A highly sensitive detection of chloramphenicol based on chemiluminescence immunoassays with the cheap functionalized Fe3 O4 @SiO2 magnetic nanoparticles.

Abstract

A strategy has been applied to chloramphenicol (CAP) detection with chemiluminescence immunoassays (CLIA) based on cheap functionalized Fe3 O4 @SiO2 magnetic nanoparticles (Fe-MNPs). The strategy that bovine serum albumin (BSA) was immobilized on cheap functionalized Fe-MNPs and that the CAP molecules were then immobilized on BSA, avoided the long process of dialysis for preparation of the BSA-CAP conjugates. The samples were detected for both methods that utilized two different kinds of functionalized Fe-MNPs (amine-functionalized Fe3 O4 @SiO2 and carboxylic acid-functionalized Fe3 O4 @SiO2 ). The sensitivities and limits of detection (LODs) of the two methods were obtained and compared based on inhibition curves. The 50% inhibition concentrations (IC50 ) values of the two methods were about 0.024ng ml-1 and 0.046ng ml-1 respectively and LODs were approximately 0.0002ng ml-1 and 0.001ng ml-1 respectively. These methods were much more sensitive than that of any traditional enzyme-linked immunosorbent assay (ELISA) previously reported. Therefore, such chemiluminescence methods could be easily adapted for small molecule detection in a variety of foods using Fe-MNPs.