Summary: Minimum Energy Path to Membrane Pore Formation and Rupture
Christina L. Ting,1
and Zhen-Gang Wang3,*
Biochemistry and Molecular Biophysics, California Institute of Technology, Pasadena, California 91125, USA
Mechanical Engineering, California Institute of Technology, Pasadena, California 91125, USA
Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
(Received 12 January 2011; published 18 April 2011)
We combine dynamic self-consistent field theory with the string method to calculate the minimum
energy path to membrane pore formation and rupture. In the regime where nucleation can occur on
experimentally relevant time scales, the structure of the critical nucleus is between a solvophilic stalk and
a locally thinned membrane. Classical nucleation theory fails to capture these molecular details and
significantly overestimates the free energy barrier. Our results suggest that thermally nucleated rupture
may be an important factor for the low rupture strains observed in lipid membranes.
DOI: 10.1103/PhysRevLett.106.168101 PACS numbers: 87.16.dj, 82.60.Nh, 87.16.dt
Membrane bilayers define boundaries for cells and
are directly involved in many cellular functions .