Rapid Determination of Clenbuterol in Urine by a Competitive Bead Immunoassay Based on Luminex Technology

Abstract

A new competitive bead immunoassay (CBIA) based on Luminex technology for detecting clenbuterol in urine was reported. The carboxylated fluorescent beads were directly coated with clenbuterol derivatives without carrier protein spacer. Clenbuterol antibody was biotinylated, which was used for clenbuterol detection in combination with the functionalized bead and streptavidin-phycoerythrin (SAPE). The effects of spacer on the CBIA method were investigated. The results indicated that the presence of small molecular spacer between bead and hapten improved the assay sensitivity and the hydrophilic spacer (glycine) was better than the hydrophobic spacer (m-aminobenzoic acid) for this CBIA method. The study affirms the importance of the judicious choice of hapten derivatives in the CBIA method for detecting small molecule drug based on Luminex technology. The method could be used for clenbuterol detection in livestock urine and possible for the simultaneous detection of multiple veterinary drugs.

Keywords:

• Competitive bead immunoassay
• Clenbuterol
• Spacer

ACKNOWLEDGMENTS

The authors gratefully acknowledge the financial support by Social Development Program of Jiangsu Province (No. BE2008628 and no.BE2009628) and the Fundamental Research Funds for the Central Universities (JUSRP10921).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.