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Published on: September 26, 2019
Raman microspectroscopy and multivariate data analysis: optical differentiation of aqueous d- and l-tryptophan
1Lehrstuhl für Technische Thermodynamik (LTT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Am Weichselgarten 8, 91058 Erlangen, Germany. stefan.will@fau.de.
Abstract:
The combination of Raman spectroscopy as a sensitive and selective optical measurement technique and multivariate data analysis forms a powerful tool for probing intermolecular interactions between enantiomers. In this study we demonstrate that the optical differentiation of aqueous d- and l-tryptophan solutions is possible using Raman spectroscopy and principal component analysis (PCA). The loadings of the PCA allow identifying these functional groups most relevant for enantiospecific interactions. Through a partial least squares regression (PLSR) a calibration line can be established for the mixing ratio of ternary aqueous d- and l-tryptophan solutions.
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