设计合成了一种长臂发夹型核酸探针,结合核酸外切酶Ⅲ水解反应建立了一种免标记荧光信号放大高灵敏检测DNA的新方法。当不存在靶DNA时, SYBR Green Ⅰ荧光染料能够嵌入发夹型探针的茎部而发出很强的荧光,而当存在靶DNA并与发夹型探针杂...设计合成了一种长臂发夹型核酸探针,结合核酸外切酶Ⅲ水解反应建立了一种免标记荧光信号放大高灵敏检测DNA的新方法。当不存在靶DNA时, SYBR Green Ⅰ荧光染料能够嵌入发夹型探针的茎部而发出很强的荧光,而当存在靶DNA并与发夹型探针杂交后,核酸外切酶Ⅲ从杂交产物的3’端开始水解发夹型探针,释放出靶DNA,并触发下一个酶水解反应,同时SYBR Green Ⅰ染料也随发夹型探针水解而释放,导致荧光信号降低,从而实现了对DNA的免标记荧光信号放大高灵敏检测。该方法的检出限低至320 fmol/L,比传统双标的分子信标的方法降低了4~5个数量级,且该方法还具有免标记、简单、快速的特点。展开更多
The interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA has been studied by UV-Vis spectral, Fluorescence spectral in buffer solution of Tris-HCl (pH=7.25) using Neutral Red (NR) as a probe. The intercalati...The interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA has been studied by UV-Vis spectral, Fluorescence spectral in buffer solution of Tris-HCl (pH=7.25) using Neutral Red (NR) as a probe. The intercalation and electrostatic manner are confirmed to be the two major modes for interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA. The balance constant of Sm(Ⅲ)(MTB)2 rare earth metal complex and Herring Sperm DNA is K=4.10 × 104 L·mol-1. The results indicate that biological functions of Herring Sperm DNA are changed to a certain extend due to the interaction between Sm(Ⅲ)(MTB)2 rare earth metal complex and Herring Sperm DNA.展开更多
文摘设计合成了一种长臂发夹型核酸探针,结合核酸外切酶Ⅲ水解反应建立了一种免标记荧光信号放大高灵敏检测DNA的新方法。当不存在靶DNA时, SYBR Green Ⅰ荧光染料能够嵌入发夹型探针的茎部而发出很强的荧光,而当存在靶DNA并与发夹型探针杂交后,核酸外切酶Ⅲ从杂交产物的3’端开始水解发夹型探针,释放出靶DNA,并触发下一个酶水解反应,同时SYBR Green Ⅰ染料也随发夹型探针水解而释放,导致荧光信号降低,从而实现了对DNA的免标记荧光信号放大高灵敏检测。该方法的检出限低至320 fmol/L,比传统双标的分子信标的方法降低了4~5个数量级,且该方法还具有免标记、简单、快速的特点。
文摘The interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA has been studied by UV-Vis spectral, Fluorescence spectral in buffer solution of Tris-HCl (pH=7.25) using Neutral Red (NR) as a probe. The intercalation and electrostatic manner are confirmed to be the two major modes for interaction between Sm(Ⅲ)(MTB)2 complex and Herring Sperm DNA. The balance constant of Sm(Ⅲ)(MTB)2 rare earth metal complex and Herring Sperm DNA is K=4.10 × 104 L·mol-1. The results indicate that biological functions of Herring Sperm DNA are changed to a certain extend due to the interaction between Sm(Ⅲ)(MTB)2 rare earth metal complex and Herring Sperm DNA.
基金supported by the National Natural Science Foundation of China(20972015)the Natural Science Foundation of Beijing(Grant2082016)a joint project of Beijing Municipal Education Commission(China)
