In conclusion, a new rapid method was developed for assessing the kinetics of the antigenicity in HBsAg in VLPs with t1/2 ~ 6–10 h under the conditions studied. The rapid, near real time monitoring of the immature-mature epitope continuum was achieved through the use of a neutralizing mAb on a SPR platform. This work demonstrated the importance of the correct disulfide bond pairings for HBsAg VLPs to resemble more closely to the native like virions antigenically and this is likely true for other recombinant Cys containing capsids or envelope proteins. For VLP Dapagliflozin production, conditions should be made conducive to the formation and/or exchange to native-like disulfides for the proper presentation of antigenic features in VLPs or chimeric VLPs [17]. VLP based vaccine design is gaining more attention due to the success of HBV and human papilloma virus vaccines [17]. Most of virus capsid protein or envelope proteins exist as dimeric or oligomeric forms [18], [19], [20] and [21]. The disulfide network could be the intrinsic conformational switches for virions to uncoat in the endoplasmic reducing environment. Thus, for a recombinant vaccine candidate, the surface epitopes on VLPs should strongly resemble the native virion epitopes where the correct disulfide bond pairing is likely a key requirement for shaping up the authentic epitopes. The method presented here should facilitate the characterization of some key epitopes or the tracking of the epitope development on the purified VLPs.