Ordered Langmuir-Blodgett Films of Amphiphilic #beta#-Hairpin Peptides Imaged by Atomic Force Microscopy

摘要

Langmuir and Langmuir-Blodgett (LB) films of peptides have a number of potential applications. The fulfillment of this potential will depend on developing the molecular level undertanding needed to control both the order withing these films and their structures. Self-assembly in thin peptide films can be characterized by circulr dichroism and IR spectroscopies, fluorescence microscopy, and at high resoltion by grazing incidence X-ray diffraction (GIXD), and atomic force microscopy (AFM). Previous fluorescence microscopy results demonstrate that peptide 1 selfassembles into liquid- and solid-phase domains at the air-water (A-W) interface. Here, we have used AFM with carbon nanotube tips to image LB films of 1 and its longer relative, 2. The images show crystalline, two-dimensional order in films of 1 and 2 and demonstrate that the assembly parameters can be varied through well-defined changes in peptide structure.