Fourier Transform Infrared Spectroscopy in the Study of Lipid Phase Transitions in Model and Biological Membranes: Practical Considerations

Fourier transform infrared (FT
IR
) spectroscopy is a powerful, nonperturbing technique that has been used to good effect for the detection and characterization of lipid phase transitions in model and natural membranes. The technique is also quite versatile, covering a wide range of sophisticated applications, from which fairly detailed information about the structure and organization of membranes and other lipid assemblies can be obtained. In this chapter, an introduction to this particular application of FTIR spectroscopy is presented. Special emphasis is put on how the technique can be used to study lipid phase transitions under biologically relevant conditions. The chapter is intended to give an overview of the capabilities of FTIR spectroscopy in the field of lipid and biomembrane research, and provide the reader with some practical guidelines for the design and execution of simple FTIR spectroscopic experiments suitable for the detection and characterization of lipid phase transitions in hydrated lipid bilayers.