Analyze Diet

Topic:Doping

Doping in horses refers to the administration of prohibited substances or methods to enhance performance or alter behavior during competitions. This practice is a concern in equestrian sports due to its potential impact on animal welfare, fair play, and the integrity of the sport. Substances used in doping can range from stimulants and painkillers to sedatives and anti-inflammatory drugs. Detection methods include blood and urine tests, designed to identify the presence of banned substances or their metabolites. This page compiles peer-reviewed research studies and scholarly articles that explore the detection methods, regulatory frameworks, and ethical considerations associated with doping in equine sports.
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.
Analytica chimica acta    June 10, 2013   Volume 787 163-172 doi: 10.1016/j.aca.2013.05.058
Gray BP, Viljanto M, Bright J, Pearce C, Maynard S.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 myo-inositol tris pyrophosphate (ITPP) in equine following an administration of ITPP.
Drug testing and analysis    June 4, 2013   Volume 6, Issue 3 268-276 doi: 10.1002/dta.1473
Lam G, Zhao S, Sandhu J, Yi R, Loganathan D, Morrissey B.Myo-Inositol tris pyrophosphate (ITPP) is a powerful allosteric modulator of haemoglobin that increases oxygen-releasing capacity of red blood cells. It is capable of crossing the red blood cell membrane unlike its open polyphosphate analog myo-inositol hexakisphosphate (IHP). Systemic administration of ITPP enhanced the exercise capacity in mice. There have been rumours of its abuse in the horse racing industry to enhance the performance of racing horses. In this paper, the detection of ITPP in equine plasma and urine after an administration of ITPP is reported. A Standardbred mare was admini...
Fast and sensitive analysis of dermorphin and HYP6-dermorphin in equine plasma using liquid chromatography tandem mass spectrometry.
Drug testing and analysis    May 29, 2013   Volume 6, Issue 4 342-349 doi: 10.1002/dta.1487
Wang CC, Hartmann-Fischbach P, Krueger TR, Wells TL, Feineman AR, Compton JC.Dermorphin and HYP(6) -dermorphin are hepta-peptides and natural opioids originally isolated from the skin of South American frogs. They are more potent than morphine but less likely to produce drug tolerance and addiction. These properties make them ideal candidates for the doping of racehorses to enhance performance during competition. Dermorphin was recently classified as a Class I drug by Racing Commissioners International (RCI), indicating that it is a banned substance in equine athletes. To enforce this ban, a fast and sensitive method was developed for dermorphin and HYP(6)-dermorphin a...
Identification of α-cobratoxin in equine plasma by LC-MS/MS for doping control.
Analytical chemistry    April 30, 2013   Volume 85, Issue 10 5219-5225 doi: 10.1021/ac4006342
Bailly-Chouriberry L, Cormant F, Garcia P, Kind A, Popot MA, Bonnaire Y.Cobra venom (Naja kaouthia) contains a toxin called ฮฑ-cobratoxin (ฮฑ-Cbtx). This toxin is a natural protein containing 71 amino acids (MW 7821 Da) with a reported analgesic potency greater than morphine. In 2007, in USA, this substance was found in the barns of a thoroughbred trainer and since then till date, the lack of a detection of this molecule has remained a recurring problem for the horseracing industry worldwide. To solve this problem, the first method for the detection of ฮฑ-cobratoxin in equine plasma has now been developed. Plasma sample (3 mL) was treated with ammonium sulfate at ...
Detection, quantification, and identification of dermorphin in equine plasma and urine by LC-MS/MS for doping control.
Analytical and bioanalytical chemistry    April 10, 2013   Volume 405, Issue 14 4707-4717 doi: 10.1007/s00216-013-6907-0
Guan F, Uboh CE, Soma LR, Robinson M, Maylin GA, Li X.Dermorphin is a unique opioid peptide that is 30-40 times more potent than morphine. It was misused and went undetected in horse racing until 2011 when intelligence obtained from a few North American race tracks suggested its use. To prevent such misuse, a reliable analytical method became necessary for detection and identification of dermorphin in post-race horse samples. This paper describes the first liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for such a purpose. Equine plasma and urine samples were pre-treated with ethylenediamine tetra-acetic acid and urea prior to so...
[Doping].
Tijdschrift voor diergeneeskunde    March 6, 2013   Volume 138, Issue 2 81 
Boissevain I.No abstract available
Ultra high performance liquid chromatography/tandem mass spectrometry based identification of steroid esters in serum and plasma: an efficient strategy to detect natural steroids abuse in breeding and racing animals.
Journal of chromatography. A    February 10, 2013   Volume 1284 126-140 doi: 10.1016/j.chroma.2013.02.010
Kaabia Z, Dervilly-Pinel G, Hanganu F, Cesbron N, Bichon E, Popot MA, Bonnaire Y, Le Bizec B.During last decades, the use of natural steroids in racing and food producing animals for doping purposes has been flourishing. The endogenous or exogenous origin of these naturally occurring steroids has since remained a challenge for the different anti-doping laboratories. The administration of these substances to animals is usually made through an intra-muscular pathway with the steroid under its ester form for a higher bioavailability and a longer lasting effect. Detecting these steroid esters would provide an unequivocal proof of an exogenous administration of the considered naturally occ...
Metabolic studies of formestane in horses.
Drug testing and analysis    January 21, 2013   Volume 5, Issue 6 412-419 doi: 10.1002/dta.1444
Leung GN, Kwok WH, Wan TS, Lam KK, Schiff PJ.Formestane (4-hydroxyandrost-4-ene-3,17-dione) is an irreversible steroidal aromatase inhibitor with reported abuse in human sports. In 2011, our laboratory identified the presence of formestane in a horse urine sample from an overseas jurisdiction. This was the first reported case of formestane in a racehorse. The metabolism of formestane in humans has been reported previously; however, little is known about its metabolic fate in horses. This paper describes the in vitro and in vivo metabolic studies of formestane in horses, with the objective of identifying the target metabolite with the lon...
Doping control analysis of seven bioactive peptides in horse plasma by liquid chromatography-mass spectrometry.
Analytical and bioanalytical chemistry    January 15, 2013   Volume 405, Issue 8 2595-2606 doi: 10.1007/s00216-012-6697-9
Kwok WH, Ho EN, Lau MY, Leung GN, Wong AS, Wan TS.In recent years, there has been an ongoing focus for both human and equine doping control laboratories on developing detection methods to control the misuse of peptide therapeutics. Immunoaffinity purification is a common extraction method to isolate peptides from biological matrices and obtain sufficient detectability in subsequent instrumental analysis. However, monoclonal or polyclonal antibodies for immunoaffinity purification may not be commercially available, and even if available, such antibodies are usually very costly. In our study, a simple mixed-mode anion exchange solid-phase extra...
Validated UHPLC-MS-MS method for rapid analysis of capsaicin and dihydrocapsaicin in equine plasma for doping control.
Journal of analytical toxicology    January 11, 2013   Volume 37, Issue 2 122-132 doi: 10.1093/jat/bks098
You Y, Uboh CE, Soma LR, Guan F, Taylor D, Li X, Liu Y, Chen J.A method involving ultra high-performance liquid chromatography-tandem mass spectrometry was developed and validated for the analysis of capsaicin and dihydrocapsaicin in equine plasma. The analytes were recovered from plasma by liquid-liquid extraction using methyl tert-butyl ether and separated on a sub-2 micron column. The mobile phase was composed of 2 mM ammonium formate and methanol. A triple quadrupole mass spectrometer was used to detect the analytes in positive electrospray ionization mode with selected reaction monitoring. The limits of detection, quantification and confirmation for ...
Identification of recombinant human relaxin-2 in equine plasma by liquid chromatography-high resolution mass spectrometry.
Drug testing and analysis    October 18, 2012   Volume 5, Issue 8 627-633 doi: 10.1002/dta.1427
Kwok WH, Ho EN, Leung GN, Wong AS, Yue SK, Wan TS.Relaxin (RLX) is a peptide hormone belonging to the relaxin-like peptide family. Relaxin-2 (RLX-2), a heteromeric polypeptide consisting of an A-chain (24 amino acids) and a B-chain (29 amino acids) linked together by two inter-chain disulfide bonds, is the main circulating RLX hormone in human. Due to its ability to dilate blood vessels surrounding the smooth muscles via induction of nitric oxide resulting in the increase of blood and oxygen supplies to the muscles, it may enhance athletic performance and is therefore banned in horseracing, equestrian competitions, and human sports. In order ...
Individual identification of racehorses from urine samples using a 26-plex single-nucleotide polymorphism assay.
Journal of forensic sciences    October 12, 2012   Volume 58, Issue 1 21-28 doi: 10.1111/j.1556-4029.2012.02291.x
Kakoi H, Kijima-Suda I, Gawahara H, Kinoshita K, Tozaki T, Hirota K, Yoshizawa M.To construct a system for identifying individual horses from urine samples that are submitted for postracing doping tests, we developed a genotyping assay based on 26-plex single-nucleotide polymorphisms (SNPs). DNA was isolated from urine using a commercially available DNA/RNA extraction kit, and SNP genotyping was achieved with a SNaPshot(โ„ข) technique. DNA profiles including 26 SNPs were acquired from urine samples and blood/hair samples. Within the studied Thoroughbred population, the 26-plex assay showed a probability of identity of 5.80 ร— 10(-11). Compared to the conventional short tan...
Doping control analysis of TB-500, a synthetic version of an active region of thymosin ฮฒโ‚„, in equine urine and plasma by liquid chromatography-mass spectrometry.
Journal of chromatography. A    September 23, 2012   Volume 1265 57-69 doi: 10.1016/j.chroma.2012.09.043
Ho EN, Kwok WH, Lau MY, Wong AS, Wan TS, Lam KK, Schiff PJ, Stewart BD.A veterinary preparation known as TB-500 and containing a synthetic version of the naturally occurring peptide LKKTETQ has emerged. The peptide segment (17)LKKTETQ(23) is the active site within the protein thymosin ฮฒ(4) responsible for actin binding, cell migration and wound healing. The key ingredient of TB-500 is the peptide LKKTETQ with artificial acetylation of the N-terminus. TB-500 is claimed to promote endothelial cell differentiation, angiogenesis in dermal tissues, keratinocyte migration, collagen deposition and decrease inflammation. In order to control the misuse of TB-500 in equin...
Detection of peginesatide in equine serum using liquid chromatography-tandem mass spectrometry for doping control purposes.
European journal of mass spectrometry (Chichester, England)    September 14, 2012   Volume 18, Issue 4 407-412 doi: 10.1255/ejms.1189
Mรถller I, Thomas A, Wingender A, Machnik M, Schรคnzer W, Thevis M.Erythropoietin (EPO) and its recombinant analogues are suspected to be illicitly administered to horses for performance enhancing purposes and, consequently, prohibited in equine sports. Recently, a new erythropoiesis-stimulating agent, peginesatide (Omontys, formerly referred to as Hematide), belonging to the upcoming class of EPO-mimetic peptides, received approval for the treatment of anaemia in humans with chronic kidney disease on dialysis. As the pegylated dimeric peptide of approximately 45 kDa without sequence homology to EPO is not detectable by conventional EPO detection assays, spec...
High resolution accurate mass screening of prohibited substances in equine plasma using liquid chromatography–Orbitrap mass spectrometry.
Drug testing and analysis    September 3, 2012   Volume 5, Issue 7 509-528 doi: 10.1002/dta.1395
Ho EN, Kwok WH, Wong AS, Wan TS.A recent trend in the use of high resolution accurate mass screening (HRAMS) for doping control testing in both human and animal sports has emerged due to significant improvement in high resolution mass spectrometry in terms of sensitivity, mass accuracy, mass resolution, and mass stability. A number of HRAMS methods have been reported for the detection of multi-drug residues in human or equine urine. As blood has become a common matrix for doping control analysis, especially in equine sports, a sensitive, fast and wide coverage screening method for detecting a large number of drugs in equine ...
Metabolic studies of 1-testosterone in horses.
Drug testing and analysis    June 20, 2012   Volume 5, Issue 2 81-88 doi: 10.1002/dta.1380
Kwok WH, Ho EN, Leung GN, Tang FP, Wan TS, Wong HN, Yeung JH.1-Testosterone (17ฮฒ-hydroxy-5ฮฑ-androst-1-en-3-one), a synthetic anabolic steroid, has been described as one of the most effective muscle-building supplements currently on the market. It has an anabolic potency of 200 as compared to 26 for testosterone. Apart from its abuse in human sports, it can also be a doping agent in racehorses. Metabolic studies on 1-testosterone have only been reported for human in the early seventies, whereas little is known about its metabolic fate in horses. This paper describes the studies of in vitro and in vivo metabolism of 1-testosterone in horses, with the ai...
Structural elucidation of phase I and II metabolites of bupivacaine in horse urine and fungi of the Cunninghamella species using liquid chromatography/multi-stage mass spectrometry.
Rapid communications in mass spectrometry : RCM    May 5, 2012   Volume 26, Issue 11 1338-1346 doi: 10.1002/rcm.6225
Rydevik A, Bondesson U, Hedeland M.Bupivacaine is a local anaesthetic prohibited in equine sports. It is highly metabolized in the horse but a thorough description of its metabolite profile is lacking. An administration study should find appropriate analytical targets for doping control. Furthermore, knowledge of an in vitro system for production of metabolites would be beneficial. Methods: Marcainยฎ (bupivacaine hydrochloride) was administered subcutaneously to a horse and urine samples were collected. In vitro metabolic systems consisting of the fungi Cunninghamella elegans and Cunninghamella blakesleeana were incubated with ...
Acepromazine pharmacokinetics: a forensic perspective.
Veterinary journal (London, England : 1997)    April 23, 2012   Volume 194, Issue 1 48-54 doi: 10.1016/j.tvjl.2012.03.017
Schneiders FI, Noble GK, Boston RC, Dunstan AJ, Sillence MN, McKinney AR.Acepromazine (ACP) is a useful therapeutic drug, but is a prohibited substance in competition horses. The illicit use of ACP is difficult to detect due to its rapid metabolism, so this study investigated the ACP metabolite 2-(1-hydroxyethyl)promazine sulphoxide (HEPS) as a potential forensic marker. Acepromazine maleate, equivalent to 30mg of ACP, was given IV to 12 racing-bred geldings. Blood and urine were collected for 7days post-administration and analysed for ACP and HEPS by liquid chromatography-mass spectrometry (LC-MS). Acepromazine was quantifiable in plasma for up to 3h with little r...
Detection of recombinant human EPO administered to horses using MAIIA lateral flow isoform test.
Analytical and bioanalytical chemistry    April 18, 2012   Volume 403, Issue 6 1619-1628 doi: 10.1007/s00216-012-5972-0
Lรถnnberg M, Bondesson U, Cormant F, Garcia P, Bonnaire Y, Carlsson J, Popot MA, Rollborn N, Rรฅsbo K, Bailly-Chouriberry L.Doping of horses with recombinant human erythropoietin (rHuEPO) to illegally enhance their endurance capacity in horseracing has been reported during the last years. This leads to increased blood viscosity which can result in sudden death and is of concern for the horse welfare. Additionally, the horse can start production of rHuEPO antibodies, which cross-reacts with endogenous equine EPO and can lead to severe anaemia and even death. In this study, a novel micro-chromatographic method, EPO WGA MAIIA, has been tested for the capability in plasma and urine samples to detect administration of e...
A new analytical method based on anti-EPO monolith column and LC-FAIMS-MS/MS for the detection of rHuEPOs in horse plasma and urine samples.
The Analyst    March 27, 2012   Volume 137, Issue 10 2445-2453 doi: 10.1039/c2an15662h
Bailly-Chouriberry L, Cormant F, Garcia P, Lรถnnberg M, Szwandt S, Bondesson U, Popot MA, Bonnaire Y.Recombinant human erythropoietin (rHuEPO) is a 30-34 kDa glycoprotein banned by the racing authorities. For some years this molecule has been detected in race horses in USA and in Europe, and even in racing camels. Although direct methods to differentiate horse endogenous EPO and rHuEPO have been developed either by LC-MS/MS or by isoelectric focusing (IEF) with double-blotting, the short confirmation time of such prohibited hormone in plasma remains a problem for horseracing doping control laboratories. In order to improve the rHuEPOs confirmation process in horse plasma or urine in terms of ...
Detection of myo-inositol trispyrophosphate in equine urine and plasma by hydrophillic interaction chromatography-tandem mass spectrometry.
Drug testing and analysis    February 22, 2012   Volume 4, Issue 5 355-361 doi: 10.1002/dta.397
Wong AS, Ho EN, Wan TS.Myo-inositol trispyrophosphate (ITPP) is a new drug capable of increasing the amount of oxygen in hypoxic tissues. Studies have shown that administration of ITPP increases the maximal exercise capacity in normal mice as well as mice with severe heart failure. The properties of ITPP make it an ideal candidate as a doping agent to enhance performance in racehorses. While there have been speculations in the horseracing industry that the covert use of ITPP is already widespread, no reported method exists for the detection of ITPP in equine biological samples. ITPP is a difficult-to-detect drug due...
Rapid screening of anabolic steroids in horse urine with ultra-high-performance liquid chromatography/tandem mass spectrometry after chemical derivatisation.
Journal of chromatography. A    January 10, 2012   Volume 1232 257-265 doi: 10.1016/j.chroma.2011.12.095
Wong CH, Leung DK, Tang FP, Wong JK, Yu NH, Wan TS.Liquid chromatography/mass spectrometry (LC/MS) has been successfully applied to the detection of anabolic steroids in biological samples. However, the sensitive detection of saturated hydroxysteroids, such as androstanediols, by electrospray ionisation (ESI) is difficult because of their poor ability to ionise. In view of this, chemical derivatisation has been used to enhance the detection sensitivity of hydroxysteroids by LC/MS. This paper describes the development of a sensitive ultra-high-performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) method for the screening of a...
Detection of singly- and doubly-charged quaternary ammonium drugs in equine urine by liquid chromatography/tandem mass spectrometry.
Analytica chimica acta    November 2, 2011   Volume 710 94-101 doi: 10.1016/j.aca.2011.10.046
Ho EN, Kwok WH, Wong AS, Wan TS.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...
Horse metabolism and the photocatalytic process as a tool to identify metabolic products formed from dopant substances: the case of sildenafil.
Drug testing and analysis    October 1, 2011   Volume 3, Issue 10 724-734 doi: 10.1002/dta.334
Medana C, Calza P, Giancotti V, Dal Bello F, Pasello E, Montana M, Baiocchi C.Two horses were treated with sildenafil, and its metabolic products were sought in both urine and plasma samples. Prior to this, a simulative laboratory study had been done using a photocatalytic process, to identify all possible main and secondary transformation products, in a clean matrix; these were then sought in the biological samples. The transformation of sildenafil and the formation of intermediate products were evaluated adopting titanium dioxide as photocatalyst. Several products were formed and characterized using the HPLC/HRMS(n) technique. The main intermediates identified in thes...
Liquid chromatography electrospray ionization tandem mass spectrometry for the detection of mesocarb abuse in horse doping.
Drug testing and analysis    October 1, 2011   Volume 3, Issue 10 717-723 doi: 10.1002/dta.345
Appolonova SA, Baranov PA, Mesonzhnik NV, Brazhnikova DO, Rodchenkov GM.A method is described for the determination of mesocarb abuse in equestrian sport by combining gradient liquid chromatography and electrospray ionization tandem mass spectrometry. Mesocarb was administrated orally to two horses at a dose of 50 ยตg/kg. Urine samples were collected up to 120โ€‰h post administration. Hydrolyzed and conjugated urine fractions were handled using liquid-liquid extraction (LLE). The identity of the parent drug and metabolites was confirmed using liquid chromatography combined with tandem mass spectrometry (MS/MS). Mesocarb and seven metabolites were detected in horse...
In vitro metabolism of tiletamine, zolazepam and nonbenzodiazepine sedatives: Identification of target metabolites for equine doping control.
Drug testing and analysis    September 14, 2011   Volume 3, Issue 10 705-716 doi: 10.1002/dta.300
Fenwick SJ, Scarth JP.Within horseracing, the detection of prohibited substance doping often requires urine analysis; hence, it is necessary to understand the metabolism of the drugs in question. Here, the previously unknown equine metabolism of eight sedatives is reported in order to provide information on target metabolites for use in doping control. Phase I metabolite information was provided by incubation with equine liver S9 fraction. In vitro techniques were chosen in order to reduce the ethical and financial issues surrounding the study of so many compounds, none of which are licensed for use in horses in th...
Detection of various performance enhancing substances in specimens collected from race horses in Illinois: a five-year experience.
Journal of analytical toxicology    August 30, 2011   Volume 35, Issue 7 438-443 doi: 10.1093/anatox/35.7.438
Taddei L, Benoit M, Sukta A, Peterson J, Gaensslen RE, Negrusz A.In order to protect the integrity of horse racing in Illinois, a complex testing of urine and blood specimens collected post-race from winning and special designation horses is continuously conducted. The initial screening by immunoassays was followed by the confirmation on presumptive positive samples. Instrumental screening was also conducted. Perimortem and postmortem specimens and special exhibits (syringes, needles, etc.) were also analyzed. The administration of alkalinizing agents was detected by measuring the total plasma carbon dioxide concentration. The laboratory analyzed specimens ...
Efficient use of retention time for the analysis of 302 drugs in equine plasma by liquid chromatography-MS/MS with scheduled multiple reaction monitoring and instant library searching for doping control.
Analytical chemistry    August 12, 2011   Volume 83, Issue 17 6834-6841 doi: 10.1021/ac2016163
Liu Y, Uboh CE, Soma LR, Li X, Guan F, You Y, Chen JW.Multiple drug target analysis (MDTA) used in doping control is more efficient than single drug target analysis (SDTA). The number of drugs with the potential for abuse is so extensive that full coverage is not possible with SDTA. To address this problem, a liquid chromatography tandem mass spectrometric method was developed for simultaneous analysis of 302 drugs using a scheduled multiple reaction monitoring (s-MRM) algorithm. With a known retention time of an analyte, the s-MRM algorithm monitors each MRM transition only around its expected retention time. Analytes were recovered from plasma ...
Comparison of different liquid chromatography stationary phases in LC-HRMS metabolomics for the detection of recombinant growth hormone doping control.
Journal of separation science    June 27, 2011   Volume 34, Issue 24 3493-3501 doi: 10.1002/jssc.201100223
Boyard-Kieken F, Dervilly-Pinel G, Garcia P, Paris AC, Popot MA, le Bizec B, Bonnaire Y.Growth hormone (GH) is a polypeptide suspected of being used in horse racing to speed up physical performances. Despite scientific advances in the recent years, the control of its administration remains difficult. In order to improve it, a metabolomics study through LC-high resolution mass spectrometry measurements was recently initiated to assess the metabolic perturbations caused by recombinant equine growth hormone administration. Few tens of ions not identified structurally were highlighted as compounds responsible for the modification of metabolic profiling observed in treated animals. Th...
Simultaneous separation and determination of 16 testosterone and nandrolone esters in equine plasma using ultra high performance liquid chromatography-tandem mass spectrometry for doping control.
Journal of chromatography. A    May 6, 2011   Volume 1218, Issue 26 3982-3993 doi: 10.1016/j.chroma.2011.04.087
You Y, Uboh CE, Soma LR, Guan F, Li X, Liu Y, Rudy JA, Chen J, Tsang D.The potential for using testosterone and nandrolone esters in racehorses to boost the biological concentrations of these steroids and enhance athletic performance is very compelling and should be seriously considered in formulating regulatory policies for doping control. In order to regulate the use of these esters in racehorses, a sensitive and validated method is needed. In this paper, we report such a method for simultaneous separation, screening, quantification and confirmation of 16 testosterone and nandrolone esters in equine plasma by ultra high performance liquid chromatography-tandem ...
1 9 10 11 12 13 19