Research On The High-Throughput Surface Plasmon Resonance Sensing Technique And Its Application

Surface plasmon resonance （SPR） is a label-free and highly-sensitive sensingtechnique. The application of SPR sensing in life science is of great interests. In recentyears, with the development of microarrays, the demands for microarray detectionmethods become higher and higher. However, present SPR techniques are still in needof improvement for providing high-throughput and high-accuracy detection ofmicroarrays.In this article, we study the basic physics of SPR, and analyze the criticalcharacteristics of SPR sensors. To overcome the problems present in the microarraydetection, firstly we proposed a polarization interferometry based high-throughputwavelength-interrogation SPR sensing approach, and further constituted the detectionsystem. We applied a parallel scan mechanism which line-focused the excitation lightand was able to monitor a line region on the array surface in a single scan. Therefore, incomparison with the point scan strategy, the parallel scan mechanism greatly improvedthe detection throughput. Moreover, we managed to apply the polarizationinterferometry modulation method to the wavelength-interrogation SPR system for thefirst time, which contributed to the improvement of detection characteristics. Referringto the detection performance, the spatial resolution is better than85μm. The refractiveindex resolution is3.9107RIU, which is significantly better than a105RIUlevel of most two-dimensional wavelength-interrogation SPR sensors. Thedetection limit is104cfu/mL when detecting bacteria. These characteristicsare adequate and good for microarray detection.In order to confirm the SPR results, we developed a hyperspectral fluorescenceimaging method for analysis of microarrays. The hyperspectral mechanism is able toimprove the accuracy of fluorescence detection by acquisition of whole fluorescentspectra. Based on the improvements we have made both in the SPR and fluorescenceimaging, we further proposed a concurrent detection approach which was able toprovide both SPR and hyperspectral fluorescence imaging results. In this way, we couldcarry out more comprehensive analysis with multiple quantities and explore the essenceof biological and biochemical reactions. For fluorescence imaging, the spatial resolution is19.7μm, and the fluorescence detection sensitivity is0.61fluors/μm². For SPRimaging, the refractive index resolution is7.2×10^-7RIU, and the detection limitis104cfu/mL. The performance of this concurrent system provides high-throughputand highly-sensitive detection of microarrays.Then we carried out basic biological experiments, including the DNAhybridization and protein reactions, using these two newly-proposed high-throughputSPR systems. The experimental results proved the application potential of our systems.Finally, in the prospect of this article, we introduced the exploring work we arepresently taking which focused on a novel long-range surface plasmon resonancesensing technique, including the method design, system constitution and biologicalapplications.