Label-Free Detection of Cancer Biomarkers Using an In-Line Taper Fiber-Optic Interferometer and a Fiber Bragg Grating

Dandan Sun; Yang Ran; Guanjun Wang

doi:10.3390/s17112559

Label-Free Detection of Cancer Biomarkers Using an In-Line Taper Fiber-Optic Interferometer and a Fiber Bragg Grating

Sensors (Basel). 2017 Nov 6;17(11):2559. doi: 10.3390/s17112559.

Authors

Dandan Sun¹, Yang Ran², Guanjun Wang³

Affiliations

¹ College of Physics and Electronic Engineering, Shanxi University, Taiyuan 030006, China. sundd@sxu.edu.cn.
² Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China. tranyang@jnu.edu.cn.
³ School of Information and Communication Engineering, North University of China, Taiyuan 030051, China. wangguanjun@nuc.edu.cn.

Abstract

A compact and label-free optical fiber sensor based on a taper interferometer cascaded with a fiber Bragg grating (FBG) is proposed and experimentally demonstrated for detection of a breast cancer biomarker (HER2). The tapered fiber-optic interferometer is extremely sensitive to the ambient refractive index (RI). In addition, being insensitive to the RI variation, the FBG can be applied as a temperature thermometer due to its independent response to the temperature. Surface functionalization to the sensor is carried out to achieve specific targeting of the unlabeled biomarkers. The result shows that the proposed sensor presents a low limit-of-detection (LOD) of 2 ng/mL, enabling its potentials of application in early diagnosis on the breast cancer.

Keywords: FBG; cancer biomarker; fiber taper interferometer; optical biosensor.