Preparation and identification of artificial antigen for digoxin and determination of its immune titers

OBJECTIVE To prepare artificial antigen and antiserum of digoxin(Dig) and determine its immunogenicity for later production of monoclonal antibody against Dig.METHODS Dig was conjugated with bovine serum albumin(BSA) and ovalbumin(OVA) using periodate oxidation method to obtain the Dig-BSA and Dig-OVA conjugate,the conjugate and the hapten number in the conjugate was determined by UV-Vis spectrophotometry(UV) and matrix-assisted laser absorption ionization time-of-flight mass spectrometry(MALDI-TOF-MS);BALB/c mice were immunized with Dig-BSA to prepare the antiserum against Dig,The serum titer of the Dig antibodies were detected by enzyme-linked immunosorbent assay(ELISA) which based upon Dig-OVA.RESULTS The conjugation ratio of Dig and the carrier protein BSA was about 5∶1;The antiserum against Dig with a titer of 1∶62 500 was obtained after immunizing the mice with the Dig-BSA conjugate.CONCLUSION The synthesized Dig-BSA conjugate possesses good immunogenicity in mice,suggesting the feasibility of preparing the monoclonal antibody against Dig using this conjugate.