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Full-Text Articles in Physical Sciences and Mathematics
Self-Assembly Of Helical Ribbons, Yevgeniya V. Zastavker, Neer Asherie, Aleksey Lomakin, Jayanti Pande, Joanne M. Donovan, Joel M. Schnur, George B. Benedek
Self-Assembly Of Helical Ribbons, Yevgeniya V. Zastavker, Neer Asherie, Aleksey Lomakin, Jayanti Pande, Joanne M. Donovan, Joel M. Schnur, George B. Benedek
Yevgeniya V. Zastavker
The self-assembly of helical ribbons is examined in a variety of multicomponent enantiomerically pure systems that contain a bile salt or a nonionic detergent, a phosphatidylcholine or a fatty acid, and a steroid analog of cholesterol. In almost all systems, two different pitch types of helical ribbons are observed: high pitch, with a pitch angle of 54 ± 2°, and low pitch, with a pitch angle of 11 ± 2°. Although the majority of these helices are right-handed, a small proportion of left-handed helices is observed. Additionally, a third type of helical ribbon, with a pitch angle in the range …
Tension-Induced Straightening Transition Of Self-Assembled Helical Ribbons, Yevgeniya V. Zastavker, Brice Smith, George B. Benedek
Tension-Induced Straightening Transition Of Self-Assembled Helical Ribbons, Yevgeniya V. Zastavker, Brice Smith, George B. Benedek
Yevgeniya V. Zastavker
Helical ribbons with pitch angles of either 11° or 54° self-assemble in a wide variety of quaternary surfactant-phospholipid/fatty acid-sterol-water systems. By elastically deforming these helices, we examined their response to uniaxial forces. Under sufficient tension, a low pitch helix reversibly separates into a straight domain with a pitch angle of 90° and a helical domain with a pitch angle of 16.5°. Using a newly developed continuum elastic free energy model, we have shown that this phenomenon can be understood as a first order mechanical phase transition.