Real-time temperature monitoring inside living organisms provides a direct measure of their biological activities. However, it is challenging to reduce the size of biocompatible thermometers down to submicrometers, despite their potential applications for the thermal imaging of subtissue structures with single-cell resolution. Here, using quantum nanothermometers based on optically accessible electron spins in nanodiamonds, we demonstrate in vivo real-time temperature monitoring inside Caenorhabditis elegans worms. We developed a microscope system that integrates a quick-docking sample chamber, particle tracking, and an error correction filter for temperature monitoring of mobile nanodiamonds inside live adult worms with a precision of ±0.22°C. With this system, we determined temperature increases based on the worms’ thermogenic responses during the chemical stimuli of mitochondrial uncouplers. Our technique demonstrates the submicrometer localization of temperature information in living animals and direct identification of their pharmacological thermogenesis, which may allow for quantification of their biological activities based on temperature.

生物体内的实时温度监测提供了对其生物活动的直接测量。然而，将生物相容性温度计的尺寸减小到亚微米是具有挑战性的，尽管它们在具有单细胞分辨率的亚组织结构的热成像方面具有潜在的应用。在这里，我们使用基于纳米金刚石中光学可访问电子自旋的量子纳米温度计，展示了秀丽隐杆线虫体内的实时温度监测蠕虫。我们开发了一种显微镜系统，该系统集成了快速对接样品室、粒子跟踪和误差校正过滤器，用于对活成虫体内的移动纳米金刚石进行温度监测，精度为 ±0.22°C。使用这个系统，我们根据线虫在线粒体解偶联剂的化学刺激过程中的产热反应确定了温度升高。我们的技术展示了活体动物温度信息的亚微米定位和直接识别它们的药理产热，这可能允许基于温度量化它们的生物活性。