Liquid chromatography and Raman spectroscopy (LC-Raman system)
were combined and developed with the aid of the vertical flow method
that enhances the Raman signal intensity. The LC-Raman system enabled
the online acquisition of the nonresonance Raman spectrum of LC eluates.
We employed singular value decomposition (SVD) and subsequent reconstruction
of the components for the analysis of two-dimensional (temporal and
spectral) data. The obtained components were consistent with the Raman
spectra and elution patterns of the samples, indicating the appropriateness
of the SVD-based procedure. The rise and fall times of the elution
band of the temporal component were considered as the instrumental
function. D2O mixed with H2O exhibited increased
full width at half maximum of the elution band of up to 30% in comparison
to the calculated value because of diffusion. Band broadening was
less significant in the case in which an immiscible solute (pentane)
was mixed with H2O. The limits of detection and quantitation
were 1.2 ± 0.1, 2.1 ± 0.1, and 2.7 ± 0.1 mM and 4.1
± 0.1, 6.9 ± 0.1, and 9.1 ± 0.2 mM for the ortho-,
meta-, and para-isomers of methoxyphenol, respectively. The nonresonance
Raman experiment provides the molecular specificity to LC on the basis
of the inherent properties of eluates.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.