An exploratory study on the simultaneous screening for residues of chloramphenicol, ciprofloxacin and sulphadimidine using recombinant antibodies

A recombinant gene CCS consisting of three single genes (CAP-ScFv, CPFX-ScFv and SM2-ScFv) were constructed by PCR with three pairs of primers. The length of CCS gene fragment was 2,260 bp. A recombinant plasmid (pGEX-CCS) was obtained in pGEX-6p-1. pGEX-CCS was induced in E.coli BL21(DE3), and the molecular weight of recombinant fusion protein (GST-CCS) was 108.87 kDa. GST-CCS was successfully applied to analysis of CAP-OVA (CAP-ovalbumin conjugate), CPFX-OVA and SM2-OVA simultaneously. The sensitivity of GST-CCS against three veterinary drugs was tested by indirect ELISA at dilution ratio 1:8000. These findings provide a foundation for the construction of fusion genes with linkers and for the potential development of a rapid screening method for the simultaneous detection of veterinary drug residues.