基于平滑样条曲线结合离散状态转移算法的拉曼光谱基线校正方法  

Baseline Correction for Raman Spectroscopy Using Cubic Spline Smoothing Combined with Discrete State Transformation Algorithm

作　　者：姚泽楷 蔡耀仪[1] 李诗文 陈奕霏 Yao Zekai;Cai Yaoyi;Li Shiwen;Chen Yifei(College of Engineering and Design,Hunan Normal University,Changsha 410081,Hunan,China)

机构地区：[1]湖南师范大学工程与设计学院,湖南长沙410081

出　　处：《中国激光》2022年第18期160-168,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(61903138);湖南省自然科学基金(2020JJ5366);国家级大学生创新项目(S202010542003)。

摘　　要：作为一种无损检测技术,拉曼光谱基于其指纹谱特性和精确捕获分子振动的能力能够获取物质的定性和定量信息,在环境、化工和生物医学等领域得到日益广泛的应用。然而,在拉曼光谱测量过程中,荧光散射信号所造成的光谱基线漂移会导致拉曼光谱特征峰识别困难,对定性或定量分析结果产生不同程度的负面影响。目前,各种基线校正方法已经成功地应用于各种光谱的处理,但这些方法的参数仍须根据研究者的经验来设置。为此提出一种基于平滑样条结合离散状态转移算法(DSTAspline)的基线校正方法,能够基于离散状态变换策略实现全局寻优,得出荧光背景的最佳估计结果,并基于平滑样条曲线拟合得到最优基线曲线。在实验中,选取模拟光谱和实际物质并与现有方法对比其基线校正结果。实验结果表明,所提出的方法能够有效地消除具有不同强度荧光背景的拉曼光谱的基线漂移,且不需要复杂的参数设置和调整过程,为进一步利用拉曼光谱数据实现物质的定性和定量分析提供可靠的信息。Objective Raman spectroscopy is a non-destructive testing technology.Qualitative and quantitative information of substances can be obtained by Raman spectroscopy based on its fingerprint spectrum characteristics and good performance,so it has been widely used in environmental,chemical,biomedical,and other fields.However,in Raman spectrum measurement,the spectral baseline drift caused by fluorescence scattering signal will make it challenging to identify the characteristic peaks of the Raman spectrum,which will have different degrees of adverse effects on the results of qualitative or quantitative analysis.Various baseline correction methods have been successfully applied to multiple spectral processing.However,the parameters of these methods still need to be set according to the experience of the researchers.In this paper,a baseline correction method based on cubic spline smoothing combined with discrete state transformation algorithm(DSTAspline)is proposed,which can find the best estimation result of fluorescence background globally based on discrete state transformation strategy and obtain the optimal baseline curve based on smooth spline curve fitting,thus completing the baseline fitting of Raman spectra signals.In the experiment,the spectra of two kinds of actual substances are selected,and the baseline correction of the Raman spectra is carried out based on the proposed algorithm.The experimental results show that the proposed method can effectively eliminate the baseline drift of Raman spectra with different intensity fluorescence backgrounds,thereby obtaining the real Raman spectra signals without complex parameter setting and adjustment processes.It provides reliable information for further Raman spectra data to realize the qualitative and quantitative analysis of substances.Methods In our proposed method,cubic spline smoothing is used to fit the baseline drift for Raman spectra.A binary vector V with the same dimension as the number of wavenumber points in the Raman spectrum is initially generated by the

关 键 词：光谱学 拉曼光谱 基线漂移 平滑样条曲线 离散状态转移算法 基线校正 

分 类 号：O436[机械工程—光学工程]