Langmuir-Blodgett Films as Models for TOF-SIMS Investigation of Biological Systems

Open Access
Zheng, Leiliang
Graduate Program:
Doctor of Philosophy
Document Type:
Date of Defense:
May 29, 2008
Committee Members:
  • Nicholas Winograd, Committee Chair
  • Barbara Jane Garrison, Committee Member
  • Christine Dolan Keating, Committee Member
  • Ahmed A Heikal, Committee Member
  • Langmuir-Blodgett
  • Model
The work presented in this thesis is aimed at utilizing Langmuir-Blodgett (LB) films as model biological systems to improve fundamental understandings and expand applications of time-of-flight secondary ion mass spectrometry (TOF-SIMS) bioanalysis. Chemical imaging of ternary lipid LB monolayer systems shows that it is possible to study lipid-lipid interactions by TOF-SIMS. The incorporation of membrane proteins into the lipid LB monolayer leads to a more representative model and TOF-SIMS imaging is able to identify the membrane protein in the model membrane. Chemically alternating LB multilayer films are developed as a model for fundamental investigations of molecular depth profiling. Organic-organic interface widths are quantitatively studies as a function of temperature, surface topography, and primary ion energy and incident angle. Three-dimensional imaging of the alternating multilayer films visibly displays the “crater effect” and the effect of data acquisition range on interface width measurement is quantitatively studied.