title: Accumulation of the beta(2)-adrenergic agonist clenbuterol in mouse dark hair.
abstract: The aim of the present study was to evaluate the suitability of dark hair as a matrix for determination of the beta(2)-adrenergic agonist clenbuterol residues using previously validated enzyme-linked immunosorbent assay (ELISA) as a screening method for its quantitative determination. The experimental group of mice (n = 60) were treated with two different anabolic dosages of clenbuterol for 15 days, whereas the control group of animals (n = 30) was left completely untreated. Hair samples were collected on days 0, 5, 10, and 15 of treatment. Validation of the ELISA analytical procedure showed good recovery (mean recovery 74%) with an acceptable intra-assay variation in individual measurements for all hair samples to which 5, 10, and 50 ng/g clenbuterol were added (CV < 10%). Low blank levels of clenbuterol (2.4 +/- 0.6 ng/g) were measured in hair of untreated mice, whereas significantly higher clenbuterol concentrations rising proportionally with the time of treatment were recorded in hair of mice treated with lower (6.5 mg/kg body mass) and higher (12.5 mg/kg body mass) dose of clenbuterol. The peak hair concentration of clenbuterol measured on the last day of treatment (day 15) was 1553.9 +/- 140.1 ng/g and 6248.3 +/- 589.4 ng/g in the lower and higher dose group, respectively. Study results clearly indicated dark hair as a pigmented tissue to have a high accumulation potential for clenbuterol residues, thus being the target matrix of choice for detection of clenbuterol abuse as an anabolic in meat production.
authors.affiliation: Laboratory for Analytical Chemistry, Croatian Veterinary Institute, Savska 143, 10 000, Zagreb, Croatia. pleadin@veinst.hr
authors.forename: Jelka
authors.initials: J
authors.lastname: Pleadin
authors.forename: Tihomira
authors.initials: T
authors.lastname: Gojmerac
authors.forename: Zoran
authors.initials: Z
authors.lastname: Lipej
authors.forename: Mario
authors.initials: M
authors.lastname: Mitak
authors.forename: Dinko
authors.initials: D
authors.lastname: Novosel
authors.forename: Nina
authors.initials: N
authors.lastname: Persi
mesh_terms: D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000818:Animals; D002976:Clenbuterol / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D004350:Drug Residues / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006197:Hair / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D010858:Pigmentation; D014018:Tissue Distribution
chemical_list: D000318:Adrenergic beta-Agonists; D002976:Clenbuterol