Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, China.
Anal Chim Acta. 2011 Nov 7;706(1):171-5. doi: 10.1016/j.aca.2011.08.032. Epub 2011 Aug 30.
Carbon nanotubes (CNTs) can efficiently quench the fluorescence of the adsorbed fluorophores and nonconvalently interact with soft single-stranded DNA (ssDNA). Upon disruption of CNTs-fluorescent oligonucleotides hybrid by nuclease S1, fluorescence turn-on was observed. Using this strategy, a platform based on fluorescence signal for monitoring the activity of nuclease with advantages of high sensitivity and commonality was established, and a linear relationship between initial cleavage reaction rate and nuclease S1 concentration is found in the range of 0.6-8.0 U mL(-1) with a detection limit of 0.08 U mL(-1). Furthermore, by taking pyrophosphate as an example, we use the assay to evaluate the prohibition effect on nuclease, and the extent of fluorescence recovery decreased linearly with increasing the concentration of pyrophosphate in the range of 0.2-1.4 mM, implying that the cleavage reaction by nuclease S1 was prohibited, and therefore this fluorescence assay can also be conveniently utilized for inhibitor screening of nuclease.
碳纳米管 (CNTs) 可以有效地猝灭被吸附荧光团的荧光，并与软单链 DNA (ssDNA) 非共价相互作用。当核酸酶 S1 破坏 CNTs-荧光寡核苷酸杂交时，观察到荧光开启。利用该策略，建立了基于荧光信号的平台，用于监测核酸酶的活性，具有高灵敏度和通用性的优点，并且在 0.6-8.0 U mL(-1) 的范围内发现初始切割反应速率与核酸酶 S1 浓度之间存在线性关系，检测限为 0.08 U mL(-1)。此外，通过以焦磷酸为例，我们使用该测定法评估对核酸酶的抑制作用，并且荧光恢复的程度随焦磷酸盐浓度在 0.2-1.4 mM 的范围内线性增加而降低，表明核酸酶 S1 的切割反应被抑制，因此该荧光测定法也可方便地用于核酸酶抑制剂的筛选。
