Degree Type

Dissertation

Date of Award

1994

Degree Name

Doctor of Philosophy

Department

Chemistry

First Advisor

Therese M. Cotton

Abstract

A general review on preparation and methods of characterization of monolayers was given in Chapter 1. Different projects were undertaken in the research of this dissertation. Neutron and X-ray reflection studies of fullerene C[subscript]60 and its derivative monolayers were performed in Chapter 1. Neutron and X-ray reflection measurements and surface pressure isotherms of spread films of C[subscript]60-dodecylamine adduct C[subscript]60-(NH[subscript]2(CH[subscript]2)[subscript]11CH[subscript]3][subscript]x and C[subscript]60-propylamine adduct C[subscript]60-(NH[subscript]2C[subscript]3H[subscript]7][subscript]x indicate that these C[subscript]60 derivatives may form monomolecular layers on water surface. By contrast, neutron reflection and surface pressure vs. area data of spread films of pure C[subscript]60 on aqueous surfaces indicated the formation of inhomogeneous multilayer films with a thickness and a surface roughness exceeding the molecular size. These underivatized fullerenes thus did not form monomolecular films;In Chapter 2, nanoscale size particles were synthesized inside the channel protein MIP-26 using monolayer technique. Cadmium and zinc sulfides were formed within the cavity of a channel protein by a simple process in which a close-packed monolayer of the channel protein was formed on a neutral subphase, transported to a cadmium-chloride-containing subphase, transferred to a quartz slide by Langmuir-Blodgett transfer and exposed to hydrogen sulfide. The cadmium and zinc sulfides were produced in the "quantum dot" size 2 range as evidenced by their markedly blue-shifted optical spectra;In Chapter 4, monolayer characteristics were determined for three isomeric phospholipids and their daughter compounds. These surfactants displayed surprisingly high solubility in the water subphase; stable monolayers could not be formed even at 7-8°C. Reproducible surface pressure-area isotherms were obtained for these surfactants using a subphase of an aqueous 30% polyethylene glycol. Surface potential measurements generally remained constant throughout the range of compression;Finally in this dissertation, the monolayer properties of Bacteriochlorophyll a (BChl a) were investigated at the nitrogen-water interface. This study focused on BChl a monolayers with and without phospholipids as matrix molecules. The interaction between BChl a and these phospholipids was investigated by both surface pressure-area and surface potential measurements. The presence of partially oxidized BChl a was also shown by the Surface Enhanced Resonance Raman Scattering (SERRS) spectra.

DOI

https://doi.org/10.31274/rtd-180813-11539

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Jingyuan Wang

Language

en

Proquest ID

AAI9518452

File Format

application/pdf

File Size

156 pages

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