State Key Laboratory of Chemo-Biosensing & Chemometrics, College of Chemistry & Chemical Engineering , Hunan University , Changsha 410082 , China.
Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Hunan Province College Key Laboratory of QSAR/QSPR, School of Chemistry and Chemical Engineering, Hunan Provincial Key Lab of Advanced Materials for New Energy Storage and Conversion , Hunan University of Science and Technology , Xiangtan , Hunan 411201 , China.
ACS Sens. 2018 Dec 28;3(12):2526-2531. doi: 10.1021/acssensors.8b00670. Epub 2018 Dec 5.
We develop a novel amplified split aptamer sensor for highly sensitive detection and imaging of small molecules in living cells by using cationic block copolymer nanoparticles (BCNs) with entrapped fluorescent conjugated polymer as a delivery agent. The design of a split aptamer as the initiator of hybridization chain reaction (HCR) affords the possibility of enhancing the signal-to-background ratio and thus allows high-contrast imaging for small molecules with relatively weak interactions with their aptamers. The novel design of using fluorescent cationic BCNs as the nanocarrier enables efficient and self-tracking transfection of DNA probes. Results reveal that BCNs exhibit high fluorescence brightness allowing direct tracking of the delivery location. The developed amplified split aptamer sensor is shown to have high sensitivity and selectivity for in vitro quantitative detection of adenosine triphosphate (ATP) with a detection limit of 30 nM. Live cell studies show that the sensor provides a "signal on" approach for specific, high-contrast imaging of ATP. The DNA sensor based HCR system may provide a new generally applicable platform for detection and imaging of low-abundance biomarkers.
我们开发了一种新型的扩增分裂适体传感器，通过使用阳离子嵌段共聚物纳米粒子（BCN）作为递送剂，将其包裹的荧光共轭聚合物作为荧光探针，用于在活细胞中对小分子进行高灵敏度检测和成像。分裂适体作为杂交链式反应（HCR）的引发剂的设计提供了增强信号背景比的可能性，从而允许对与适体相互作用较弱的小分子进行高对比度成像。使用荧光阳离子 BCN 作为纳米载体的新颖设计能够有效地进行 DNA 探针的自我跟踪转染。结果表明，BCN 具有高荧光亮度，允许直接跟踪递送位置。所开发的扩增分裂适体传感器对三磷酸腺苷（ATP）的体外定量检测具有高灵敏度和选择性，检测限为 30 nM。活细胞研究表明，该传感器提供了一种“信号开启”的方法，用于对 ATP 进行特异性、高对比度成像。基于 HCR 系统的 DNA 传感器可能为低丰度生物标志物的检测和成像提供一个新的通用平台。
