水凝胶波导探针的制备及对罗丹明B的超高灵敏检测  

Preparation of hydrogel waveguide probe and ultrasensitive detection of rhodamine B

作　　者：罗洪 蔡斌[1] LUO Hong;CAI Bin(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093

出　　处：《光学仪器》2024年第2期1-6,共6页Optical Instruments

摘　　要：波导型倏逝波传感器依赖于待测物与倏逝场的相互作用,其检测能力受制于倏逝波的强弱。一般而言,波导的倏逝波强度在内部传输光中占比很低,因此传感器灵敏度受到很大限制。提出的一种基于水凝胶聚合物的波导探针可以克服上述缺点。水凝胶具有的三维网状结构,可以方便待测物渗入波导内部,因此可以利用局域在波导内部的传输光进行探测,大幅提高探测光的利用效率。此外,实验通过其他聚合物单体的添加成功抑制了水凝胶波导遇水溶胀变形带来的额外光损。由于纯水凝胶制备的波导在吸水溶胀后会导致变形,从而带来额外的光损耗,因此除水凝胶之外还需掺入其他聚合物以维持波导的基本形状。实验表明,该水凝胶聚合物波导传感器对罗丹明B水溶液的吸收检测极限为1.0×10^(−9) g/mL,荧光检测极限为1.0×10^(−19)g/mL。相比于其他波导型倏逝波传感器,荧光检测极限提高了约7个数量级。该水凝胶聚合物波导传感器制备方法简单,成本低廉,可适应性高,灵敏度高,在医疗及环境监测等多个领域都有着广泛的应用前景。The waveguide-type evanescent wave sensor depends on the interaction between the analyte and the evanescent field,and its detectability is determined by the intensity of evanescent wave.However,the intensity of evanescent waves in waveguides is relatively low compared to the amount of light that propagating in the waveguide core.As a result,the sensitivity of sensors is greatly limited.In this paper,we propose a waveguide probe based on hydrogel polymer to overcome this issue.The three-dimensional network structure of the hydrogel facilitates the penetration of the analyte into the waveguide,allowing the transmitted light localized inside the waveguide to be used for detection.This significantly improves the utilization efficiency of the transmission light.In addition,the experiment successfully suppressed the additional optical losses caused by water-induced swelling deformation of the hydrogel waveguide by adding other polymer monomers.Since the waveguide prepared from pure hydrogel causes deformation upon water absorption and swelling,which brings additional light loss,other polymers in addition to hydrogel are doped to maintain the basic shape of the waveguide.The experiment results show that the hydrogel polymer waveguide sensor has an absorption detection limit of is 1.0×10^(−9) g/mL for rhodamine B aqueous solution and 1.0×10^(−19)g/mL for fluorescence,which is about 7 orders of magnitude higher than that of other waveguide-based evanescent wave sensors.The hydrogel polymer waveguide sensor has the advantages of simple preparation,low cost,high adaptability and excellent sensitivity making it a promising candidate for various,applications,such as medical treatment and environmental monitoring.

关 键 词：水凝胶 聚合物波导 荧光光谱 检测极限 

分 类 号：O439[机械工程—光学工程]