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Variable atmosphere pyrolysis of Tosco Oil Shale was performed utilizing a Chemical Data Systems 320 concentrator and a gas blending system. Flame ionization (FID) and nitrogen specific (NPD) detection were performed to determine the atmosphere which maximized hydrocarbon compound formation while minimizing nitrogen compound formation. Comparisons of FID and NPD peak areas as a function of temperature are given for 0%, 10%, 15% and 30% oxygen. The NPD peak areas, as well as the FID peak areas, are contrasted separately. The initial development of a method for distinguishing condensed ring aromatic systems from alkyl substituted aromatic systems was accomplished. N,2,4,6-tetrachloroacetanilide was reacted with standards and with an aromatic fraction of shale oil. Mass spectral analysis and specific element detection (for carbon and chlorine), with a microwave emission detector (MED), were performed on the reaction products. Chlorination of alkyl groups occurred. The formation of olefins was documented, contrary to literature reports. Gas and liquid chromatographic methods for several organoarsenic compounds were developed. The stability of some pentacoordinate organoarsenic compounds was investigated by thermogravimetry. The concentration of arsenic in boiling point distillation cuts of shale oil and in concentrated fractions from liquid chromatographic class separations were obtained by x-ray fluorescence and by inductively coupled plasma with hydride generation. The analysis of shale oil on the GC-MED system was attempted and although a detection limit of 0.4 picograms/second was obtained on the arsenic 228.8 nanometer line no arsenic species could be identified.

Rotational Echo Double Resonance (REDOR) is a powerful solid-state NMR technique that allows the measurement of heteronuclear inter-atomic distances in complex systems such as membrane-bound proteins whose study has been hampered by the limits of X-ray diffraction and solution NMR techniques. We have applied REDOR NMR to explore the structure of the E. coli membrane-bound serine receptor, which is involved in the chemotaxis signaling pathway. 13C-15N and 13C-19F REDOR are used to measure ligand-to-protein distances that map the serine ligand site structure. The results confirm the proposed similarities between the ligand binding sites of the intact membrane-bound serine receptor and the aspartate receptor periplasmic fragment. Preliminary receptor-to-membrane 13C-31P REDOR distance measurements suggest a method for the study of receptor topology. Using REDOR to measure the number of sites that are close to the membrane gives a qualitative insight into the orientation of the protein with respect to the lipid bilayer. We also propose additional multispin REDOR experiments to measure the number of spins that are interacting with the unique ligand spin and thus refine the structure of the ligand site of the receptor. These approaches can be used to map the ligand binding sites and receptor topology in more complex and less understood systems such as human membrane receptors of medical relevance.

A class separation technique for shale oil based on normal phase partition high performance liquid chromatography was developed using a 20 (mu)m cyano bonded substrate. Separation within 30 minutes is achieved between aliphatic (alkane/alkene), aromatic and polar fractions. Reproducible resolution with less than 5% class overlap was achieved. Oil samples from TOSCO II, Paraho, and In Situ retorting processes were compared for aliphatic, aromatic and polar content. After preparative class separation characterization was carried out by fused silica and glass wall coated open tubular capillary gas chromatography and by analytical high pressure liquid chromatography. Compound identification of the aliphatic and aromatic fractions was performed by capillary gas chromatography/mass spectrometry. Mass spectra of the major components were obtained by electron impact at 70 eV. Mass scans were recorded between 50-350 AMU at a scan rate of 128.6 AMU/sec. Mass spectra were compared with those of standards and structural isomers were identified by comparison of their retention times with available standards. A Perkin-Elmer gas phase UV absorbance detector for gas chromatography was evaluated. Parameters such as detection limit, selectivity ratios, dynamic range and compatability with capillary columns were evaluated. Following this characterization the detector was employed for the analysis of shale oil aromatics. Oil shale bitumens, defined as the fraction of shale that is soluble in benzene, were prepared by exhaustive extraction of the raw shale with a 2/1 benzene/methanol mixture. The sample was then separated into paraffinic and aromatic fractions by preparative liquid chromatography on 32-63 (mu)m silica. Each fraction was then analyzed by both packed and high resolution glass capillary gas chromatography with compound identification by GC/MS. The development of coating techniques for high resolution glass capillary columns was also stuided. Both support coated open tubular (SCOT) and wall coated open tubular (WCOT) columns were prepared. The effects of various surface pretreatment techniques such as HCl etching, the use of surfactants, and the effect of different solvents on the overall column efficiency was performed. Both borosilicate (Pyrex) and soda lime glass were employed.

The initial part of this dissertation describes the preparation of the first reported poly(p-xylylene) polymer/polymer composites. Poly(p-xylylene) (PPXN) and its derivatives, known collectively as parylenes, are solvent resistant and blends or composites cannot be easily made by conventional methods. Supercritical carbon dioxide was used as both a plasticizer and solvent to infuse and polymerize a variety of vinyl monomers inside the parylene films. Infrared spectroscopy, wide angle X-ray diffraction, and thermal gravimetric analysis were used to characterize the composites. Multilayer coatings of PPXN and other polymer films were prepared and selectively modified with metal nanoparticles. The second part details the modification of atomic force microscope (AFM) probes using a variety of monochlorosilanes to improve the chemical sensitivity of AFM. X-ray photoelectron spectroscopy revealed that the silane reaction was successful. Adhesion force measurements between the modified probes and similarly modified silicon wafers were performed, but showed only a slight variance between the different tip chemistries. Surfaces with patterned chemistry were prepared and examined with the modified probes using tapping mode AFM. The contrast in the phase images was dependent on the tip chemistry. The ability to confine and direct the motion of liquid droplets on a surface using only gravity and differences in surface chemistry is discussed in the first chapter of Part III. A hydrophobic alkylsilane surface with low contact angle hysteresis was patterned with lines of a more hydrophobic fluoroalkyl silane. Liquid droplets moved easily on the low hysteresis matrix, but pinned at the more hydrophobic lines. A variety of patterns were used to demonstrate that a decrease in the hysteresis reduces the force needed to induce drop motion and also lowers the barriers that are needed to confine the droplets. Condensation on a variety of ultrahydrophobic surfaces was examined in the second chapter of Part III. Optical microscopy showed that water condensed between the hydrophobic surface features before being expelled to the top. The condensed liquid pinned the contact line of a macroscopic droplet and dynamic contact angle measurements revealed an increase in hysteresis which corresponded to a decrease in liquid mobility.

The combination of metal catalyzed oxidation (MCO) reactions and mass spectrometry (MS) is a relatively new method of determining the coordination structure of metalloproteins. The sensitivity of the MCO/MS method gives it significant potential for the study of protein structure. The method takes advantage of Fenton-type oxidation reactions occurring at protein-bound transition-metal ions. These reactions produce reactive oxygen species that modify metal binding residues, and the modified residues are identified using the peptide sequencing ability of MS. This dissertation focuses on increasing the reliability and versatility of the MCO/MS method as a tool for studying metal-protein interactions. The importance of ascorbate concentration in controlling the oxidation yield and specificity of the MCO reactions has been established, and sodium persulfate has been identified as a specific and potent oxidant. Greater insight into the role of ascorbate has allowed us to develop a new "detuned" version of MCO/MS method that can oxidize residues beyond the metal-binding site, making the method more sensitive to minor changes in protein structure that might occur upon metal binding to a protein. Application of the detuned method to Cu binding of β-2-microglobulin suggests some possible structural changes caused by metal binding that might provide insight into the amyloid formation of this protein. The versatility of the MCO/MS approach has been expanded by, improving the speed of the method and extending its application to other metals. In an effort to better study dynamic systems, microwave irradiation has been used to decrease the time required for MCO reactions by a factor of 10. The utility of the MCO/MS method for the study of non-Cu transition metal systems has been illustrated by determining suitable MCO reaction conditions for peptides that bind Mn, Fe, Co and Ni and a whole protein, Nickel superoxide dismutase. Finally, we have studied the effect of amino acid oxidation on the dissociation patterns of peptide ions during tandem MS (MS/MS) experiments and the identification of binding residues. We have found that histidine oxidation changes the peptides dissociation pattern. We demonstrate that an N-terminal derivatization method can be used to simplify the MS/MS interpretation in such circumstances.

Crucial parameters affecting protein-polyelectrolyte complexation include protein charge anisotropy, chain flexibility and polyelectrolyte (PE) charge sequence distribution. PE chain flexibility was found to affect the colloid-binding affinity: stiffer PE's binding more strongly than flexible PEs. However, the definition of chain stiffness should not be conflated with polyelectrolyte persistence length especially in the cases corresponding to the resistance of the chain to bending. A Monte Carlo study of the PE binding site coupled with protein electrostatic potential modeling has further clarified these issues by identifying the nonspecific polyelectrolyte binding site on serum albumin at conditions corresponding to experiments. Examination of the binding between serum albumin and decamers of acrylamidopropanesulfonate and acrylamide of different sequences has shown that the bound decamer retains much of its configurational entropy. Polyelectrolyte stiffness and charge sequences have profound effects on the formation of polyelectrolyte-protein coacervates, as shown by comparison of coacervates made with chitosan vs. those made with a more flexible and fully charged synthetic PE of the same structural charge density. The coacervates with chitosan differ markedly in rheology and dynamic light scattering, and SANS. These differences are explained in the context of a model in which coacervates contain protein-rich dense domains with sizes > than a few hundred nanometers. This model has been supported by fluorescence recovery after photobleaching, CryoTEM and pulsed field gradient NMR. In the context of this model, chain flexibility and the charges of ca, 50 nm polyelectrolyte-protein aggregates have been shown to affect the connectivity and size of the dense domains, which behave as transient obstacles to protein diffusion within the coacervates.

The primary route most cells utilize to acquire iron is the human serum transferrin (hTf)-human transferrin receptor (TfR) mediated uptake pathway. This pathway has been exploited in the treatment of tumor cells; therefore it is vital to understand the interactions between hTf and TfR at the cell surface (pH 7.4) and in the endosome (pH 5.6). The present study investigates the role of iron in hTf binding to TfR to determine whether iron free (apo) hTf can bind TfR at pH 8.3 and understand the conformational changes (associated with iron release) in hTf-TfR at pH 5.6. Electrospray ionization mass spectrometry (ESI-MS) was used to detect the binding products of competitive, single and displacement assays between different forms of hTf (apo, monoferric, diferric) or lobe fragments and TfR at pH 8.3 and 5.6. All of the hTf-bound TfR in a specific but reversible manner at basic and acidic pH. At pH 8.3, diferric (holo)-hTf was the preferred ligand for TfR followed by monoferric-hTf and then apo-hTf. The iron-free lobe of monoferric-hTf was stabilized by the iron-bound lobe (interlobe communication) whereas the apo-hTf was stabilized by the glycan moieties on the C-terminal lobe (C-lobe). Binding assays performed with the lobe fragments suggest the C-lobe of hTf initially binds TfR, which induces allosteric conformational changes resulting in the binding of the N-lobe. However, the latter is incapable of binding TfR on its own. At pH 5.6, apo-hTf and FeNTf (iron in the N-lobe) were the preferred TfR ligands followed by Fe2Tf and FeCTf (iron in the C-lobe). Therefore, iron status of the C-lobe dictated the binding stability to TfR at pH 5.6. When the C-lobe contains iron it cannot completely open, as required for stable TfR binding at pH 5.6; iron occupancy of the N-lobe had no affect on the interaction due to the lack of binding to TfR when the C-lobe has an open conformation.