Discovery - University of Dundee - Online Publications

Library & Learning Centre

Optimal algorithm for fluorescence suppression of modulated Raman spectroscopy

Optimal algorithm for fluorescence suppression of modulated Raman spectroscopy

Research output: Contribution to journalArticle

View graph of relations

Authors

Research units

    Info

    Original languageEnglish
    Pages11382-11395
    Number of pages14
    JournalOptics Express
    Journal publication date24 May 2010
    Journal number11
    Volume18
    DOIs
    StatePublished

    Abstract

    Raman spectroscopy permits probing of the molecular and chemical properties of the analyzed sample. However, its applicability has been seriously limited to specific applications by the presence of a strong fluorescence background. In our recent paper [Anal. Chem. 82, 738 (2010)], we reported a new modulation method for separating Raman scattering from fluorescence. By continuously changing the excitation wavelength, we demonstrated that it is possible to continuously shift the Raman peaks while the fluorescence background remains essentially constant. In this way, our method allows separation of the modulated Raman peaks from the static fluorescence background with important advantages when compared to previous work using only two [Appl. Spectrosc. 46, 707 (1992)] or a few shifted excitation wavelengths [Opt. Express 16, 10975 (2008)]. The purpose of the present work is to demonstrate a significant improvement of the efficacy of the modulated method by using different processing algorithms. The merits of each algorithm (Standard Deviation analysis, Fourier Filtering, Least-Squares fitting and Principal Component Analysis) are discussed and the dependence of the modulated Raman signal on several parameters, such as the amplitude and the modulation rate of the Raman excitation wavelength, is analyzed. The results of both simulation and experimental data demonstrate that Principal Component Analysis is the best processing algorithm. It improves the signal-to-noise ratio in the treated Raman spectra, reducing required acquisition times. Additionally, this approach does not require any synchronization procedure, reduces user intervention and renders it suitable for real-time applications. (C) 2010 Optical Society of America

    Documents

    Library & Learning Centre

    Contact | Accessibility | Policy