Abstract: We have devloped an enzyme-linked immunosorbent assay for quantitative analysis of abscisic acid (ABA) by coupling horseradish peroxi-dase (HRP)to ABA directly as an enzyme conjugate.The sensitivity of the assay,50 f mol, is comparable to the radioimmunoassay and the established methods using alkaline phosphatase (AP) -ABA or ABA-bovineserum albumin-AP as the enzyme conjugate.The logit B/B 0 value was linear between 12.5 pg to 100 ng. For improving assay sensitivity and precicion,we have also spproachedtion scheduies, injection doses and route, enzyme conjugate concentration and the dilution of antibody against ABA.

Key words: ABA

摘要： 使用国产辣根过氧化物酶（HRP ) 合成酶标记物，用竞争法进行了植物内源激素脱落酸（ABA ) 的酶标免疫测定研究。测定范围为0．0125 ng - 10O ng，在此范围内logitB／B。与ABA 浓度的对数之间呈较好的线性关系。检测的灵敏度达到5×10-14克分子。比较了两种酶标记方法对于测定的影响，结果发现直接使ABA共价结合到HRP上形成ABA－HRP梅标记物比先将ABA与牛血清白蛋白（BSA）结合后，然后进一步再与HRP反应形成ABA一BSA一HRP复合物灵敏度高，非特异性吸附小，而且合成步骤较少。酶标记物的稀释度直接影响测定的灵敏度和浓度对数与logit B/B.之间线性关系好坏；在以每毫升3- 6微克免疫球蛋白包埋免疫吸附板进行测定时，用每毫升5微克酶标记物的浓度获得了最佳结果。

关键词: 脱落酸, 酶标免疫测定, 辣根过氧化物酶