title: Solvent relaxation in phospholipid bilayers: principles and recent applications.
abstract: Although there exist a number of methods, such as NMR, X-ray, e.g., which explore the hydration of phospholipid bilayers, the solvent relaxation (SR) method has the advantage of simple instrumentation, easy data treatment and possibility of measuring fully hydrated samples. The main information gained from SR by the analysis of recorded "time-resolved emission spectra" (TRES) is micro-viscosity and micro-polarity of the dye microenvironment. Based on these parameters, one can draw conclusions about water structure in the bilayer. In this review, we focus on physical background of this method, on all the procedures that are needed in order to obtain relevant parameters, and on the requirements on the fluorescence dyes. Furthermore, a few recent applications (the effect of curvature, binding of antibacterial peptides and phase transition) illustrating the versatility of this method are mentioned. Moreover, limitations and potential problems are discussed.
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-18223, Prague 8, Czech Republic.
authors.forename: Piotr
authors.initials: P
authors.lastname: Jurkiewicz
authors.forename: Jan
authors.initials: J
authors.lastname: Sýkora
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Olzyńska
authors.forename: Jana
authors.initials: J
authors.lastname: Humpolícková
authors.forename: Martin
authors.initials: M
authors.lastname: Hof
mesh_terms: D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D005456:Fluorescent Dyes / Q000032:analysis; D008051:Lipid Bilayers / Q000737:chemistry*; D008560:Membrane Fluidity; D010743:Phospholipids / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D010743:Phospholipids; D012997:Solvents