Analyze Diet

Topic:Chromatography

Chromatography is an analytical technique used to separate, identify, and quantify components within a mixture. In equine research, chromatography is applied to study various biological samples, such as blood, urine, and tissue, to investigate the metabolic and physiological processes in horses. This technique is instrumental in detecting and analyzing compounds like hormones, drugs, and nutrients, providing insights into equine health and performance. Different types of chromatography, including gas chromatography (GC) and high-performance liquid chromatography (HPLC), are utilized to achieve precise and reliable results. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, methodologies, and findings of chromatography in equine science.
Hydrophilic interaction chromatography of intact, soluble proteins.
Journal of chromatography. A    September 17, 2010   Volume 1218, Issue 35 5892-5896 doi: 10.1016/j.chroma.2010.09.027
Tetaz T, Detzner S, Friedlein A, Molitor B, Mary JL.The separation of intact proteins by means of Hydrophilic Interaction Chromatography (HILIC) was demonstrated with human apoA-I, recombinant human apoM, and equine cytochrome C. Five different commercially available HILIC columns were compared. Using one of these columns, different glycosylated isoforms of apoM were separated from each other and from the aglyco-form.
Identification of Rhodococcus equi lipids recognized by host cytotoxic T lymphocytes.
Microbiology (Reading, England)    March 18, 2010   Volume 156, Issue Pt 6 1836-1847 doi: 10.1099/mic.0.035915-0
Harris SP, Fujiwara N, Mealey RH, Alperin DC, Naka T, Goda R, Hines SA.Immune adult horses have CD8(+) cytotoxic T lymphocytes (CTLs) that recognize and lyse Rhodococcus equi-infected cells in an equine lymphocyte alloantigen (ELA)-A [classical major histocompatibility complex (MHC) class I]-unrestricted fashion. As protein antigens are MHC class I-restricted, the lack of restriction suggests that the bacterial antigens being recognized by the host are not proteins. The goals of this study were to test the hypothesis that these CTLs recognize unique R. equi cell-wall lipids related to mycobacterial lipids. Initial experiments showed that treatment of soluble R. e...
Purification and partial characterization of proteinase inhibitors of equine seminal plasma.
Reproductive biology    September 8, 2009   Volume 9, Issue 2 151-160 doi: 10.1016/s1642-431x(12)60023-0
Vasconcelos AB, Santos AM, Oliveira JS, Lagares Mde A, Santoro MM.The aims of the study were: 1/ to isolate and identify equine seminal plasma proteinase inhibitors, 2/ to evaluate their inhibitory potential, and 3/ to test a correlation between protein concentration in seminal plasma supernatant (obtained after precipitation with 36% ammonium sulfate) and stallion sexual maturity. Seminal plasma proteins obtained from six stallions were chromatographed in a Superose 12 (FPLC system) column followed by C(18) HPLC reverse-phase. Inhibition of trypsin amidase activity was evaluated in the collected fractions. Active proteins with a molecular mass of 6.3-7.0 KD...
Method for co-purification of equine neutrophil elastase and myeloperoxidase from a limited blood volume.
Research in veterinary science    May 5, 2009   Volume 87, Issue 3 358-363 doi: 10.1016/j.rvsc.2009.04.002
de la Rebière de Pouyade G, Serteyn D, Deby-Dupont G, Franck T.Neutrophil myeloperoxidase (MPO) and elastase can be released in severe inflammatory diseases and cause tissue injuries. Equine enzymes have already been individually purified from large blood quantities. We describe the isolation of both enzymes from a same limited blood volume. Both MPO and elastase were extracted by crushing PMN isolated by centrifugation on a percoll-gradient from a 460 ml blood collection. MPO and elastase were separated by an ionic exchange chromatography phase and further purified by gel filtration chromatography on Superdex 200 and 75, respectively. Enzymes were identi...
Effects of compounding and storage conditions on stability of pergolide mesylate.
Journal of the American Veterinary Medical Association    February 13, 2009   Volume 234, Issue 3 385-389 doi: 10.2460/javma.234.3.385
Davis JL, Kirk LM, Davidson GS, Papich MG.To determine the effects of temperature and light over a 35-day period on stability of pergolide mesylate after compounding in an aqueous vehicle. Methods: Evaluation study. Methods: Pergolide was compounded into a formulation with a final target concentration of 1 mg/mL. Aliquots of the formulation were then stored at -20 degrees, 8 degrees, 25 degrees, or 37 degrees C without exposure to light or at 25 degrees C with exposure to light for 35 days. Samples were assayed in triplicate by means of high-pressure liquid chromatography immediately after compounding and after 1, 7, 14, 21, and 35 da...
Plasma concentrations of testosterone and 19-nortestosterone (nandrolone) in the nonracing intact male horse by liquid chromatography-mass spectrometry.
Journal of veterinary pharmacology and therapeutics    November 13, 2008   Volume 31, Issue 6 587-590 doi: 10.1111/j.1365-2885.2008.00997.x
Soma LR, Uboh CE, Guan F, McDonnell S.No abstract available
Evaluation of adult equine bone marrow- and adipose-derived progenitor cell chondrogenesis in hydrogel cultures.
Journal of orthopaedic research : official publication of the Orthopaedic Research Society    October 26, 2007   Volume 26, Issue 3 322-331 doi: 10.1002/jor.20508
Kisiday JD, Kopesky PW, Evans CH, Grodzinsky AJ, McIlwraith CW, Frisbie DD.Bone marrow mesenchymal stem cells (BM-MSCs) and adipose-derived progenitor cells (ADPCs) are potential alternatives to autologous chondrocytes for cartilage resurfacing strategies. In this study, the chondrogenic potentials of these cell types were compared by quantifying neo-tissue synthesis and assaying gene expression and accumulation of extracellular matrix (ECM) components of cartilage. Adult equine progenitor cells encapsulated in agarose or self-assembling peptide hydrogels were cultured in the presence or absence of TGFbeta1 for 3 weeks. In BM-MSCs-seeded hydrogels, TGFbeta1 stimulate...
A simplified method of determining synovial fluid chondroitin sulfate chain length.
Osteoarthritis and cartilage    July 16, 2007   Volume 15, Issue 12 1443-1445 doi: 10.1016/j.joca.2007.05.018
Brown MP, Trumble TN, Sandy JD, Merritt KA.To determine whether dimethylmethylene blue (DMMB) analysis, when combined with agarose gel filtration chromatography (Superose 6), can be performed instead of fluorophore-assisted carbohydrate electrophoresis (FACE) to determine chondroitin sulfate (CS) chain length in synovial fluid (SF). Methods: SF was obtained from (1) normal horses after 8 weeks of rest, (2) the same horses after 9 months of treadmill training, and (3) horses with osteochondral (OC) injury from racing. SF CS concentrations and chain lengths were determined by gel chromatography and DMMB analysis and compared with previou...
Exercise and injury increase chondroitin sulfate chain length and decrease hyaluronan chain length in synovial fluid.
Osteoarthritis and cartilage    May 31, 2007   Volume 15, Issue 11 1318-1325 doi: 10.1016/j.joca.2007.04.005
Brown MP, Trumble TN, Plaas AH, Sandy JD, Romano M, Hernandez J, Merritt KA.(1) To investigate the effects of exercise and osteochondral (OC) injury on synovial fluid (SF) chondroitin sulfate (CS) and hyaluronan (HA) concentration and chain length, (2) to compare SF and cartilage CS data from joints with OC fragmentation, and (3) to compare SF CS and HA profiles with those seen in serum from the same horses. Methods: Serum and SF were obtained from (1) normal horses after 8 weeks rest, (2) the same horses after 9 months treadmill training, and (3) horses with OC injury from racing. Articular cartilage was also collected from group 3 horses. Concentrations and chain le...
LC-MS/MS method for confirmation of recombinant human erythropoietin and darbepoetin alpha in equine plasma.
Analytical chemistry    May 15, 2007   Volume 79, Issue 12 4627-4635 doi: 10.1021/ac070135o
Guan F, Uboh CE, Soma LR, Birks E, Chen J, Mitchell J, You Y, Rudy J, Xu F, Li X, Mbuy G.Recombinant human erythropoietin (rhEPO) and darbepoetin alpha (DPO) are protein-based drugs for the treatment of anemia by stimulating red blood cell production. Consequently, they are abused in human and equine sports. To deter their abuse in the horse racing industry, a sensitive and reliable method for confirmation of these agents in equine plasma has been in urgent need. Such a method by LC-MS/MS is described in this paper. The method involved analyte enrichment by immunoaffinity separation using anti-rhEPO antibody linked to magnetic beads, digestion by trypsin, and analysis by LC-MS/MS....
Reliability of 1,9-dimethylmethylene blue tests in comparison to agarose gel electrophoresis for quantification of urinary glycosaminoglycans.
Clinica chimica acta; international journal of clinical chemistry    December 14, 2006   Volume 378, Issue 1-2 206-215 doi: 10.1016/j.cca.2006.11.025
de Lima CR, Baccarin RY, Michelacci YM.The relevance of glycosaminoglycan determination in biological fluids is gradually gaining importance in the literature. Nevertheless, the results obtained by different methods vary widely. We evaluated 1,9-dimethylmethylene blue (DMB) dye-binding assays for quantification of urinary glycosaminoglycans, in comparison to densitometry after agarose gel electrophoresis. Methods: Urinary glycosaminoglycans from different mammalian species were quantified by 3 different DMB dye-binding assays. The results were compared to those obtained by densitometry after agarose gel electrophoresis of glycosami...
Ferritin-catalyzed consumption of hydrogen peroxide by amine buffers causes the variable Fe2+ to O2 stoichiometry of iron deposition in horse spleen ferritin.
Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry    July 29, 2006   Volume 11, Issue 8 1075-1086 doi: 10.1007/s00775-006-0141-6
Zhang B, Wilson PE, Watt GD.Ferritin catalyzes the oxidation of Fe2+ by O2 to form a reconstituted Fe3+ oxy-hydroxide mineral core, but extensive studies have shown that the Fe2+ to O2 stoichiometry changes with experimental conditions. At Fe2+ to horse spleen ferritin (HoSF) ratios greater than 200, an upper limit of Fe2+ to O2 of 4 is typically measured, indicating O2 is reduced to 2H2O. In contrast, a lower limit of Fe2+ to O2 of approximately 2 is measured at low Fe2+ to HoSF ratios, implicating H2O2 as a product of Fe2+ deposition. Stoichiometric amounts of H2O2 have not been measured, and H2O2 is proposed to react ...
Screening for basic drugs in equine urine using direct-injection differential-gradient LC-LC coupled to hybrid tandem MS/MS.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences    April 17, 2006   Volume 836, Issue 1-2 1-14 doi: 10.1016/j.jchromb.2006.03.034
Stanley SM, Foo HC.A rapid, selective and robust direct-injection LC/hybrid tandem MS method has been developed for simultaneous screening of more than 250 basic drugs in the supernatant of enzyme hydrolysed equine urine. Analytes, trapped using a short HLB extraction column, are refocused and separated on a Sunfire C(18) analytical column using a controlled differential gradient generated by proportional dilution of the first column's eluent with water. Independent data acquisition (IDA) was configured to trigger a sensitive enhanced product ion (EPI) scan when a multiple reaction monitoring (MRM) survey scan s...
Protopine alkaloids in horse urine.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences    October 2, 2004   Volume 811, Issue 1 85-91 doi: 10.1016/j.jchromb.2004.03.077
Wynne PM, Vine JH, Amiet RG.Protopine was extracted from Fumaria officinalis and purified by column chromatography. Urine samples were collected from horses and a human volunteer that had been administered either F. officinalis or protopine free base. Plant and urine samples were acetylated and analysed by GCMS after solid-phase extraction (SPE). The urinary metabolites of protopine were identified as 4,6,7,13-tetrahydro-9,10-dihydroxy-5-methyl-benzo[e]-l,3-benzodioxolo [4,5-1][2] benzazecin-12(5H)-one, 4,6,7,13-tetrahydro-10-hydroxy-9-methoxy-5-methyl-benzo[e]-1,3-benzodioxolo[4,5-1][2] benzazecin-12(5H)-one and 4,6,7,1...
A partially unfolded state of equine beta-lactoglobulin at pH 8.7.
Journal of protein chemistry    September 21, 2001   Volume 20, Issue 2 131-137 doi: 10.1023/a:1011029524100
Fujiwara K, Ikeguchi M, Sugai S.The urea-induced unfolding transition of equine beta-lactoglobulin was studied at pH 8.7 using circular dichroism (CD), ultracentrifugation, and gel filtration chromatography. The unfolding transition curves showed that at least one intermediate accumulates at moderate concentrations of urea. Furthermore, analytical ultracentrifugation experiments indicated that the intermediate forms a dimer. Thus, the urea-induced unfolding transition was measured by CD at various protein concentrations and was analyzed by a model assuming the four conformational states (the native, intermediate, dimeric int...
Primary structure of kappa-casein isolated from mares’ milk.
The Journal of dairy research    April 6, 2001   Volume 68, Issue 1 53-61 doi: 10.1017/s0022029900004544
Iametti BS, Tedeschi G, Oungre E, Bonomi F.In this work the purification and the complete primary structure of kappa-casein from equine milk are reported for the first time. Mares' milk casein was separated by RP-HPLC into four fractions. Complete primary sequence was obtained by sequence analysis of the protein in the fastest eluting peak isolated by chromatography. This sequence was 95% identical to that reported for the C-terminal portion of the zebras' kappa-casein and showed high similarity with kappa-caseins from sources other than Equidae, confirming that this protein was indeed kappa-casein in equine milk. The presence of post-...
Influence of bacitracin on microbial functions in the gastrointestinal tract of horses.
Equine veterinary journal    August 22, 2000   Volume 32, Issue 4 345-350 doi: 10.2746/042516400777032165
Collinder E, Berge GN, Grønvold B, Lindholm A, Midtved T, Norin E.This study investigated the influence of zinc bacitracin on the intestinal flora of horses. The functionally active intestinal flora was examined in 6 horses during treatment with zinc bacitracin. Utilising gas chromatography, spectrophotometry, gel electrophoresis and paper chromatography, samples were analysed on biochemical markers reflecting the action of parts of the intestinal flora. The following 5 flora-related functions were studied in faecal samples and intestinal samples from different sections of the hindgut: conversion of cholesterol to coprostanol and of bilirubin to urobilinogen...
Extraction of equine chorionic gonadotrophin from pregnant mare plasma by direct adsorption on chromatographic media.
Biotechnology and bioengineering    April 1, 1999   Volume 57, Issue 1 22-25 
González G, Castro B, Massaldi H.Equine chorionic gonadotrophin (eCG) is a hormone of practical value in veterinary medicine and animal production. Here we report a novel preparation procedure based on its direct adsorption onto anionic-exchange resins in a batch-wise mode. The active plasma is previously conditioned to reduce pH and ionic strength to required levels. After the adsorption stage, a 90% recovery of the initial eCG is achieved, with a concentration factor of about 50 and an enrichment factor around 500, with high preservation of biological activity. Further purification is carried out by cation-exchange column c...
Detection and determination of theobromine and caffeine in urine after administration of chocolate-coated peanuts to horses.
Journal of analytical toxicology    April 21, 1998   Volume 22, Issue 2 112-116 doi: 10.1093/jat/22.2.112
Dyke TM, Sams RA.The objective of this study was to determine the urinary excretion of methylxanthines in horses following ingestion of chocolate over eight days. The study was performed in response to gas chromatography-mass spectrometry (GC-MS) confirmation of the presence of caffeine in a positive urine test in a racehorse. The trainer of the horse alleged that he often administered chocolate-coated peanuts as treats to his horses, and he believed that the ingestion of chocolate was responsible for the positive urine test. The urinary excretion of theobromine and caffeine after the ingestion of chocolate-co...
Quantitative comparison on the refinement of horse antivenom by salt fractionation and ion-exchange chromatography.
Journal of chromatography. B, Biomedical sciences and applications    December 9, 1997   Volume 700, Issue 1-2 233-239 doi: 10.1016/s0378-4347(97)00244-2
Saetang T, Treamwattana N, Suttijitpaisal P, Ratanabanangkoon K.A quantitative comparison was made on the fractionation of pepsin-digested horse antivenoms by ammonium sulfate (AS) fractional precipitation and ion-exchange chromatography on Q-Sepharose. In the precipitation process, pepsin digested horse anti-Naja kaouthia serum was precipitated by 30% saturated AS followed by 50% saturated AS. The recovery of antibody activity [as measured by an enzyme-linked immunosorbent assay (ELISA) against the cobra postsynaptic neurotoxin 3] from the 30-50% saturated AS precipitate was 53% with a 1.93-fold purification. For the chromatographic process, the behavior ...
Variations of equine urinary volatile compounds during the oestrous cycle.
Veterinary research communications    August 1, 1997   Volume 21, Issue 6 437-446 doi: 10.1023/a:1005859419574
Ma W, Klemm WR.Equine urine was analysed by capillary gas chromatography. The volatile profiles from oestrous and dioestrous samples were compared to establish any qualitative or quantitative difference that may have potential value in olfactory communication. Forty-five different volatile compounds were detected. Of these, 17 major compounds were common to all chromatograms. The chemical profile of oestrous urine was distinguished by the presence of a unique peak that was not present in dioestrous samples. Numerous constituents exhibited endocrine dependence: while the concentrations of seix peaks increased...
Low-molecular-weight displacers for high-resolution protein separations.
Analytical biochemistry    May 15, 1997   Volume 248, Issue 1 111-116 doi: 10.1006/abio.1997.2116
Kundu A, Cramer SM.The resolving power of displacement chromatography using low-molecular-weight displacers was investigated using a model mixture containing bovine and horse heart cytochrome c. The linear and nonlinear adsorption behavior of these two proteins was examined in cation-exchange chromatography and shown to be quite similar. Furthermore, an analysis of the dynamic affinity of these proteins indicated extremely similar affinities under displacement conditions. Despite the extreme similarities in the adsorption behavior, displacement chromatography using a protected amino acid displacer resulted in ex...
Novel di-O-acetylated GM3s from equine erythrocytes, one containing 4,9-di-O-acetyl-N-glycolylneuraminic acid and another containing 4-O-acetyl-N-glycolylneuraminic acid and 6-O-acetyl-D-galactose.
Carbohydrate research    March 5, 1997   Volume 298, Issue 3 201-212 doi: 10.1016/s0008-6215(96)00307-2
Yachida Y, Tsuchihashi K, Gasa S.A novel GM3 O-acetylated at C-4 and at C-9 of N-glycolylneuraminic acid (4,9-di-O-Ac GM3), together with a second GM3 O-acetylated at O-4 of the neuraminic acid and O-6 of D-galactose (4,6'-di-O-Ac GM3) were isolated from equine erythrocytes as a mixture in approximate 1:1 ratio. These two major species were chromatographically inseparable. Their structures, especially the positions of the acetoxy group(s), were determined by means of 1D- and 2D-1H NMR and fast atom bombardment-MS as well as by gas chromatography-MS of partially O-methylated O-trimethylsilylated monosaccharides derived from th...
Separation of equine IgG subclasses (IgGa, IgGb and IgG(T)) using their differential binding characteristics for staphylococcal protein A and streptococcal protein G.
Veterinary immunology and immunopathology    December 1, 1996   Volume 55, Issue 1-3 33-43 doi: 10.1016/s0165-2427(96)05618-8
Sheoran AS, Holmes MA.Equine IgG possesses four well-defined subisotypes, designated IgGa, IgGb, IgGc and IgG(T) on the basis of their increasing anodal mobility in electrophoresis. However, the preparation of IgGa and IgGb reference proteins has not previously been reported. Certain bacterial cell wall proteins, termed protein A and protein G, have been used for purification of IgG subisotypes from the serum of domestic animals which, combined with other techniques utilising differences in the physico-chemical properties of the proteins, has allowed the purification of Ig isotypes. This paper describes purificatio...
The structure of the keratan sulphate chains attached to fibromodulin isolated from articular cartilage.
European journal of biochemistry    December 1, 1996   Volume 242, Issue 2 402-409 doi: 10.1111/j.1432-1033.1996.0402r.x
Lauder RM, Huckerby TN, Nieduszynski IA.Fibromodulin has been isolated from bovine and equine articular cartilage and the attached keratan sulphate chains subjected to digestion by keratanase II. The oligosaccharides generated have been reduced and subsequently isolated by strong anion-exchange chromatography. Their structures have been determined by high-field 1H-NMR spectroscopy and high-pH anion-exchange chromatography. Both alpha(2-6)- and alpha(2-3)-linked N-acetylneuraminic acid have been found in the capping oligosaccharides, and, fucose which is alpha(1-3)-linked to N-acetylglucosamine has been found as a branch in both repe...
Quantification of phenylbutazone in equine sera by use of high-performance liquid chromatography with a nonevaporative extraction technique.
American journal of veterinary research    November 1, 1996   Volume 57, Issue 11 1522-1524 
Peck KE, Ray AC, Manuel G, Rao MM, Foos J.To develop a sensitive, rugged high-performance liquid chromatography (HPLC) method for the measurement of phenylbutazone (PBZ) in equine sera, using a rapid, nonevaporative extraction technique. Methods: Sera from 5 nonexercising adult horses. Methods: After addition of sodium chloride and acetonitrile to serum samples, reverse-phase HPLC analysis for PBZ and oxyphenbutazone (OXY) was performed directly on extracts, using diode array UV spectrophotometric detection. Probenecid was used as an internal standard. Data were evaluated by standard means of statistical analysis. Results: Recoveries ...
Diagnosis of oleander poisoning in livestock. Galey FD, Holstege DM, Plumlee KH, Tor E, Johnson B, Anderson ML, Blanchard PC, Brown F.Since mid-1989, 37 cases of oleander poisoning in livestock have been diagnosed at the California Veterinary Diagnostic Laboratory System. The most frequent source for oleander exposure was plant clippings. Sudden death was the most common presenting complaint. Other signs reported included diarrhea, pulmonary edema, tachycardia, cardiac arrhythmias, colic, and lethargy. In the past, a presumptive diagnosis of oleander poisoning could be based only on matching clinical signs with evidence of consumption of oleander. A new 2 dimensional Thin-layer chromatography analysis of ingesta for oleandri...
Glycosylated equine prolactin and its carbohydrate moiety.
Journal of protein chemistry    July 1, 1996   Volume 15, Issue 5 413-426 doi: 10.1007/BF01886848
Butnev VY, Gotschall RR, Baker VL, Moore WT, Gout PW, Bousfield GR.Glycosylated equine prolactin (G-ePRL) and nonglycosylated ePRL were purified to homogeneity from side fractions obtained during isolation of LH/FSH from horse pituitaries. Both PRL forms were isolated together in high yield by the isolation procedure used for glycosylated porcine PRL/(G-pPRL) and pPRL, involving acetone extraction/precipitation, NaCl and isoelectric precipitation, and gel filtration. Purification of G-ePRL required additional Con A chromatography. The N-terminal amino acid sequencing for 32 cycles of G-ePRL and ePRL resulted in sequences identical to the known primary structu...
Detection of non-steroidal anti-inflammatory drugs in equine plasma and urine by gas chromatography-mass spectrometry.
Journal of chromatography. A    January 5, 1996   Volume 719, Issue 1 251-264 doi: 10.1016/0021-9673(95)00370-3
González G, Ventura R, Smith AK, de la Torre R, Segura J.A gas chromatographic-mass spectrometric (GC-MS) procedure for the detection of seventeen non-steroidal anti-inflammatory drugs (NSAIDs) in equine plasma and urine samples is described. The extraction of the compounds from the biological matrix was performed at acidic pH (2-3) with diethyl ether. Ethereal extracts were washed with a saturated solution of sodium hydrogencarbonate (urine) or treated with a solid mixture of sodium carbonate and sodium hydrogencarbonate (plasma). The ethereal extracts were dried and derivatized by incubation at 60 degrees C with methyl iodide in acetone in the pre...
Determination of succinonitrile in horse urine by gas chromatography-nitrogen-phosphorus detector and gas chromatography-mass spectrometry.
The Analyst    December 1, 1994   Volume 119, Issue 12 2697-2699 doi: 10.1039/an9941902697
Pedroso RC, Salvadori MC, Andraus MH, Lopez NM.A chromatographic method was developed to detect and confirm the presence of succinonitrile (SDN) in horse urine samples, for antidoping control. The urine samples (5 ml) were extracted with diethyl ether and screened by gas chromatography-nitrogen-phosphorus detector and the confirmation of the drug's presence was accomplished by using gas chromatography-mass selective detection. The recovery of extraction was 78 and 81% for 1.0 and 2.0 micrograms ml-1 (relative standard deviation, < 10%), respectively. Urine samples collected after the administration of Energisan were positive for SDN (1-30 ...