Institute of Nanophotonics, Jinan University, Guangzhou, 511443, China.
Department of Physiology, School of Medicine, Jinan University, Guangzhou, 510632, China.
Adv Sci (Weinh). 2022 Jan;9(3):e2103354. doi: 10.1002/advs.202103354. Epub 2021 Nov 23.
Intracellular thermometry provides important information about the physiological activity of single cells and has been implemented using diverse temperature-sensitive materials as nanoprobes. However, measuring the temperature of specific organelles or subcellular structures is challenging because it requires precise positioning of the nanoprobes. Here, it is shown that dispersed fluorescent nanodiamonds (FNDs) endocytosed in living cells can be aggregated into microspheres using optical forces and used as intracellular temperature probes. The aggregation of the FNDs and electromagnetic resonance between individual nanodiamonds in the microspheres lead to a sevenfold intensity enhancement of 546-nm laser excitation. With the assistance of a scanning optical tweezing system, the FND microspheres can be precisely patterned and positioned within the cells. By measuring the fluorescence spectra of the microspheres, the temperatures at different locations within the cells are detected. The method provides an approach to the constructing and positioning of nanoprobes in an intracellular manner, which has potential applications in high-precision and flexible single-cell analysis.
细胞内测温提供了关于单个细胞生理活动的重要信息，已使用各种温度敏感材料作为纳米探针来实现。然而，测量特定细胞器或亚细胞结构的温度具有挑战性，因为这需要纳米探针的精确定位。本文展示了可以用光镊将活细胞内吞的分散荧光纳米金刚石（FND）聚集成微球，并用作细胞内温度探针。FND 的聚集和微球中单个纳米金刚石之间的电磁共振导致 546nm 激光激发的强度增强了七倍。在扫描光学镊子系统的辅助下，可以精确地对 FND 微球进行图案化和定位。通过测量微球的荧光光谱，可以检测细胞内不同位置的温度。该方法提供了一种在细胞内构建和定位纳米探针的方法，在高精度和灵活的单细胞分析中具有潜在应用。
