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Updated: Jul 18, 2026
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Quantitative Analysis of the Cellular Lipidome of Saccharomyces Cerevisiae Using Liquid Chromatography Coupled with Tandem Mass Spectrometry
Published on: March 8, 2020
Quantitative CARS spectroscopy using the maximum entropy method: the main lipid phase transition
Hilde A Rinia1, Mischa Bonn, Michiel Müller
1Swammerdam Institute for Life Sciences, University of Amsterdam, P.O. Box 94062, 1090 GB Amsterdam, The Netherlands.
Summary
The maximum entropy method precisely analyzes multiplex coherent anti-Stokes Raman scattering (CARS) spectra. This technique quantitatively reveals the lipid phase transition in small, unilamellar DMPC vesicles without prior sample knowledge.
Area of Science:
- Spectroscopy
- Physical Chemistry
- Biophysics
Background:
- Coherent anti-Stokes Raman scattering (CARS) provides vibrational information about molecular systems.
- Phase retrieval is crucial for quantitative analysis of complex spectral data.
- Lipid phase transitions are fundamental to membrane biophysics.
Purpose of the Study:
- To detail and apply the maximum entropy method (MEM) for phase retrieval of multiplex CARS spectra.
- To quantitatively analyze the phase transition of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) vesicles.
- To demonstrate the utility of MEM for time-resolved vibrational spectroscopy.
Main Methods:
- Application of the maximum entropy method (MEM) for phase retrieval.
- Time-resolved multiplex coherent anti-Stokes Raman scattering (CARS) spectroscopy.
- Analysis of the imaginary part of the third-order CARS susceptibility.
Main Results:
- The MEM accurately describes multiplex CARS spectral data, including noise, when using all autocorrelation functions.
- Quantitative analysis of the lipid phase transition in DMPC vesicles was achieved.
- The derived imaginary part of the third-order CARS susceptibility directly relates to the linear vibrational spectrum.
Conclusions:
- The maximum entropy method is a robust tool for phase retrieval in multiplex CARS spectroscopy.
- This approach enables quantitative, model-independent analysis of vibrational spectra.
- The study confirms the acyl-chain order-disorder phase transition in small, unilamellar lipid vesicles.
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