Spectral surface plasmon resonance imaging for the detection of clenbuterol via three-dimensional immobilization of bioprobes

A method of immobilizing clenbuterol (CLEN) on the sensor chip for spectral surface plasmon resonance imaging (SPRi) was experimentally investigated. The bioprobes on the sensor chip were prepared by immobilizing bovine serum albumin (BSA) protein and conjugating CLEN molecules to BSA, which provides more active points and free orientations for specific binding. The calibration curve showed that the wavelength resonance shift decreased as the concentration of CLEN analyte increased, consistent with the inhibition principle. The limit of detection (LOD) was estimated to be 6.32 μg/ml. This method proved to be highly specific, high throughput, label free, and operationally convenient.