Niu Panpan, Jiang Junfeng, Liu Kun, Wang Shuang, Jing Jianying, Xu Tianhua, Wang Tong, Liu Yize, Liu Tiegen
School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China.
School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China; Key Laboratory of Opto-electronics Information Technology (Tianjin University), Key Laboratory of Micro Opto-electro Mechanical System Technology (Tianjin University), Ministry of Education, Tianjin, 300072, China; Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin, 300072, China.
Biosens Bioelectron. 2022 Jul 15;208:114238. doi: 10.1016/j.bios.2022.114238. Epub 2022 Mar 31.
Cardiac troponin I (cTnI) plays an important role in emergency diagnosis of cardiovascular diseases, which exists predominately in the form of cardiac troponin I-C (cTnI-C) complex. We proposed a fiber-integrated optofluidic chip immunosensor with time-delay-dispersion based microwave photonic analyzer (MPA) for cTnI-C detection. The whispering gallery mode (WGM) fiber probe was fabricated by embedding a polydopamine functionalized hollow glass microsphere (HGMS) into the etched capillary-fiber structure, and the WGMs could be excited through the efficient coupling between the thin-wall capillary and the HGMS. The reflective WGM optofluidic chip functioned as a wavelength tuner to construct fiber ring laser cavity, whose laser output wavelength was cTnI-C concentration-dependent. The tiny wavelength variation of sensing laser was converted into a radio-frequency (RF) response, which was retrieved by measuring the change of RF-domain free spectrum range (FSR) in time-delay-dispersion based MPA, and the quantitative detection of cTnI-C complex can be achieved with high resolution. Experimental results show that this immunosensor had a limit of detection (LOD) of 0.59 ng/mL, and a detection resolution of 1.2 fg/mL. The relative resolving power was 10-10-fold higher than that of others optical fiber cTnI biosensors. The proposed fiber-integrated optofluidic chip provides an innovative lab-on-chip diagnostic tool for myocardial damage.
心肌肌钙蛋白I（cTnI）在心血管疾病的急诊诊断中发挥着重要作用，其主要以心肌肌钙蛋白I-C（cTnI-C）复合物的形式存在。我们提出了一种基于时延色散的微波光子分析仪（MPA）的光纤集成光流体芯片免疫传感器，用于检测cTnI-C。通过将聚多巴胺功能化的空心玻璃微球（HGMS）嵌入蚀刻的毛细管-光纤结构中来制造回音壁模式（WGM）光纤探头，并且可以通过薄壁毛细管与HGMS之间的有效耦合来激发WGM。反射式WGM光流体芯片用作波长调谐器以构建光纤环形激光腔，其激光输出波长与cTnI-C浓度相关。传感激光的微小波长变化被转换为射频（RF）响应，通过在基于时延色散的MPA中测量RF域自由光谱范围（FSR）的变化来获取该响应，并且可以高分辨率实现cTnI-C复合物的定量检测。实验结果表明，这种免疫传感器的检测限（LOD）为0.59 ng/mL，检测分辨率为1.2 fg/mL。相对分辨能力比其他光纤cTnI生物传感器高10^-10倍。所提出的光纤集成光流体芯片为心肌损伤提供了一种创新的芯片实验室诊断工具。
