Plasmonics and Nanophotonics Laboratory, Department of Laser Technologies, Center for Physical Sciences and Technology, Sauletekio Ave. 3, LT-10257 Vilnius, Lithuania.
Int J Mol Sci. 2023 Jan 19;24(3):2029. doi: 10.3390/ijms24032029.
In this study, we present an analysis of the optical response of strong coupling between SPR and labeled proteins. We demonstrate a sensing methodology that allows to evaluate the protein mass adsorbed to the gold's surface from the Rabi gap, which is a direct consequence of the strong light-matter interaction between surface plasmon polariton and dye exciton of labeled protein. The total internal reflection ellipsometry optical configuration was used for simulation of the optical response for adsorption of HSA-Alexa633 dye-labeled protein to a thin gold layer onto the glass prism. It was shown that Rabi oscillations had parabolic dependence on the number of labeled proteins attached to the sensor surface; however, for photonic-plasmonic systems in real experimental conditions, the range of the Rabi energy is rather narrow, thus it can be linearly approximated. This approach based on the strong coupling effect paves the alternative way for detection and monitoring of the interaction of the proteins on the transducer surface through the change of coupling strengths between plasmonic resonance and the protein-dye complex.
在这项研究中，我们分析了 SPR 和标记蛋白质之间强耦合的光学响应。我们展示了一种传感方法，该方法可以从拉比能隙评估吸附在金表面的蛋白质质量，这是表面等离激元与标记蛋白质的染料激子之间强光物质相互作用的直接结果。全内反射椭圆偏振光学配置用于模拟 HSA-Alexa633 染料标记蛋白质吸附到玻璃棱镜上的薄金层的光学响应。结果表明，拉比振荡与附着在传感器表面上的标记蛋白质的数量呈抛物线关系；然而，对于实际实验条件下的光子等离子体系统，拉比能量的范围相当窄，因此可以进行线性近似。这种基于强耦合效应的方法为通过等离子体共振与蛋白质-染料复合物之间的耦合强度的变化来检测和监测传感器表面上蛋白质的相互作用开辟了替代途径。
