药物筛选和蛋白质组学研究需要高灵敏度和高通量的生物分子相互作用分析仪。该文提出了表面等离子体共振(surface plasmon resonance,SPR)双分差动干涉成像方法和折射率相关因子(refractive index related factor,RIRF)的概念,研制了一种新的分析仪。从传感表面反射的光经过1/2波片、成像透镜和偏振分束镜后分成正交的2束,分别承载同一时刻传感表面的光强互补的2幅干涉图像,投射在2台CCD上,连续同时采集图像并处理后得到反映传感面上折射率变化的RIRF分布图,可解析出生物分子相互作用的特征信息。性能测试结果表明:分析仪动态范围约为0.015折射率单位(refractive index unit,RIU),灵敏度为57.15RIRF/RIU,检测分辨率约为8.5×10-6RIU,检测通量高于100,测量重复性优于95%。该分析仪的阵列生物分子相互作用检测结果和Biacore仪器的检测结果有平行性。
High throughput and high sensitivity biomolecular interaction analysis instruments are urgently needed by drug screening and proteomics research. An instrument was designed and implemented based on a novel surface plasmon resonance (SPR) double differential interferometric imaging raethod and the concept of refractive index related factor (RIRF). After sequentially passing tbruugh a half wave plate, a lens and a polarization beamsplitter, thelight reflected from SPR sensing surface splits up into two orthogonal beams and forms two complementary interferograms of the sensing surface at the same time, which are received by two CCD cameras simuhaneously. The RIRF distribution of the sensing surface was calculated based on these collected images with the information of biomolecular interaction obtained. Experimental results indicated that the dynamic range of this instrument is 0. 015 RIU (refractive index unit) with the sensitivity of 57. 15 RIRF/RIU, the resolution of 8.5 × 10 ^-6 RIU and the throughput of more than 100. The repeatability is better than95%. The experimental results of the instrument are parallel with those of a Biacore instrument.