Fluorescence anisotropy, a technique to study the folding state of proteins or affinity of ligands, is used in this present work as a temperature sensor, to measure the microfluidic temperature field, by adding fluorophore in the liquid. Fluorescein was used as a temperature-sensing probe, while glycerol–aq. ammonia solution was used as a working fluid. Fluorescence anisotropy of fluorescein was measured by varying various parameters. Apart from this, a comparison of fluorescence anisotropy and fluorescence intensity is also performed to demonstrate the validity of anisotropy to be applied in a microfluidic field with non-uniform liquid thickness. Viscosity dependence and temperature dependence on the anisotropy are also clarified; the results indicate an appropriate selection of relation between molecule size and viscosity is important to obtain a large temperature coefficient in anisotropy. Furthermore, a practical calibration procedure of the apparatus constant is proposed. In addition, the potential of temperature imaging is confirmed by the measurement of temperature distribution under focused laser heating.

中文翻译：

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使用荧光素的荧光各向异性作为温度传感分子探针

荧光各向异性是一种研究蛋白质折叠状态或配体亲和力的技术，在本工作中用作温度传感器，通过在液体中添加荧光团来测量微流体温度场。荧光素用作温度传感探针，而甘油-水溶液。氨溶液用作工作流体。通过改变各种参数来测量荧光素的荧光各向异性。除此之外，还进行了荧光各向异性和荧光强度的比较，以证明各向异性在具有非均匀液体厚度的微流体场中的有效性。还阐明了对各向异性的粘度依赖性和温度依赖性；the results indicate an appropriate selection of relation between molecule size and viscosity is important to obtain a large temperature coefficient in anisotropy. 此外，提出了仪器常数的实用校准程序。此外，通过测量聚焦激光加热下的温度分布，证实了温度成像的潜力。