Research On Surface Plasmon Resonance-Fluorescence Dual-Mode Image Detection Method And System

As the conventional method in the field of biological detection,surface plasmon resonance（SPR）and fluorescence analysis have significant advantages and disadvantages brought by their own detection principle.Surface plasmon resonance has the advantafes of real-time detection,label-free analysis,highly sensitive quantitative detection and so on.But its specificity is heavily dependent on the properties of the biological reagent.Fluorescence analysis has the excellent fearures of strong specificity,less sample consumption and easy to operate.However,the fluorescence detection process is usually interfered by background fluorescence and fluorescence quenching,which makes it difficult to achieve quantitative analysis.Therefore,how to give full play to the advantages of these two detection methods and improve the overall performance of traditional optical biosensors is an urgent problem to be solved in the field of biological detection.In order to solve the above technical problems and realize the complementary advantages of the two detection technologies,a novel portable surface plasmon resonance-fluorescence dual-mode image detection system was innovatively developed in this paper.The system can simultaneously carry out SPR detection and fluorescence analysis,and is also equipped with an automatic injection system.The injection of the entire experimental process can be automatically completed by calling the preparation injection templates.The SPR detection structure of the system only requires a stepper motor to drive the belt.The sliding block on the belt is used to pull the incident light linkages and reflected light linkages on the symmetrical optical module to move symmetrically.The prism position in the middle is fixed.Therefore,it can realize SPR angle scanning mode which keeps incident angle and reflection angle equal all the time.The SPR detection structure studied in this paper has high accuracy and is easy to control.In addition,in order to control the whole detection process of the system,This paper also developed an application software based on the Qt framework to serve the system specially.The software has a simple and user-friendly operation interface,which can realize the functions of whole process monitoring,experimental data saving and reading,sample injection control,data analysis and so on.Finally,the performance of the surface plasmon resonance fluorescence dual-mode image detection system was tested.The results show that the system not only has a practical capability of angle modulation,but also has a high detection sensitivity of 3.72×10^-6RIU for biological reaction.Through the nucleic acid hybridization detection experiment,it can be proved that the system can quickly and efficiently complete the hybridization detection of DNA solution（0.01μM）.The dual-mode image detection experiment of A549lung cancer cells also proved that the system can be used to study the growth inhibitory effect of external drugs on lung cancer cells,and it has great application prospects in drug efficacy evaluation.In addition,the experimental results showed that the two detection signals of A549 lung cancer cells showed a consistent trend under the influence of EGF,indicating that SPR and fluorescence detection technology can support each other in experimental result to exclude false positives or false negatives effect.