Department of Chemistry, Fudan University, 200433, Shanghai, People's Republic of China.
Key Laboratory of Fine Chemicals, Department of Chemistry, Dalian University of Technology, Dalian, 116012, People's Republic of China.
Mikrochim Acta. 2018 Nov 6;185(12):533. doi: 10.1007/s00604-018-3040-y.
Lysosomal pH and temperature are two crucial physiological parameters that are involved in regulating intracellular homeostasis, and their precise measurements are extremely important in understanding this process and diseases diagnosis. A lysosome-targeting nanosensor has been designed for simultaneous imaging of pH values and temperature in HeLa cells. Three dyes were covalently immobilized either inside or on silica nanoparticles. The nanosensors have an average diameter of 95 nm. The large surface area of these nanomaterials provides abundant sites for multi-functionality. The surface of nanosensors has been modified with positively-charged amino groups in order to facilitate endocytosis and targeting lysosome. Fluorescein is used as the indicator probe for pH measurement, rhodamine B is the probe for temperature, and a europium complex acts as the reference dye. The dual nanosensor responds to pH values in the range from 3.0 to 9.0, and to temperature in the range from 20 to 60 °C. Owing to its good biocompatibility and good sensitivity, the dual nanosensor has been used to monitor changes in local pH values and temperature in the lysosome of HeLa cells. Graphical abstract A dual nanosensor for simultaneously imaging of pH values and temperature inside the lysosome of HeLa cells was constructed by labelling three luminophores in/on silica nanoparticles. It shows high sensitivity and selectivity, good photostability, and good biocompatibility.
溶酶体的 pH 值和温度是两个关键的生理参数，它们参与调节细胞内的动态平衡，对其进行精确测量对于理解这一过程和疾病诊断非常重要。本研究设计了一种用于同时成像 HeLa 细胞溶酶体 pH 值和温度的溶酶体靶向纳米传感器。三种染料通过共价键固定在二氧化硅纳米粒子的内部或表面。纳米传感器的平均直径为 95nm。这些纳米材料的大表面积为多功能化提供了丰富的位点。纳米传感器的表面经过正电荷氨基基团修饰，以促进内吞作用和靶向溶酶体。荧光素被用作 pH 值测量的指示剂探针，若丹明 B 是温度探针，铕配合物作为参考染料。双纳米传感器对 pH 值范围为 3.0 至 9.0、温度范围为 20 至 60°C 的响应。由于其良好的生物相容性和高灵敏度，双纳米传感器已用于监测 HeLa 细胞溶酶体中局部 pH 值和温度的变化。
