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Oligosaccharide identification and mixture quantification using Raman spectroscopy and chemometric analysis.

Melissa F Mrozek·Dongmao Zhang·Dor Ben-Amotz
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Abstract

This work demonstrates the feasibility of using Raman spectroscopy for the analysis of small quantities of chemically similar oligosaccharides and their mixtures. Raman spectra were obtained from 10-microL aliquots of 1 mM solutions of maltotetraose and/or stachyose after deposition onto an electrochemically roughened silver substrate (and the resulting spectral features are attributed to a combination of normal and surface-enhanced Raman scattering). These compounds were selected because they are representative of glycans derived from post-translationally modified proteins which, like these compounds, often consist of isomers of equal mass and similar shape. Replicate spectral measurements were recorded and processed using a partial-least-squares (PLS) classification and quantification algorithms with a leave-one-batch-out (LOBO) training and testing procedure. Spectra derived from solutions of individual sugars were identified with 100% accuracy, and mixtures of the two sugars were quantified with an average error of 2.7% in the relative maltotetraose/stachyose composition for mixtures with a total oligosaccharide concentration of 1 mM.

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AlgorithmsIsomerismMaltoseOligosaccharidesPolysaccharidesProteinsSpectrum Analysis, RamanJournal ArticleResearch Support, Non-U.S. Gov't

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Melissa F Mrozek, Dongmao Zhang, Dor Ben-Amotz. 2004-01-02. Oligosaccharide identification and mixture quantification using Raman spectroscopy and chemometric analysis.. https://doi.org/10.1016/j.carres.2003.09.019

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