Xuegang Li,Pengqi Gong,Xue Zhou,Shankun Wang,Yingxuan Liu,Yanan Zhang,Linh V. Nguyen,Stephen C. Warren-Smith,Yong Zhao
An advanced multi-parameter optical fiber sensing technology for EGFR gene detection based on DNA hybridization technology is demonstrated in this paper. For traditional DNA hybridization detection methods, temperature and pH compensation can not be realized or need multiple sensor probes. However, the multi-parameter detection technology we proposed can simultaneously detect complementary DNA, temperature and pH based on a single optical fiber probe. In this scheme, three optical signals including dual surface plasmon resonance signal (SPR) and Mach-Zehnder interference signal (MZI) are excited by binding the probe DNA sequence and pH-sensitive material with the optical fiber sensor. The paper proposes the first research to achieve simultaneous excitation of dual SPR signal and Mach-Zehnder interference signal in a single fiber and used for three-parameter detection. Three optical signals have different sensitivities to the three variables. From a mathematical point of view, the unique solutions of exon-20 concentration, temperature and pH can be obtained by analyzing the three optical signals. The experimental results show that the exon-20 sensitivity of the sensor can reach 0.07 nm nM −1 , and the limit of detection is 3.27 nM. The designed sensor gives a fast response, high sensitivity, and low detection limit, which is important for the field of DNA hybridization research and for solving the problems of biosensor susceptibility to temperature and pH.
A novel DNA hybridization optical fiber sensor with temperature and pH compensation for detecting a common lung cancer gene of epidermal growth factor receptor (EGFR) gene was demonstrated in this paper. The paper proposes the first research to achieve dual surface plasmon resonance (SPR) in an Fiber Bragg grating (FBG) and implement a three-parameter detection of DNA sequence , temperature and pH using a single fiber. Probe DNA sequences (pDNA) and PAA/CS, a pH-sensitive material, are immobilized on the sensor surface for EGFR gene exon-20 detection and temperature and pH monitoring simultaneously. The effectiveness of this functionalized method has been proved by using an atomic force microscope (AFM) and scanning electron microscope (SEM). The limit of detection (LOD) of EGFR gene was experimentally verified to 13.5 nM. The advantages of fast response, high sensitivity, label free, plug in, low LOD and three-parameter detection demonstrated by this sensor in the experiment are important for the field of DNA hybridization research and solving the problems of biosensor susceptibility to temperature and pH.