Wednesday, June 18, 2008 - 3:37 PM
Room 6 (McKimmon Conference Center)
529

Pattern Formations in Langmuir Films Made of Chiral Lipid Molecules

Prem B. Basnet, Kent State University, Kent, OH, Elizabeth K. Mann, Kent State University, Kent, OH, and Sahraoui Chaieb, University of Illinois at Urbana-Champaign, Urbana, IL.

Langmuir films of a strongly chiral lipid, 1,2-bis(10,12 Tricosadiynoyl)-sn-Glycero-3-Phosphoethanolamine, form compact spiral and target patterns when compressed between two movable barriers in a Langmuir trough. These patterns are formed from 30C up to the gel transition at 38C. At lower temperatures, both left and right handed single-armed spirals form, with many defects, while at higher temperatures, the patterns form defect-free concentric circles. Critical pressures for pattern formation increase with increasing temperature. A possible mechanism is competition among elasticity, chirality, and the boundary conditions at the core of the domains.