Namba A, Musha T
Olympus Optical Co. Ltd, Tokyo, Japan.
Front Med Biol Eng. 1991;3(2):113-22.
A new optical method is presented here for detecting immunoreaction by means of the forward and depolarized light scattering by coated carrier particles. By this approach, a short-time measurement of antigen-antibody reactions was concisely achieved. The method covered in this article is based on using double-scattered light. While light that is single-scattered by microspheres is polarized parallel to the incident light polarization, double-scattered light contains depolarized components. The normalized fractional variance in the single-scattered field is inversely proportional to the particle concentration, whereas that in the double-scattered field is inversely proportional to the square of the particle concentration. Due to this difference, the decrease of the particle concentration during the agglutination reaction is more sensitively detected through the measurement of the fractional variance in the double-scattered field. In addition, undesirable light scattered from non-aggregated microspheres is reduced by using the method summarized here. This study is based on the assumption that the particle concentration of the double-scattered field is 4.5 x 10(11) particles/cm3. The latex spheres coated with antibody molecules aggregated after adding the antigen and, as a result, the fractional variance rapidly increased before leveling off after 5-10 min. The antigens measured were alpha-fetoprotein (AFP) and immunoglobulin E (IgE).
本文提出了一种新的光学方法，用于通过包被载体颗粒的前向光散射和去偏振光散射来检测免疫反应。通过这种方法，可简洁地实现抗原-抗体反应的短时间测量。本文所涵盖的方法基于双散射光的利用。当微球单次散射的光与入射光偏振平行偏振时，双散射光包含去偏振成分。单次散射场中的归一化分数方差与颗粒浓度成反比，而双散射场中的归一化分数方差与颗粒浓度的平方成反比。由于这种差异，通过测量双散射场中的分数方差，可以更灵敏地检测凝集反应过程中颗粒浓度的降低。此外，使用本文总结的方法可减少非聚集微球散射的有害光。本研究基于双散射场中颗粒浓度为4.5×10¹¹个颗粒/cm³的假设。添加抗原后，包被抗体分子的乳胶球发生聚集，结果，分数方差在5 - 10分钟后趋于平稳之前迅速增加。所检测的抗原为甲胎蛋白（AFP）和免疫球蛋白E（IgE）。
