Objective   To prepare huperzine A-carrier protein conjugate and determine its immunogenicity for later production of monoclonal antibody against HupA and establishing an enzyme-linked immunosorbent assay (ELISA)-based detection method for HupA.   Methods   HupA was conjugated with bovine serum albumin (BSA) using glutaraldehyde (GA) method to obtain the HupA-GA-BSA conjugate

and the hapten number in the conjugate was determined by matrix-assisted laser absorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). BALB/c mice were immunized with HupA-GA-BSA to prepare the antiserum against HupA. The serum titer and specificity of the HupA antibodies were detected by indirect ELISA and competitive ELISA

respectively.   Results   The conjugation ratio of HupA and the carrier protein BSA was 8∶1. The antiserum against HupA with a titer of 1∶62 500 was obtained after immunizing the mice with the conjugate

and the antiserum reacted specifically to HupA.    Conclusion   The synthesized HupA-GA-BSA conjugate possesses good immunogenicity in mice

suggesting the feasibility of preparing the monoclonal antibody against HupA using this conjugate.