Development of an optical microfiber immunosensor for prostate specific antigen analysis using a high-order-diffraction long period grating
Peng Xiao, Zhen Sun, Yan Huang, Wenfu Lin, Yuchen Ge, Ruitao Xiao, Kaqiang Li, Zhenru Li, Hanglin Lu, Mingjin Yang, Lili Liang, Li‐Peng Sun, Yang Ran, Jie Li, Bai‐Ou Guan
Abstract
Fiber-optic biosensors are of great interest to many bio/chemical sensing applications. In this study, we demonstrate a high-order-diffraction long period grating (HOD-LPG) for the detection of prostate specific antigen (PSA). A HOD-LPG with a period number of less than ten and an elongated grating pitch could realize a temperature-insensitive and bending-independent biosensor. The bio-functionalized HOD-LPG was capable of detecting PSA in phosphate buffered saline with concentrations ranging from 5 to 500 ng/ml and exhibited excellent specificity. A limit of detection of 9.9 ng/ml was achieved, which is promising for analysis of the prostate specific antigen.