Research is in the area of biological physics, with an interface with soft condensed matter physics. The particular systems under study are lipid bilayers, which form the structural basis of biomembranes. My studies employ x-ray and neutron scattering, theoretical modeling, statistical mechanical calculations and simulations, and measurements of specific heat and volume as a function of temperature. The first goal is to obtain reliable data for basic structural properties. The second goal is to elucidate the interactions between bilayers. For biologically relevant fluid phase lipid bilayers, both goals involve measuring nanoscale fluctuations, which we do using  synchrotron x-rays. A longer-range goal is to understand how the molecular interactions bring about the structure and the fluctuations.

Selected Publications

See website http://lipid.phys.cmu.edu or http://bilayer.phys.cmu.edu for other publications.

N. Kučerka, J. Pencer, J. N. Sachs, J. F. Nagle, and J. Katsaras, “Curvature effect on the structure of phospholipid bilayers”, Langmuir 23, 1292-99 (2007).

S. Tristram-Nagle and J. F. Nagle, “HIV-1 Fusion Peptide Decreases Bending Energy, Promotes Curved Fusion Intermediates”, Biophysical Journal 93, 2048-2055 (2007).

J. Pan, S. Tristram-Nagle and J. F. Nagle, “Temperature Dependence of Structure, Bending Rigidity and Bilayer Interations of DOPC Bilayers”,  Biophysical Journal 94, 117-124 (2008).

 J. C. Mathai, S. Tristram-Nagle, J. F. Nagle and M. L. Zeidel, “Structural Determinants of Water Permeability through the Lipid Membrane”, J. Gen. Physiol. 131: 59-68 (2008).

 J. F. Nagle, J. C. Mathai, M. L. Zeidel and S. Tristram-Nagle, “Theory of Passive Permeability through Lipid Bilayers”, J. Gen. Physiol. 131: 77-85 (2008).