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This paper presents the results of a continuing investigation of several functionalized SPION MR contrast agents and the solid state NMR studies of plasma polymerized Allyl Alcohol thin films. Several species of functionalized SPIONs were tested; the most successful SPIONs were the melamine dendron, polyimidazole, and conjugated nucleic acid SPIONs. The study of the MR responses of the melamine dendron SPIONs determined that these SPIONs undergo reversible clustering and that their pH sensitive MR responses are due to increased clustering at pH> 4. The MR responses of the polyimidazole functionalized SPIONs (both the dopamine and carboxylate linked) indicate a pH sensitive MR response well within the physiological regime (inflection point pH ~6) as well as excellent baseline relaxivities. However, perhaps due to the low polyimidazole loading onto the SPION core, these agents were very sensitive to ionic environment. CPMAS studies of pulsed plasma polymerized allyl alcohol thin films indicated that the hydrophobic films had a more ordered structure than the hydrophilic films; however, all poly-allyl alcohol thin films had a highly amorphous structure. The use of synthetic mica as a substrate for CPMAS studies of polymer thin films is also discussed.

A high throughput proteomic analysis method is described here that uses more economically favorable, easily manufactured probe surface that can be directly incorporated on the MALDI target. On-Probe Affinity Capture (OPAC) MALDI is a method that uses the RF pulsed plasma modified target surfaces for the protein purification, separation and identification all on the same single probe and one of the highest advantage of this method is the number of different experiments that can be carried out simultaneously using the intelligent design of the probe. The new design of the OPAC probe presented in this dissertation gives the ability to perform about 100 different experiments on one single MALDI target. These OPAC probes can be used for the fractionation and analysis of proteins from complex biologically derived samples. The separated proteins can be identified on the OPAC probe using it directly as the MALDI target and selecting a proper elution solution that depends on the chemistry of the OPAC probe, the surface bound proteins can be eluted and incorporated into the matrix crystal. This dissertation focuses mainly on developing this method for analysis of different samples. A tryptic digest of a single protein was separated and identified by submitting the peak lists to MASCOT database search and the sequence coverage obtained before and after fractionation has been compared. Then a mixture of tryptic peptides of five different known proteins were fractionated on OPAC surfaces and the identification of proteins obtained was compared before and after fractionation. Further developing this technique, biologically derived mixtures of proteins from two different well studied sources have been analyzed using OPAC-MALDI. Escherichia coli bacterial proteome was digested and fractionated and the peptides were studied using De Novo sequencing method and their affinity fractionation behavior is confirmed by calculating the iso electric point (pI) and the hydrophobicity of the predicted peptide sequence. Synechosystis sp PCC 6803 was cultured and the protein extracts were prepared for the OPAC studies. The clear fractionated of this mixture was observed and the amount of information derived after fractionation is found to be significantly higher than the unfractionated sample. Taking a slightly different approach, a phosphoprotein binding OPAC probe was prepared using commercially available poly(methyl methacrylate) (PMMA) film. The hydrolyzed PPMA films were reacted with CuCl2 solution to incorporate metal ions on the surface by electrostatic interaction, which then facilitates the phosphoprotein binding on the OPAC probe. This was demonstrated using a binary mixture of commercially available peptides and fractionating the mixture on Cu-impregnated PMMA film. Finally, in a collaborative work, the possibility of increased surface binding capacity was explored by using a synthetic organic nanosponge surface that expands and collapses due to change of pH. These brush polymers were prepared by Dyer group and a binary mixture of peptides were fractionated and analyzed by MALDI MS.

The thesis describes surface topography of a-CSi:H films deposited by continuous wave plasma enhanced chemical vapor deposition (PECVD) based on tetravinylsilane monomer (TVS). Thin films are completely used in many fields of modern technologies and their physical and mechanical properties are affected by thin film preparation techniques. In this thesis the thin films were deposited by PECVD method on silicon wafers with the pure TVS monomer. Deposited samples were topographically described and analyzed using atomic force microscopy (AFM). The main characteristics which were described are RMS roughness, autocorrelation function and a size distribution of grains on the thin film surface. Analysis was realized with two sets of samples with different powers and thickness. The main results were statistically evaluated like a mixture of object on the surface prepared in different deposition conditions.

Proposed diploma thesis is focused on preparation and characterization of the plasma polymer thin films based on tetravinylsilane monomer (TVS). Plasma enhanced chemical vapour deposition (PECVD) method involving pulse and continual plasma discharge modes were used for thin film deposition on silicon wafer pieces. Reactive plasma composition was containing pure TVS or mixtures of TVS and argon or oxygen gas. Atomic force microscopy was used for surface topography and roughness characterization. Cyclic nanoindentation was involved to measurements to determine the Young’s modulus and hardness of prepared films and scratch test was performed to evaluate the degree of adhesion. Special attention was drawn to the characterization of films with a Young’s modulus below 10 GPa. Tip geometry of indenter influence on scratch test was also commented. Surface and mechanical properties of thin films in relation to the deposition conditions were correlated to the obtained results and final analysis of deposition conditions influence is proposed.