[Preparation of monoclonal antibody against azithromycin and establishment of immunoassay for azithromycin].

Objective To prepare mouse monoclonal antibody (mAb) with haptens of azithromycin (AZM) and characterize its features. Methods The immunogen AZM-BSA and coating antigen AZM-OVA were synthesized by coupling AZM to the bovine serum albumin (BSA) and ovalbumin (OVA) with the activated ester method. Hybridoma cell line 50D10 was obtained by fusing mouse myeloma cells Sp2/0 with splenocytes from the BALB/c mice immunized with AZM-BSA. The cell line was then injected into BALB/c mice to prepare mAb against AZM, which was detected by ELISA using this mAb. Results The titer of AZM mAb was 1:4.0×105, which belonged to IgG1 type. The sensitivity and IC50 of the indirect competitive ELISA was 0.287 µg/L and 1.33 µg/L, respectively. The cross-reactivity rates of the mAb with erythromycin, roxithromycin, doramectin, clarithromycin, tilmicosin and tylosin were less than 0.1%. The recovery rates of AZM added into milk ranged from 79.6% to 104.1% with the coefficients of variation between 16.4% and 27.3%. Conclusion AZM mAb with high sensitivity and specificity has been prepared, which lays a foundation for establishing a method to rapidly detect AZM.

Development of a direct competitive enzyme-linked immunosorbent assay using a sensitive monoclonal antibody for bisphenol A.

To set up an immunoassay-based method to detect Bisphenol A (BPA), we generated a monoclonal antibody (MAb) using a specially designed carboxyl derivative of BPA as the immunogen. BPA-HS was synthesized by reaction using BPA and succinic anhydride. The mice were immunized with the BPA-HS-BSA conjugate. The MAb was obtained from a hybridoma. In addition, we showed that the MAb was highly specific for BPA. The limit of detection was approximately 0.05 ng mL(-1) (ppb) in assay buffer and 0.1 ng mL(-1) (ppb) in water samples. The recoveries of BPA for water samples were from 90.8% to 114%, and coefficients of variation were from 15.6% to 39.4%. Thus, the ELISA method is a rapid and high throughput screening tool to detect BPA in water products.