Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Biosens Bioelectron. 2018 May 15;105:1-5. doi: 10.1016/j.bios.2018.01.017. Epub 2018 Jan 9.
Abnormal concentrations of ATP are associated with many diseases and cancers, and quantitative detection of ATP is thus of great importance for disease diagnosis and prognosis. In the present work, we report a new dual recycling amplification sensor integrated with catalytic hairpin assembly (CHA) to achieve high sensitivity for fluorescent detection of ATP. The association of the target ATP with the aptamer beacons causes the allosteric structure switching of the aptamer beacons to expose the toehold regions, which hybridize with and unfold the fluorescently quenched hairpin signal probes (HP1) to recycle the target ATP and to trigger CHA between HP1 and the secondary hairpin probes (HP2) to form HP1/HP2 duplexes. Due to the recycling amplification, the presence of ATP leads to the formation of many HP1/HP2 duplexes, generating dramatically amplified fluorescent signals for sensitive detection of ATP. Under optimal experimental conditions, our sensor linearly responds to ATP in the range from 25 to 600nM with a calculated detection limit of 8.2nM. Furthermore, the sensor shows a high selectivity and can also be used to detect ATP in human serums to realize its application for real samples. With the distinct advantage of significant signal amplification without the involvement of any nanomaterial and enzyme, the developed sensor thus holds great potential for simple and sensitive detection of different small molecules and proteins.
异常浓度的 ATP 与许多疾病和癌症有关，因此定量检测 ATP 对于疾病的诊断和预后具有重要意义。在本工作中，我们报告了一种新的双重循环放大传感器，该传感器与催化发夹组装（CHA）集成，可实现对 ATP 的荧光检测的高灵敏度。靶标 ATP 与适体信标结合会导致适体信标的变构结构切换，从而暴露出适体信标的连接区域，该连接区域与荧光猝灭发夹信号探针（HP1）杂交并展开，以循环利用目标 ATP，并触发 HP1 与二级发夹探针（HP2）之间的 CHA 形成 HP1/HP2 双链体。由于循环放大，ATP 的存在导致形成许多 HP1/HP2 双链体，从而产生用于敏感检测 ATP 的明显放大的荧光信号。在最佳实验条件下，我们的传感器对 25 至 600nM 范围内的 ATP 呈线性响应，计算出的检测限为 8.2nM。此外，该传感器具有高选择性，还可用于检测人血清中的 ATP，以实现其对实际样品的应用。由于具有无需任何纳米材料和酶参与即可实现显著信号放大的独特优势，因此所开发的传感器在用于不同小分子和蛋白质的简单和灵敏检测方面具有很大的潜力。
