Effects of substrate on ultrathin films of poly(γ ‐benzyl‐L‐glutamate) by scanning probe microscopy

Autor: Erwin P. Enriquez, Edward T. Samulski, I. H. Musselman, D. L. Smith, V. F. Guarisco
Rok vydání: 1994
Předmět:
Zdroj: Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films. 12:2523-2529
ISSN: 1520-8559
0734-2101
DOI: 10.1116/1.579051
Popis: Monolayer and bilayer Langmuir–Blodgett films of poly(γ‐benzyl‐L‐glutamate) (PBLG) were prepared on highly oriented pyrolytic graphite (HOPG), mica, silicon, and glass. The films were imaged by atomic force microscopy (AFM) in the contact and tapping modes to develop imaging strategies for ultrathin polypeptide films and to assess the effect of substrate on film microstructure. A better understanding of the local polypeptide film structure could guide future methods of device fabrication. The AFM tapping mode enables long‐term nondestructive imaging of PBLG mono‐ and bilayers for dimensions as small as 0.2 μm. In contrast, contact mode AFM readily damages PBLG films. PBLG has the best monolayer coverage on HOPG, although film is sometimes observed on each of the other three substrates. On HOPG, the monolayer has a predominantly ‘‘lacey’’ structure whereas for the hydrophilic substrates, mica, silicon, and glass, it is ‘‘banded’’ or ‘‘solid.’’ HOPG rarely exhibits a continuous bilayer film whereas the othe...
Databáze: OpenAIRE