The samples of whole blood and bloodstain were MN-typed by the method of one-step sandwich ELISA, monoclonal antibodies include anti-M, N and glycern-protein. The lowest sample amount in this study is: for whole blood is 0.065 microliter, for bloodstain about 10 to 50 ng. 455 cases of fresh blood and 200 cases of fresh bloodstain are correctly typed. For 58 cases of old bloodstains, the success rate is 96.6%.
Antibodies, Monoclonal Antigens