Application Of Optic Fiber SPR Sensor In Biological Immunology

With the development of life sciences and fiber SPR technology,biosensors based on fiber SPR sensors have become increasingly important in biosensing with the unique advantages of label-free,small volume,low cost,and enabling distributed and remote detection.Its role in the analysis of the interactions between protein macromolecules,DNA and protein molecules,DNA intermolecular interactions,or antigen-antibody reaction monitoring has attracted widespread attention.In this paper,optical fiber SPR sensor has been applied to the study of biological immunology.The dopamine modification method has been used to immobilize antibodies on the sensor surface.By the antigen-antibody specific reaction,it can realize online,real-time,in situ and highly sensitive detection of human CRP.There is a wide range of applications in the field of food analysis,medical testing and life sciences.The main work is as follows:1.A multimode fiber SPR sensor is studied.The fiber SPR biosensing system is set up firstly.The temperature characteristics of the fiber SPR sensor in PBS buffer have been explored.When immersed in solution with a different refraction index,the SPR spectral changes have be observed.The performance of sensor for refractive index sensing is studied.The consistency and stability of the optical fiber SPR biosensor are measured by continuous real-time monitoring under different solution and concentration.2.The research on dopamine-modified optical fiber SPR immunosensors is carried out.The mechanism of dopamine modification is summarized,and the modification conditions for specific detection of CRP are preliminarily explored.The influence of CRP-specific detection membrane selection on the detection effect is investigated,and the time for the cross-linked CRP-specific detection membrane is initially explored.Finally,the optimal conditions of the concentration of dopamine solution and the time for dopamine surface modification on the sensor are also investigated experimentally.3.Dopamine-modified optical fiber SPR biosensor is used to for specific detection of CRP.The sensor performance affected by the time for CRP monoclonal antibody cross-linking and CRP detection has been explored.Experimental results show that the sensor is sensitive to the specific binding reaction between CRP monoclonal antibody and CRP.The sensor has a good linear response to the logarithmic concentration of CRP,and the detection limit reaches 0.1 μg/ml.4.The optical fiber SPR immunosensor based on the disulfide bond reduction method has been developed.The mechanism of disulfide bond reduction has been introduced.To optimize the conditions of disulfide bond reduction reaction,the selective disulfide bond breaking between antibody chains has been achieved,and the performance of antibody fragments immobilized on gold film surface of sensor has been explored.The ability to specifically recognise antigens after immobilization has also been explored.