Using molecular descriptors for assisted screening of heterologous competitive antigens to improve the sensitivity of ELISA for detection of enrofloxacin in raw milk.

The use of the heterologous competitive strategy has become a vital method to improve the sensitivity of ELISA. In this work, we prepared an anti-enrofloxacin (ENR) mAb with ENR-bovine serum albumin (BSA) as immunogen. The molecular descriptors of quinolones were then used to screen heterologous coating antigens for the detection of ENR based on an ensemble learning method to improve the sensitivity of the ELISA. Results indicated that 6 of the 7 selected heterologous competitive antigens could enhance the sensitivity of ELISA. The ELISA sensitivity for the detection of ENR with sarafloxacin-BSA as heterologous coating antigen was improved 10-fold (in PBS) and 6-fold (in milk) compared with that with ENR-BSA as homologous antigen. The strategy can effectively screen suitable heterologous competitive antigens to improve the sensitivity of ELISA, followed by preparation of mAb with no additional modification to the corresponding immunogen.