光学 精密工程, 2020, 28 (2): 296, 网络出版: 2020-05-27
改性石墨烯包覆光纤的马赫-曾德尔大肠杆菌传感器
Escherichia coli fiber sensor based on modified graphene coated fiber Mach-Zehnder interference
光纤传感器 马赫-曾德尔干涉 表面改性 石墨烯 大肠杆菌 optical fiber sensor Mach-Zehnder interference surface modification graphene Escherichia coli
摘要
针对日益严峻的食品安全问题, 特别是食源性致病菌的快速检测, 本文提出一种基于表面改性石墨烯粗锥型马赫-曾德尔干涉结构的光纤大肠杆菌传感器。首先, 截取一根4 cm的实心光子晶体光纤, 两端分别与两根单模光纤进行粗锥熔接, 形成基于马赫-曾德尔干涉原理的传感结构; 接着, 制备一种表面改性石墨烯敏感材料, 将它涂覆在实心光子晶体光纤的表面, 使传感器对大肠杆菌溶液有较高的灵敏度; 最后, 将上述传感器置于水槽中, 以此检测大肠杆菌溶液浓度。实验结果表明, 在大肠杆菌溶液浓度为50~600 cfu/mL内, 随着菌液的浓度增大, 传感器的干涉光谱发生了明显的蓝移, 灵敏度为3.43 pm/(cfu·mL-1), 菌液浓度与波长偏移的线性度为0.956 49, 检测限为67.18 cfu/mL, 响应时间为15 s。该传感器成本低、体积小、响应时间快, 适用于低浓度大肠杆菌浓度的快速检测。
Abstract
To solve increasingly serious food safety problems, especially the rapid detection of food-borne viruses, an E. coli sensor based on the surface-modified graphene enlarged-cone Mach-Zehnder interference structure was proposed in this study. First, a 4 cm solid photonic crystal fiber was intercepted and coarsely fused with two single-mode fibers to form an interference structure based on the Mach-Zehnder principle. Next, surface-modified graphene sensitive material was prepared. The modified graphene, coated on the surface of the solid photonic crystal fiber, allowed the sensor to have a higher sensitivity to E. coli solutions. Finally, the above sensor is placed in a water tank to detect the concentration of the E. coli. The experimental results show that the interference spectrum of the sensor has a significant blue shift with a sensitivity of 3.43 pm/(cfu·mL-1) in the range of 50-600 cfu/mL of the E. coli solution. The linearity between the bacterial concentration and wavelength shift is 0.956 49, detection limit is 67.18 cfu/ml, and response time is 15 s. The sensor has low cost, small volume, fast response time, and is suitable for the rapid detection of low concentration E. coli.
彭志清, 廖杰, 李玉洁, 冯文林, 杨晓占. 改性石墨烯包覆光纤的马赫-曾德尔大肠杆菌传感器[J]. 光学 精密工程, 2020, 28(2): 296. PENG Zhi-qing, LIAO Jie, LI Yu-jie, FENG Wen-lin, YANG Xiao-zhan. Escherichia coli fiber sensor based on modified graphene coated fiber Mach-Zehnder interference[J]. Optics and Precision Engineering, 2020, 28(2): 296.