Analytica chimica acta.
Publisher:
Elsevier. Amsterdam : Elsevier
Frequency: Fifty no. a year, 2002-
Country: Netherlands
Language: English
Start Year:1947 -
ISSN:
0003-2670 (Print)
1873-4324 (Electronic)
0003-2670 (Linking)
1873-4324 (Electronic)
0003-2670 (Linking)
Impact Factor
6.2
2022
| NLM ID: | 0370534 |
| (DNLM): | A29820000(s) |
| (OCoLC): | 01716731 |
| Coden: | ACACAM |
| Classification: | W1 AN191L |
Comprehensive solid-phase extraction of multitudinous bioactive peptides from equine plasma and urine for doping detection. The ability to analyze biological samples for multitudinous exogenous peptides with a single analytical method is desired for doping control in horse racing. The key to achieving this goal is the capability of extracting all target peptides from the sample matrix. In the present study, theory of mixed-mode solid-phase extraction (SPE) of peptides from plasma is described, and a generic mixed-mode SPE procedure has been developed for recovering multitudinous exogenous peptides with remarkable sequence diversity, from equine plasma and urine in a single procedure. Both the theory and the develop...
Metabolic studies of oxyguno in horses. Oxyguno (4-chloro-17α-methyl-17β-hydroxy-androst-4-ene-3,11-dione) is a synthetic oral anabolic androgenic steroid commercially available without a prescription. Manufacturers of oxyguno claim that its anabolic effect in metabolic enhancement exceeds that of the classic anabolic steroid testosterone by seven times, but its androgenic side-effects are only twelve percent of testosterone. Like other anabolic androgenic steroids, oxyguno is prohibited in equine sports. The metabolism of oxyguno in either human or horse has not been reported and therefore little is known about its metabolic fate...
Investigations into the feasibility of routine ultra high performance liquid chromatography-tandem mass spectrometry analysis of equine hair samples for detecting the misuse of anabolic steroids, anabolic steroid esters and related compounds. The detection of the abuse of anabolic steroids in equine sport is complicated by the endogenous nature of some of the abused steroids, such as testosterone and nandrolone. These steroids are commonly administered as intramuscular injections of esterified forms of the steroid, which prolongs their effects and improves bioavailability over oral dosing. The successful detection of an intact anabolic steroid ester therefore provides unequivocal proof of an illegal administration, as esterified forms are not found endogenously. Detection of intact anabolic steroid esters is possible in plasma samp...
Detection of singly- and doubly-charged quaternary ammonium drugs in equine urine by liquid chromatography/tandem mass spectrometry. Quaternary ammonium drugs (QADs) are anticholinergic agents some of which are known to have been abused or misused in equine sports. A recent review of literature shows that the screening methods reported thus far for QADs mainly cover singly-charged QADs. Doubly-charged QADs are extremely polar substances which are difficult to be extracted and poorly retained on reversed-phase columns. It would be ideal if a comprehensive method can be developed which can detect both singly- and doubly-charged QADs. This paper describes an efficient liquid chromatography/tandem mass spectrometry (LC/MS/MS) m...
A broad-spectrum equine urine screening method for free and enzyme-hydrolysed conjugated drugs with ultra performance liquid chromatography/tandem mass spectrometry. The authors' laboratory at one time employed four liquid chromatography/mass spectrometric (LC/MS) methods for the detection of a large variety of drugs in equine urine. Drug classes covered by these methods included anti-diabetics, anti-ulcers, cyclooxygenase-2 (COX-2) inhibitors, sedatives, corticosteroids, anabolic steroids, sulfur diuretics, xanthines, etc. With the objective to reduce labour and instrumental workload, a new ultra performance liquid chromatography/tandem mass spectrometric (UPLC/MS/MS) method has been developed, which encompasses all target analytes detected by the origina...
Influence of magnetic field on aqueous two-phase extraction of horse ferritin in the polyethylene glycol/hydroxyethyl starch system. The presented experiments show the model of expectation of equine spleen ferritin extraction in a new aqueous two-phase system which was formed by mixing polyethylene glycol (PEG) and hydroxyethyl starch (HES). The tendency of the protein to migrate in the analyzed systems was dependent on the concentrations of HES and PEG as well as PEG molecular weight. The highest concentration of ferritin in the top phase (rich in PEG) was recorded in the system composed of 6% PEG 3000 and 3% HES. The obtained concentration was 0.88 mg mL(-1). The lowest concentration was 0.42 mg mL(-1) in the system compo...
Use of benchtop exactive high resolution and high mass accuracy orbitrap mass spectrometer for screening in horse doping control. Liquid chromatography-mass spectrometry (LC-MS) has been widely used in doping control laboratories over the last two decades. Currently, simple quadrupole, triple quadrupole and ion trap are the most commonly employed analyzers in toxicological analysis. Nevertheless, the main lack of these technologies is the restricted number of target compounds simultaneously screened without loss of sensitivity. In this article we present an innovative screening approach routinely applied in the French horse doping control laboratory based on high resolution (50000) and high mass accuracy (<5 ppm) in f...
Determination of non-steroidal anti-inflammatory drugs residues in animal muscles by liquid chromatography-tandem mass spectrometry. A confirmatory method for the determination of residues of nine non-steroidal anti-inflammatory drugs and one metabolite in animal muscles has been developed. After enzymatic hydrolysis samples were extracted with acetonitrile and cleaned up using alumina and C(18) SPE cartridges. Liquid chromatography-tandem mass spectrometry was used for the separation and determination of analytes. The method was validated in bovine muscles, according to the Commission Decision 2002/657/EC criteria. Applicability of the method in the analysis of swine, horse and chicken muscles was checked by precision and ...
Aminorex and rexamino as metabolites of levamisole in the horse. Administration studies of levamisole in horses were carried out using two different levamisole preparations, namely, levamisole hydrochloride oral bolus and levamisole phosphate injectable solution. These preparations were analysed in detail for the presence of aminorex-like impurities. Both levamisole preparations were found to contain 1-(2-mercaptoethyl)-4-phenyl-2-imidazolidinone (I) and 4-phenyl-2-imidazolidinone (II) as degradation impurities, but neither aminorex nor rexamino was detected in these preparations. After the administration of these preparations to horses, aminorex, rexamino,...
Metabolic studies of mesterolone in horses. Mesterolone (1alpha-methyl-5alpha-androstan-17beta-ol-3-one) is a synthetic anabolic androgenic steroid (AAS) with reported abuses in human sports. As for other AAS, mesterolone is also a potential doping agent in equine sports. Metabolic studies on mesterolone have been reported for humans, whereas little is known about its metabolic fate in horses. This paper describes the studies of both the in vitro and in vivo metabolism of mesterolone in racehorses with an objective to identify the most appropriate target metabolites for detecting mesterolone administration. In vitro biotransformation st...
Studies related to the origin of C18 neutral steroids isolated from extracts of urine from the male horse: the identification of urinary 19-oic acids and their decarboxylation to produce estr-4-en-17beta-ol-3-one (19-nortestosterone) and estr-4-ene-3,17-dione (19-norandrost-4-ene-3,17-dione) during sample processing. For almost two decades we have known that enzymatic hydrolysis of "normal" urine samples from the entire male horse using Escherichia coli (E. coli) followed by solvolysis (ethyl acetate:methanol:sulphuric acid) results in the detection of significant amounts of estr-4-ene-3,17-dione (19-norandrost-4-ene-3,17-dione) along with estr-4-en-17beta-ol-3-one (19-nortestosterone, nandrolone) in extracts of the hydrolysed urine and that both steroids are isolated from the solvolysis fraction. This solvolysis process is targeted at the steroid sulphates. Also we have shown that 19-norandrost-4-ene-3,17...
Metabolic studies of turinabol in horses. Turinabol (4-chloro-17alpha-methyl-17beta-hydroxy-1,4-androstadien-3-one) is a synthetic oral anabolic androgenic steroid. As in the case of other anabolic steroids, it is a prohibited substance in equine sports. The metabolism of turinabol in human has been reported previously; however, little is known about its metabolic fate in horses. This paper describes the studies of both the in vitro and in vivo metabolism of turinabol in racehorses with an objective to identify the most appropriate target metabolites for detecting turinabol administration. For the in vitro studies, turinabol was incub...
Quantitation of 17beta-nandrolone metabolites in boar and horse urine by gas chromatography-mass spectrometry. A method to quantify metabolites of 17beta-nandrolone (17betaN) in boar and horse urine has been optimized and validated. Metabolites excreted in free form were extracted at pH 9.5 with tert-butylmethylether. The aqueous phases were applied to Sep Pak C18 cartridges and conjugated steroids were eluted with methanol. After evaporation to dryness, either enzymatic hydrolysis with beta-glucuronidase from Escherichia coli or solvolysis with a mixture of ethylacetate:methanol:concentrated sulphuric acid were applied to the extract. Deconjugated steroids were then extracted at alkaline pH with tert-...
A stereochemical examination of the equine metabolism of 17alpha-methyltestosterone. An investigation was conducted into the stereochemistry of the equine urinary metabolites of 17alpha-methyltestosterone observed after oral administration. Standards of the complete range of C3/C5/C16 stereoisomeric 17alpha-methylandrostane-3,17beta-diols, 17alpha-methylandrostane-3,16,17beta-triols and 17alpha-hydroxymethylandrostane-3,17beta-diols were purchased or synthesised, and were used to unequivocally identify the absolute structures of the metabolites. Phase I metabolism was found to involve combinations of Delta(4)-3-ketone reduction with both 5alpha,3beta- and 5beta,3alpha-stereoch...