Wang Yanyan, Liu Bin
Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore.
Analyst. 2008 Nov;133(11):1593-8. doi: 10.1039/b806908e. Epub 2008 Aug 6.
A simple and sensitive method for ATP detection using a label-free DNA aptamer as the recognition element and ethidium bromide (EB) as the signal reporter is reported. The ATP-binding aptamer undergoes a conformational switch from the aptamer duplex to the aptamer/target complex upon target binding, which induces the fluorescence change of intercalated EB emission. Good selectivity between ATP and CTP, GTP or UTP has been demonstrated, which is due to the specific recognition between the ATP aptamer and ATP. Using EB alone as a signal reporter, the ATP detection limit was estimated to be approximately 0.2 mM. When a light harvesting cationic tetrahedralfluorene was used as an energy donor to sensitize the intercalated EB emission, a 10-fold increase in detection limit and a 2-fold increase in detection selectivity was demonstrated. The sensitivity and selectivity of the tetrahedralfluorene sensitized assay is comparable to or better than most fluorescent ATP assays with multiple labels.
报道了一种简单灵敏的ATP检测方法，该方法使用无标记的DNA适体作为识别元件，溴化乙锭（EB）作为信号报告分子。ATP结合适体在与靶标结合时会发生从适体双链体到适体/靶标复合物的构象转换，这会诱导插入的EB发射荧光发生变化。已证明ATP与CTP、GTP或UTP之间具有良好的选择性，这是由于ATP适体与ATP之间的特异性识别。仅使用EB作为信号报告分子时，ATP检测限估计约为0.2 mM。当使用光捕获阳离子四面体芴作为能量供体来敏化插入的EB发射时，检测限提高了10倍，检测选择性提高了2倍。四面体芴敏化检测的灵敏度和选择性与大多数多标记荧光ATP检测相当或更好。
