Bovine urine

J. Cai and J. Henion, Quantitative multi-residue determination of /3-agonists in bovine urine using on-line immunoaffinity extr action-coupled column packed capillary liquid cliromatogr aphy-tandem mass spectr ometry , 7. Chromatogr. 691 357-370 (1997). 

Figure 10 Image obtained after performance of 40 clenbuterol assays on 10-fold diluted bovine urine samples (in duplicate), as detected on X-ray film Column 1 and 8 contain standards 0,0.3, 0.6,1.2, 2.5,5, 10, and 20 ppb, from bottom to top, respectively. Columns 2, 4, 6, 9, and 11 contain samples 1-40, with their duplicates in columns 3, 5, 7, 10, and 12. Sample 14 (columns 4 and 5, third from bottom) was later determined using GC-MS to contain 1 ppb of clenbuterol. In all other samples no clenbuterol or other P-agonists could be detected.

Marine Sponge Dictyodendrilla verongiformis Bovine urine... 

Some neuroleptic agents, like cycloindole (497), which has a modified tryptamine structure, and flucindole (498), a difluoro analog of cycloindole, have found use in therapy because of their anti-depressant and anti-psychotic activity (463,464) (Scheme 4.11). 3-Chlorocarbazole (385) (see Scheme 2.102), isolated from female bovine urine, has Diazepam-like activity (354). 

Use of polyclonal antibodies in immunoaffinity cleanup of drug residues was first made in the determination of U enbolone in bovine urine by thin layer chromatography-liquid chromatography (TLC-LC) (173). The polyclonal antibody used was capable to bind both the active form 17- -trenbolone and its... 

Instead of using human serum albumin as a carrier protein, other workers (135) utilized ovalbumin for preparing the diazotized clenbuterol antigen in an enzyme immunoassay developed for screening of clenbuterol residues in bovine urine, liver, and eye. Alkaline phosphatase rather than -galactosidase was also used as an enzyme label in the preparation of the enzyme-clenbuterol conjugate. 

Owing to its high specificity and sample cleanup efficiency, immunoaffinity chromatography has also received widespread acceptance for the determination of -agonists in biological matrices (470, 471, 473, 475, 479, 487, 490). The potential of online immunoaffinity extraction for the multiresidue determination of -agonists in bovine urine was recently demonstrated, using an automated... 

Confirmatory analysis of suspected liquid chromatographic peaks can be made possible by coupling liquid chromatography with mass spectrometry. Ion spray LC-MS-MS has been used to monitor five -agonists in bovine urine (490), while atmospheric-pressure chemical ionization LC-MS-MS has been employed for the identification of ractopamine residues in bovine urine (472). 

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