8. Lipid analysis
The infrared spectrum of lipids contains a wealth of information on lipid composition (head group and chain length/unsaturation) as well as on membrane physical state (chain ordering, phase transition). Furthermore, linear dichroism measures the orientation of different molecule parts with respect to the membrane supporting internal reflection element. Some of these features can be observed in complex systems such as cells.
References
Derenne, A.; Claessens, T.; Conus, C.; Goormaghtigh, E. Infrared Spectroscopy of Membrane Lipids. Encycl. Biophys. 2013, 1074–1081.
Derenne, A.; Vandersleyen, O.; Goormaghtigh, E. Lipid quantification method using FTIR spectroscopy applied on cancer cell extracts. Biochim. Biophys. Acta 2014, 1841, 1200–9.
Goormaghtigh, E.; Ruysschaert, J. Polarized attenuated total reflection spectroscopy as a tool to investigate the conformation and orientation of membrane components. In In “Molecular description of biological membranes components by computer aided conformational analysis”; Brasseur, R., Ed.; CRC Press Inc., Boca Raton, Florida, 1990.