SPR光谱信号的无基线质心法

Without-Baseline Centroid Algorithm for Surface Plasmon Resonance Spectra

为提高角度调制型表面等离子体共振(SPR)传感器的信噪比、分辨率等指标,并减少运算量,在分析固定基线质心法、基于幅值的动态基线质心法的基础上,提出一种确定SPR共振角的无基线质心法。运用SpreetaTM传感器和自行研制的SPR检测仪器,开展多种质量浓度的氯化钠和蔗糖溶液实验,获得SPR光谱数据,并分别采用上述三种质心法进行SPR共振像素计算,得到SPR监控曲线;分析比较三种质心法的运算速度、光源波动敏感度、信噪比和分辨率等指标。结果表明无基线质心法具有运算速度快、不受光源波动影响、信噪比高、分辨率高等特点,能有效提高SPR传感器和检测系统的性能。

To improve performance of the angle-modulated SPR sensor, without-baseline centroid algorithm was proposed based on analysis of the fixed baseline and the dynamic baseline centroid. Experiments of NaC1 and Sucrose（C12O22H11 ）solutions of various concentrations were conducted to obtain SPR spectra on Spreeta？ sensor and self-building SPR instrument, then three different centroid algorithms were used to determine the resonance pixels for sensorgrams, which were used to analyze and compare algorithms from the aspects of computing speed, sensitivity to light fluctuation, signal-to-noise ratio （ SNR）, and resolution. The results show that without-baseline centroid has outstanding performance, high computing speed, low sensitivity to light fluctuation, high SNR and resolution. It thus can effectively improve performance of the SPR sensor and detection system.