Simulation Reseach On The Lable-free Biosensor Characteristic Of The MOF-LPG

Label-free optical fiber biosensor has the advantages of simple structure, easyoperation and high sensitivity, so it becomes an important part of the biosensorsresearch, and has received wide attentions. As a new type of special optical fiber,micro-structured optical fiber has completely different structure and opticaltransmission characteristic compared with single mode fiber, especially flexibility onthe structure design. So, it has developed a new field for production and application ofoptical fiber devices. The emergence of the micro-structured optical fiber gratingsprovides a new opportunity for label-free optical fiber biosensor’s research, and theunique advantages make the fiber an important research value for improving thesensing sensitivity.This paper introduces the research situation of the label-free opticalfiber biosensor in recent years in detail, and simulates the refractive sensingcharacteristic and biological film thickness sensing characteristic of themicro-structured optical fiber gratings. The main contents include:First, the necessity of research and the status of theory, fabrication andapplication on label-free optical fiber biosensor are introduced. And elaborate thetheoretical basis and methods of micro-structured optical fiber’s transmission modedistribution and its gratings’ reflection spectrum or transmission spectrum.Next, the refractive index, and the biological film thickness sensitivity ofgrapefruit micro-structured optical fiber cascaded grating are studied deeply. Thewavelength difference method is promoted to detect the biological film thickness.Once more, the sensing properties of grapefruit photonic crystal fiber long-periodgrating whose cladding is corroded but its air holes are not broken is analyzedtheoretically based on the finite element method and coupled mode theory. Bycorroding the cladding of grapefruit photonic crystal fiber, its refractive index sensingcharacteristics and the bio-film thickness sensing characteristics is analyzed.Finally, designs a new type of micro-structured optical fiber whose cladding hasthree big air hole. And studies its transmission mode distribution and its gratings’ transmission spectrum. Its refractive index sensitivity is analyzed and its refractiveindex sensitivity is much higher than grapefruit photonic crystal fiber gratings.