不同生物素检测系统在核酸分子杂交检测中的应用——Ⅲ 链霉亲和素-碱性磷酸酶标记生物素检测系统

Application of Different Assay Systems for Biotinylated Probe in Hybridization Ⅲ Streptavidin—alkaline phosphatase conjugated biotin complex system

使用链霉亲和素(sA)结合碱性磷酸酶标记生物素(B-Ap)对斑点杂交结果进行检测。先摸索出sA和B-Ap的最佳浓度比。当反应液中sA浓度为1μg/ml,sA和B-Ap浓度比为1.7～2.0时,斑点杂交检测敏感性可达到pg水平。

Two assay systems—the alkaline phosphatase conjugated avidin (A-Ap) and the colloidal gold conjugated streptavidin(sA-gold) were used to detect biotinylated probe in hybridization. The non-specific binding between nucleic acids and A-Ap could be eliminated by elevating the ionic concentration or pH value of the reaction solution. The detection limit was about 1pg when A-Ap was used as a assay system, But when the filter was developed with sA-gold, only 12.5ng target DNA could be detected.