Etxebarria-Elezgarai Jaione, Mowat Miriam, Lopez Eneko, Rodríguez Carlos, Olaetxea Ion, Seifert Andreas
CIC nanoGUNE BRTA, Tolosa Hiribidea 76, Donostia-San Sebastián 20018, Spain.
IKERBASQUE, Basque Foundation for Science, Euskadi Plaza 5, Bilbao 48009, Spain.
Anal Chem. 2020 Dec 15;92(24):16236-16244. doi: 10.1021/acs.analchem.0c04105. Epub 2020 Nov 25.
This work demonstrates a novel strategy to improve the sensing performance of a prism-coupled surface plasmon resonance system by Gaussian beam shaping and multivariate data analysis. The propagation of the beam along the optical system has been studied using the Gaussian beam approximation to design the incident beam such that the beam waist is aligned precisely and that stability is assured at the metal-dielectric interface. This renders a collimated incident beam, hence least angular dispersion, yielding a stronger and sharper plasmonic resonance. Moreover, we use the multivariate analysis method partial least squares that combines multiple features of the surface plasmon resonance curve and allows for a more precise analysis of the plasmonic response. Compared to univariate analysis, partial least squares improves typical sensing performance parameters remarkably. The combination of both aspects, beam shaping and multivariate analysis, overcomes current limitations of plasmonic detection systems. Thereby, we improve analytical sensitivity by a factor of 16, decrease the prediction error of the concentration of an unknown analyte by a factor of 11, and enhance resolution to the order of 5 × 10 RIU in angular interrogation.
这项工作展示了一种通过高斯光束整形和多变量数据分析来提高棱镜耦合表面等离子体共振系统传感性能的新策略。利用高斯光束近似研究了光束在光学系统中的传播，以设计入射光束，使束腰精确对准，并确保在金属-电介质界面处的稳定性。这产生了准直的入射光束，从而具有最小的角色散，产生更强、更尖锐的等离子体共振。此外，我们使用多变量分析方法偏最小二乘法，该方法结合了表面等离子体共振曲线的多个特征，并允许对等离子体响应进行更精确的分析。与单变量分析相比，偏最小二乘法显著提高了典型的传感性能参数。光束整形和多变量分析这两个方面的结合克服了等离子体检测系统当前的局限性。由此，我们将分析灵敏度提高了16倍，将未知分析物浓度的预测误差降低了11倍，并在角度询问中将分辨率提高到5×10 RIU量级。
