在此前曾提出过一种新型二维折射率探测方法——并行扫描光谱表面等离子体共振(surface plasmon resonance, SPR)成像方法。在这种方法中,使用线形光照明,CCD得到的图像包含SPR光谱信息和一维空间信息,进而通过计算可得到折射率的一维分布信息。通过一维扫描,就能够得到整个被扫描区域内的折射率二维分布信息。该方法具有高灵敏、高通量的优点,适合微阵列(microarray)的检测, 并完善了这种方法的数据处理过程,使用空气折射率作为参考,消除了无法精确控制入射角的难题。使用该方法对手工点制的军团菌mip DNA探针微阵列进行了检测,证明了这种方法高灵敏无标记地探测微阵列的可行性。我们得到的军团菌mip DNA探针制备浓度与其等效折射率的关系,这对基于SPR的微阵列技术的发展有着重要的参考意义。
The authors have previously proposed a novel refractive index two-dimensional sensing technique named "parallel scan spectral surface plasmon resonance imaging". In the technique, with a line-shaped light illumination, an image acquired with CCD detector could provide both SPR wavelength information and one-dimensional spatial distribution, and then provide one-dimensional distribution of refractive index with further calculation. Thus, two-dimensional distribution of refractive index of the entire sensing area can be obtained with one-dimensional optical line parallel scan. The technique offers advantages of both high sensitivity and high throughput, and could have potential applications in microarray analysis. In the present paper, the authors improve the data processing methods of the technique. The authors use the refractive index of air as a reference to get over the problem of precision of the incident angle. The authors also sense a manually dotted Legionella pneumophila mip DNA probe array with this technique and prove the feasibility of sensing mieroarrays by this highly sensitive and label-free technique. The rela tion between the equivalent refractive indices and the concentrations of the dotted Legionella pneumophila mip DNA probes is obtained, which has important reference value for further study.