Shanghai State Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, East China Normal University , Dongchuan Road 500, Shanghai 200241, China.
Anal Chem. 2016 Dec 20;88(24):12294-12302. doi: 10.1021/acs.analchem.6b03470. Epub 2016 Nov 28.
Intracellular pH undertakes critical functions in the formation of a proton gradient and electrochemical potential that drives the adenosine triphosphate synthesis. It is also involved in various metabolic processes occurring in mitochondria, such as the generation of reactive oxygen species, calcium regulation, as well as the triggering of cell proliferation and apoptosis. Meanwhile, the aberrant accumulation of O within mitochondria is frequently intertwined with mitochondrial dysfunction and disease development. To disentangle the complicated inter-relationship between pH and O in the signal transduction and homeostasis in mitochondria, herein we developed a mitochondria-targeted single fluorescent probe for simultaneous sensing and imaging of pH and O in mitochondria. CdSe/ZnS quantum dots encapsulated in silica shell was designed as an inner reference element for providing a built-in correction, as well as employed as a carrier to assemble the responsive elements for O and pH, together with mitochondria-targeted molecule. The developed nanosensor demonstrated high accuracy and selectivity for pH and O sensing, against other ROS, metal ions, and amino acids. The remarkable analytical performance of the present nanosensor, as well as good biocompatibility, established an accurate and selective approach for real-time imaging and biosensing of O and pH in mitochondria of live cells.
细胞内 pH 值在质子梯度和电化学势的形成中起着关键作用，这种质子梯度和电化学势驱动着三磷酸腺苷的合成。它还参与线粒体中发生的各种代谢过程，如活性氧物种的产生、钙调节以及细胞增殖和凋亡的触发。同时，线粒体中 O 的异常积累常常与线粒体功能障碍和疾病的发展交织在一起。为了理清 pH 值和 O 在信号转导和线粒体内稳态中的复杂相互关系，我们在这里开发了一种线粒体靶向的单荧光探针，用于同时检测和成像线粒体中的 pH 值和 O。CdSe/ZnS 量子点被包裹在二氧化硅壳中，作为内参元素，提供内置校正，同时也作为载体，组装用于 O 和 pH 值的响应元件，以及线粒体靶向分子。所开发的纳米传感器对 pH 值和 O 检测具有高准确性和选择性，可抵抗其他 ROS、金属离子和氨基酸。这种纳米传感器具有出色的分析性能和良好的生物相容性，为活细胞中线粒体中 O 和 pH 值的实时成像和生物传感建立了一种准确和选择性的方法。
