Clenbuterol Assay by Spectral Imaging Surface Plasmon Resonance Biosensor System

Abstract

To prevent illegal use of clenbuterol and for quality control in the food industry, more efficient and reliable methods for clenbuterol detection are needed. In this study, clenbuterol was detected using a spectral imaging surface plasmon resonance sensor system via two inhibition methods: (1) the target site compensation method, in which anti-clenbuterol antibody was immobilized on the sensor chip as a bioprobe and (2) the solution competition method in which a clenbuterol-BSA conjugate was immobilized on the sensor chip as the bioprobe. The detectable clenbuterol concentration ranged between 6.25 and 100 μg/mL for both methods. The clenbuterol limit of detection for the target site compensation method and solution competition method are estimated to be 6.7 and 4.5 μg/mL, respectively. The proposed methods were successfully applied to the detection of clenbuterol molecules and were found to have high specificity and high-throughput and were label free and operationally convenient.

Mechanism of surface plasmon resonance sensing by indirect competitive inhibition immunoassay using Au nanoparticle labeled antibody

“…In contrast, LOD was only 2 ppt (2 pg mL −1 ) for the unlabeled Ab, which was approximately 40 times higher than that of the Ab-AuNP conjugate. To the best of our knowledge, such extremely high sensitivity has not been reported for the detection of clenbuterol [ELISA: 100-25 pg mL −1 [27,33]; amperometry: 1.3 pg mL −1 [34]; fluorescence spectroscopy: 0.12 µg L −1 [35]; SPR: 2.0 µg L −1 [36]; Spectral Imaging SPR: 6.7-4.5 µg mL −1 [37]. Sensitivity enhancement can be explained by kinetic analysis of the indirect competitive inhibition immunoassay.…”