Characterization of Peptide-Guided Polymer Assembly at the Air/Water Interface
详细信息 查看全文
- 作者：Annabel H. Muenter ; Jens Hentschel ; Hans G. Bö ; rner ; Gerald Brezesinski
- 刊名：Langmuir
- 出版年：2008
- 出版时间：April 1, 2008
- 年：2008
- 卷：24
- 期：7
- 页码：3306 - 3316
- 全文大小：765K
- 年卷期：v.24,no.7(April 1, 2008)
- ISSN：1520-5827
文摘
An organo-soluble, peptide-polymer conjugate that combines poly(n-butyl acrylate) with a 
ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheet-forming peptideis spread at the water surface to investigate peptide-guided self-assembly in a two-dimensional environment. Singlelayers of the conjugate are studied to gain information on the packing, orientation, and structure of the conjugatemolecules using standard monolayer techniques: isotherms, grazing incidence X-ray diffraction (GIXD), and infraredreflection absorption spectroscopy (IRRAS). At all conditions studied, the stabilizing ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheet network consists ofantiparallel ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheets oriented parallel to the air/water interface. The incorporation of temporary switch defects in thepeptide segment enables ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheet assembly to be triggered at different packing densities. Stable monolayers, with lowcompressibilities similar to peptide monolayers, form when ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheet assembly occurs in monolayers that contain closelypacked conjugate molecules. Langmuir-Schaefer transfer of the switched monolayer seeded with 1/1000 part stearicacid results in a transferred monolayer containing ordered domains with 7 nm wide stripes, a width in agreement withthe end-to-end distance of the conjugate molecule. In this interfacial system, high packing densities and a hydrophobicseed molecule play an important role in ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheet network and structure formation. Both effects likely direct the highlyordered ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheet structure because of ges/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-strand prealignment. Insights gained from self-assembly in this system can beapplied to peptide aggregation mechanisms in more complex interfacial environments.