in calf urine using high-performance liquid chromatography with diode-array detection

We describe the development of an HPLC method with diode-array detection (DAD) for the analysis and identification of 20 substances with anabolic properties, that are considered as potential growth promoters, to be used for the analysis of extracts of calf urine samples. The substances are separated on an RP-Select B column using a mobile phase consisting of a mixture of acetonitrile and water. Gradient elution from 43-76% acetonitrile in water with a concave curve was used to achieve a good separation of the compounds with an acceptable analysis time. For the identification, a retention parameter and the UV spectrum were used. The retention parameter was the retention time corrected with a reference mixture. The latter reduced the standard deviations to about 25% of their original values. The limits of detection of the HPLC system ranged from 0.5-5 ng injected amount for the androgens, progestagens, stilbenes and resorcylic acid lactones and to 5-10 ng injected amount for the oestrogens. After extraction from urine the limits of detection were increased by the presence of matrix components, but they were between 5 and 10 ng injected amount for most of the substances.

Natural sex steroids and their xenobiotic analogs in animal production: growth, carcass quality, pharmacokinetics, metabolism, mode of action, residues, methods, and epidemiology

Natural and xenobiotic compounds having sex-related actions have long been used for growth promotion and various changes in carcass quality in meat animals. The first compounds used were synthetic estrogens; however, later on a whole battery of compounds having androgenic, and progestogenic actions have also been involved. In surveying the effects of these compounds in meat-producing animals, it became clear that these drugs increase the growth rate of the treated animals and bring about changes in the carcass that are generally characterized by lower fat content and more lean mass. Extensive studies undertaken in various countries, including the European Economic Community (EEC), have shown that if used according to good husbandry practices, the meat from treated animals does not have excessive amounts of residues compared with the endogenous amount of steroid production in the animals in question and also in human beings. The banning of these compounds in the European community brought a new phenomenon of illegal or black market cocktails. These mixtures of anabolic steroids are injected into the body of the animals rather than implanted in the ears, which is the normal practice in countries where they have not yet been banned. Several screening and confirmatory methods are now available for monitoring programs. However, these programs need excessive resources in terms of manpower, funds, and proper legislation, which in underdeveloped countries is questionable, particularly in the absence of strong scientific evidence for the exercise.

Use of high-performance liquid chromatography-diode array detection in forensic toxicology

A comprehensive approach to the analysis for many drugs in postmortem blood and biological fluids using high-performance liquid chromatography and diode array detection has been developed. To reduce the likelihood of co-eluting interference components of postmortem blood or other drugs, selective back-extraction was also used to screen and quantitate drugs in blood and biofluids. An isocratic mobile phase (acetonitrile, phosphoric acid and triethylamine buffer, pH 3.4) was developed and found stable, reliable and convenient for general drug screening and quantitation. A library of drug spectra in the ultraviolet wavelength range (210-367 nm) was established for 272 drugs on two reversed-phase columns: Supelcosil (biphenyl) and LiChrospher RP-8. The application of several methods to whole blood, the analysis of complex cases and the use of multicomponent analysis for qualitative and quantitative analysis is discussed.

Identification and verification of the anabolic steroid boldenone in equine blood and urine by HPLC/ELISA

An enzyme linked immunosorbent assay (ELISA) was developed to detect the anabolic steroid boldenone in equine blood and urine. The polyclonal antiserum was raised in rabbits, employing boldenone-17-hemisuccinate-bovine serum albumin as antigen. Boldenone-17-hemisuccinate-horseradish peroxidase served as enzyme conjugate. Sensitivity of the assay was 26.0 +/- 3.0 pg/well. Among the endogenous steroids tested only progesterone and testosterone exhibited moderate cross-reactivities, 3.4 and 2.5%, respectively. These cross-reactivities are of no importance for the boldenone assay. For the reduction of background levels, screening for boldenone of equine serum was performed after extraction. Urine samples were determined directly after dilution, omitting hydrolysis of boldenone conjugates. Positive screening results were confirmed by means of two independent HPLC systems combined with off-line detection, employing the boldenone ELISA. Methandienone served as internal standard to ascertain retention factors. In horses treated with boldenone-17-undecylenate the presence of boldenone in serum was confirmed up to 28 days and in unhydrolyzed urine up to 56 days post applicationem.