Hydrogel Fluorescence Microsensor with Fluorescence Recovery for Prolonged Stable Temperature Measurements
Hydrogel Fluorescence Microsensor with Fluorescence Recovery for Prolonged Stable Temperature Measurements
复制标题
DOI：
10.3390/s19235247
复制
发表时间：
2019-12-01
期刊：
影响因子：
3.9
通讯作者：
Arai, Fumihito
中科院分区：
文献类型：
--
作者：
Hashim, Hairulazwan;Maruyama, Hisataka;Arai, Fumihito
本工作描述了一种用于长时间稳定温度测量的水凝胶荧光微传感器。使用微传感器进行温度测量有可能提供有关细胞、组织和培养环境的信息，使用荧光染料进行光学测量是一种很有前途的微传感方法。然而，基于荧光染料荧光强度的传统测量方法在长时间内实现稳定的测量是具有挑战性的，因为受激发的荧光染料分子在暴露于光下会被漂白。光漂白引起的荧光强度下降导致测量误差。本文提出了一种基于荧光染料在水凝胶微传感器内部扩散的光漂白补偿方法。影响水凝胶微传感器补偿的因素有测量间隔时间、材料、光引发剂浓度和荧光微传感器的组成。通过比较直径均为20 μ m的聚苯乙烯荧光微传感器和水凝胶荧光微传感器来评估这些因素。由9%聚乙二醇二丙烯酸酯（PEGDA） 575和2%光引发剂制成的水凝胶荧光微传感器在暴露后显示出出色的荧光强度稳定性（100次测量重复后与初始荧光差的标准偏差：在1%以内）。研究了微传感器尺寸对荧光强度稳定性的影响。水凝胶荧光微传感器的尺寸大于共聚焦显微镜轴向分辨率确定的测量区域，在900次重复测量后，荧光强度略有下降，下降幅度在3%以内。用热电堆和水凝胶荧光微传感器测量了微室中去离子水的温度5400 s。结果表明，两种传感器的最大误差和误差标准差分别为0.5℃和0.3℃，验证了所提方法的有效性。
This work describes a hydrogel fluorescence microsensor for prolonged stable temperature measurements. Temperature measurement using microsensors has the potential to provide information about cells, tissues, and the culture environment, with optical measurement using a fluorescent dye being a promising microsensing approach. However, it is challenging to achieve stable measurements over prolonged periods with conventional measurement methods based on the fluorescence intensity of fluorescent dye because the excited fluorescent dye molecules are bleached by the exposure to light. The decrease in fluorescence intensity induced by photobleaching causes measurement errors. In this work, a photobleaching compensation method based on the diffusion of fluorescent dye inside a hydrogel microsensor is proposed. The factors that influence compensation in the hydrogel microsensor system are the interval time between measurements, material, concentration of photo initiator, and the composition of the fluorescence microsensor. These factors were evaluated by comparing a polystyrene fluorescence microsensor and a hydrogel fluorescence microsensor, both with diameters of 20 mu m. The hydrogel fluorescence microsensor made from 9% poly (ethylene glycol) diacrylate (PEGDA) 575 and 2% photo initiator showed excellent fluorescence intensity stability after exposure (standard deviation of difference from initial fluorescence after 100 measurement repetitions: within 1%). The effect of microsensor size on the stability of the fluorescence intensity was also evaluated. The hydrogel fluorescence microsensors, with sizes greater than the measurement area determined by the axial resolution of the confocal microscope, showed a small decrease in fluorescence intensity, within 3%, after 900 measurement repetitions. The temperature of deionized water in a microchamber was measured for 5400 s using both a thermopile and the hydrogel fluorescence microsensor. The results showed that the maximum error and standard deviation of error between these two sensors were 0.5 degrees C and 0.3 degrees C, respectively, confirming the effectiveness of the proposed method.