Protein microarray: Sensitive and effective immunodetection for drug residues

Li Zhong, Wei Zhang, Cindy Zer, Kun Ge, Xu Gao, Kemp H. Kernstine

Research output: Contribution to journalArticlepeer-review

9 Scopus citations


Background: Veterinary drugs such as clenbuterol (CL) and sulfamethazine (SM2) are low molecular weight (<1000 Da) compounds, or haptens, that are difficult to develop immunoassays due to their low immunogenicity. In this study, we conjugated the drugs to ovalbumin to increase their immunogenicity for antiserum production in rabbits and developed a protein microarray immunoassay for detection of clenbuterol and sulfamethazine. The sensitivity of this approach was then compared to traditional ELISA technique.Results: The artificial antigens were spotted on microarray slides. Standard concentrations of the compounds were added to compete with the spotted antigens for binding to the antisera to determine the IC50. Our microarray assay showed the IC50 were 39.6 ng/ml for CL and 48.8 ng/ml for SM2, while the traditional competitive indirect-ELISA (ci-ELISA) showed the IC50 were 190.7 ng/ml for CL and 156.7 ng/ml for SM2. We further validated the two methods with CL fortified chicken muscle tissues, and the protein microarray assay showed 90% recovery while the ci-ELISA had 76% recovery rate. When tested with CL-fed chicken muscle tissues, the protein microarray assay had higher sensitivity (0.9 ng/g) than the ci-ELISA (0.1 ng/g) for detection of CL residues.Conclusions: The protein microarrays showed 4.5 and 3.5 times lower IC50 than the ci-ELISA detection for CL and SM2, respectively, suggesting that immunodetection of small molecules with protein microarray is a better approach than the traditional ELISA technique.

Original languageEnglish (US)
Article number12
JournalBMC Biotechnology
StatePublished - Feb 16 2010

ASJC Scopus subject areas

  • Biotechnology


Dive into the research topics of 'Protein microarray: Sensitive and effective immunodetection for drug residues'. Together they form a unique fingerprint.

Cite this