Abstract
Application of acid elution to absorption-elution test for ABO blood-typing using commercial monoclonal antibodies was described. Collodion plates to fix blood or body fluid samples were introduced for the convenience of treatment of a lot of test samples. For evaluating the optimum elution condition, the amounts of the antibodies eluted were semi-quantitatively determined using enzyme-linked immunosorbent assay (ELISA). The optimum pH for elution was between 3.0 and 3.5 and a remarkable deactivation of antibodies under strong acid condition was observed. Therefore, the accurate pH control was required for effective elution. Elution time was decided at 10 min because the active antibodies were eluted within a few minutes and were maintained during subsequent 20 min. Under these optimum conditions, the absorption-elution test with indicator cells was achieved using some antibodies suitable for acid elution. We also obtained a good result at the preliminary test for an automatic blood-typing system using collodion plate and the acid elution method combined with ELISA. The technique described in this report was considered to be helpful to establish a full automatic blood-typing system for forensic specimen.
