Use of molecularly imprinted solid-phase extraction for the selective clean-up of clenbuterol from calf urine.
A feasibility study was performed in order to study the possibilities in using molecularly imprinted polymers (MIPs) as sorbent material in solid-phase extraction (MISPE) for clean-up of clenbuterol from urine. A binding study of clenbuterol in several solvents was performed on a clenbuterol imprinted polymer as well as on a blank polymer. These binding experiments were used to find suitable loading, washing and elution solvents for the MISPE procedure. Extraction of clenbuterol from calf urine was performed by directly loading a 10-ml urine sample onto the MIP column. Thereafter the column was washed with 10 ml of acetonitrile containing 1% acetic acid, and finally clenbuterol was eluted with 6 ml of methanol containing 10% acetic acid. A recovery of 65% was obtained. This recovery could be increased up to 75% if a sample volume of 1 ml was used or up to 100% if urine was freeze-dried and the residue was dissolved in acetonitrile and spiked with clenbuterol prior to analysis. Chromatograms of the wash and eluate solutions show an efficient clean-up, which supports the potential of MISPE for clean-up of trace amounts of clenbuterol from calf urine.
Berggren
C
C
Department of Analytical Chemistry and Toxicology, University Centre for Pharmacy, Groningen, The Netherlands.
Bayoudh
S
S
Sherrington
D
D
Ensing
K
K
D000318:Adrenergic beta-Agonists / Q000302:isolation & purification / Q000652:urine; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002976:Clenbuterol / Q000302:isolation & purification* / Q000652:urine; D019411:Clinical Laboratory Techniques; D005240:Feasibility Studies
D000318:Adrenergic beta-Agonists; D002976:Clenbuterol