Department of Chemistry & Institute of Biomedicine Science & State Key Laboratory of Molecular Engineering of Polymers & Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, 2005 Songhu Road, Shanghai, 200438, P. R. China.
College of Materials Science and Engineering & Institute of Smart Biomedical Materials, Zhejiang Sci-Tech University, Hangzhou, 310018, P. R. China.
Small. 2022 Apr;18(14):e2107963. doi: 10.1002/smll.202107963. Epub 2022 Feb 19.
Temperature as a typical parameter, which influences the status of living creatures, is essential to life activities and indicates the initial cellular activities. In recent years, the rapid development of nanotechnology provides a new tool for studying temperature variation at the micro- or nano-scales. In this study, an important phenomenon is observed at the cell level using luminescent probes to explore intracellular temperature changes, based on Yb-Er doping nanoparticles with special upconversion readout mode and intensity ratio signals (I and I ). Further optimization of this four-layer core-shell ratio nanothermometer endows it with remarkable characteristics: super photostability, sensitivity, and protection owing to the shell. Thus this kind of thermal probe has the property of anti-interference to the complex chemical environment, responding exclusively to temperature, when it is used in liquid and cells to reflect external temperature changes at the nanoscale. The intracellular temperature of living RAW and CAOV3 cells are observed to have a resistance mechanism to external stimuli and approach a more favorable temperature, especially for CAOV3 cells with good heat resistance, with the intracellular temperature 4.8 °C higher than incubated medium under 5 °C environment, and 4.4 °C lower than the medium under 60 °C environment.
温度作为影响生物生存状态的典型参数，对生命活动至关重要，它反映了细胞的初始活动。近年来，纳米技术的飞速发展为研究微观和纳米尺度下的温度变化提供了新的工具。在这项研究中，使用发光探针观察到细胞水平上的一个重要现象，以探索细胞内温度的变化，其基础是具有特殊上转换读出模式和强度比信号（I 和 I ）的 Yb-Er 掺杂纳米粒子。进一步优化这种四层核壳比纳米温度计赋予了它显著的特性：由于外壳的存在，具有超级光稳定性、灵敏度和保护性能。因此，当这种热探针用于液体和细胞中时，它具有抗复杂化学环境干扰的特性，仅响应温度，以反映纳米级外部温度变化。观察到活 RAW 和 CAOV3 细胞的细胞内温度具有对外界刺激的抵抗机制，并接近更有利的温度，特别是对于具有良好耐热性的 CAOV3 细胞，在 5°C 环境下，其细胞内温度比孵育介质高 4.8°C，在 60°C 环境下比介质低 4.4°C。
