Preparation And Identification Of Monoclonal Antibodies Against Levofloxacin

The purpose of this study was to prepare a high specific levofloxacin monoclonal antibodies. In order to detect the specificity of the single resistance, this study use of monoclonal antibodies to levofloxacin purification, molecular weight determination, and a series of cross reaction method for identification. The detail is as follows:1. The levofloxacin was conjugated directly to bovine serum albumin (BSA) and ovalbumin (OVA) by EDC method. The conjugates LVL -BSA and LVL-OVA were analyzed by SDS-PAGE electrophoresis and ultraviolet absorb spectral curve method, the molecule conjugate ratio of LVL to BSA and OVA were 6:1 and 12:1 respectively. To immunize BALB/c mice using LVL-BSA, the six mice immune serum antibody titer all reached 1:8 000, which is indicatived that the good immune effect. In order to prove that the OVA-LVL as a bag was antigen is feasible, adopt ELISA test positive serum and results showed that feasible.2. BALB/c mice were chosen from six BALB/c mice immunized with LVL-BSA for cell fusion by the titer of indirect ELISA. Three hybridoma lines of 1E4, 4F4 and 3G8 that secrete LVL mAb were screened by indirect ELISA. The indirect ELISA titers of them were 1:1 000, 1:500 and 1:640 in supernatant, 1:6.4×10³,1:4×10³,1:3.2×10³ in ascites respectively, the isotype of them was IgG₁ and the affinity constant(Ka) was 1.27×10⁹. This research done with levofloxacin single resistance ofloxacin cross reaction. The rate of cross reaction of LVL-McAb with ofloxacin, lomefloxacin, ciprofloxacin was 95%, 0.25% and 0.06%. There was no cross reaction between McAb-LVL and cefadroxil, chloramphenicol and SMM.