Alignment of Bicelles Studied with High-Field Magnetic Birefringence and Small-Angle Neutron Scattering Measurements

详细信息    查看全文

• 作者：Marianne Liebi ; Peter G. van Rhee ; Peter C. M. Christianen ; Joachim Kohlbrecher ; Peter Fischer ; Peter Walde ; Erich J. Windhab
• 刊名：Langmuir
• 出版年：2013
• 出版时间：March 12, 2013
• 年：2013
• 卷：29
• 期：10
• 页码：3467-3473
• 全文大小：332K
• 年卷期：v.29,no.10(March 12, 2013)
• ISSN：1520-5827

文摘

Birefringence measurements at high magnetic field strength of up to 33 T were used to detect magnetically induced alignment of bicelles composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), cholesterol, and 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine-diethylenetriaminepentaacetate (DMPE-DTPA) with complexed lanthanide ions. These birefringence measurements together with a small-angle neutron scattering (SANS) analysis in a magnetic field showed parallel alignment of the bicelles if the lanthanide was thulium (Tm³⁺), and perpendicular alignment with dysprosium (Dy³⁺). With the birefringence measurements, the order parameter S can be determined as a function of the magnetic field strength, if the magnetic alignment reaches saturation. Additional structural information can be obtained if the maximum induced birefringence is considered. The degree of alignment of the studied bicelles increased with decreasing temperature from 40 to 5 掳C and showed a new bicellar structure comprising a transient hole formation at intermediate temperatures (20 掳C) during heating from 5 to 40 掳C.