Those antibodies elicited by different tether site for attachment to carrier protein differ geratly in specificity. In order to reduce cross reactivity and enhance the specific recognition between the antibody and free morphine, the hapten was synthesized by the modification in N-site of morphine. The conjuagtes of hapten and proteins, used to immunize and screen, were prepared respectively by using different linkers to couple to different carrier proteins, and the 5 murine monoclonal antibodies against morphine, 28H10, 29D5,36G3, 42D5 and 43C4 were produced.

Key words: MORPHINUM, MONOCLONAL ANTIBODY, PROTEIN, COUPLED