Clenbuterol confirmation

Elliott et al. utilized a clenbuterol immunoassay to determine clenbuterol residues in cattle tissues and fluids. The LOD was 0.25 ug for liver. Animals were dosed with medicated feed (1.6 ug kg per day), and pairs were slaughtered during the medication phase and at 14,28, and 42 days after withdrawal. Clenbuterol concentrations in liver and retina/choroid samples were confirmed by GC/MS. Correlation coefficients between the ELISA and GC/MS were = 0.92 for retina/choroid samples and... 

Shelver and Smittf confirmed fhaf commercial clenbuterol immunoassays cross-react with some, but not all, clenbuterol metabolites. As a result, quantitative clenbuterol immunoassays may differ from determinative methods if substantial concentrations of metabolites are present. For clenbuterol, the parent clenbuterol level is... 

The FDA/FSIS survey lasted to 1997. Only 1 of the 499 eyeball samples gave a positive result with the ELISA screen, but the presence of clenbuterol could not be confirmed in this sample. Confirmatory analysis showed that this animal contained residues of the -agonist fenoterol. 

Hoffman RJ, Hoffman RS, Freyberg CL, Poppenga RH, Nelson LS. Clenbuterol ingestion causing prolonged tachycardia, hypokalemia, and hypophosphatemia with confirmation by quantitative levels. J Toxicol Clin Toxicol 2001 39(4) 339-44. 

When an SPE sorbent shows good performance with an analyte its fitness for other analytes, however close in structure, should be experimentally confirmed. A case in point is the forensic analysis of the adrenergic agonists Clenbuterol (70) and Compound A (71), both forbidden for use as animal feed additives. Four types of sorbents were tested—cyanopropyl resin, sulfonic acid SCX, mixed SCX + Qg and nonendcapped ( is only the latter type was found to quantitatively extract 71 although the performance of all four was satisfactory for 70. End analysis was by GC-MS-MS127. 

Drug adulteration Adulteration of heroin with clenbuterol is frequently reported [112 ]. In 13 confirmed cases of exposure to clenbuterol in this way, clenbuterol was identified in the blood and or urine of 12 [113 ]. Symptoms included nausea, chest pain, palpitation, dyspnea, and tremor. The physical findings included significant tachycardia and hypotension, and there was laboratory evidence of hyperglycemia, hypokalemia, and increased lactate concentrations six patients had biochemical evidence of myocardial injury. Ten were given beta-adrenoceptor antagonists without adverse effects. 

Clenbuterol was detected in 12 of 106 postmortem cases in the USA in which the cause of death was attributed to illicit drug use [114 ]. In each case heroin use was either confirmed by the presence of 6-acetylmorphme or strongly suspected by the presence of morphine with a history of heroin abuse. The authors suggested that one should test for clenbuterol when treating a suspected heroin user with an atypical presentation. 

Amendola, L., Colamonici, C, Rossi, E, and Botre, F. (2002) Determination of clenbuterol in human urine by GC-MS-MS-MS Confirmation analysis in antidoping control. Journal of Chromatography B, Analytical Technologies in the Biomedical and Life Sciences, 773,7-16. 

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