@article{smith_mcgillivray_genzer_losche_kilpatrick_2010, title={Neutron reflectometry of supported hybrid bilayers with inserted peptide}, volume={6}, ISSN={["1744-683X"]}, DOI={10.1039/b915800f}, abstractNote={The insertion of a synthetic amphiphilic, α-helical peptide into a supported hybrid bilayer membrane (HBM) was studied by neutron reflectometry to elucidate the resulting nanostructure. The HBM consisted of a self-assembled monolayer of perdeuterated octadecanethiol on gold and an overlying leaflet of acyl-deuterated phosphatidylcholine (d-DMPC). Using contrast variation, several reflectivity spectra were recorded for each step of film fabrication, and simultaneously modeled. This analysis indicated that peptide insertion into the DMPC lipid leaflet is the likeliest mode of incorporation.}, number={5}, journal={SOFT MATTER}, author={Smith, Matthew B. and McGillivray, Duncan J. and Genzer, Jan and Losche, Mathias and Kilpatrick, Peter K.}, year={2010}, pages={862–865} }
 @article{turgman-cohen_smith_fischer_kilpatrick_genzer_2009, title={Asphaltene Adsorption onto Self-Assembled Monolayers of Mixed Aromatic and Aliphatic Trichlorosilanes}, volume={25}, ISSN={["0743-7463"]}, DOI={10.1021/la9000895}, abstractNote={The adsorption of asphaltenes onto flat solid surfaces modified with mixed self-assembled monolayers (SAMs) of aliphatic and aromatic trichlorosilanes with varying wettabilities, aromaticities, and thicknesses is tested. The mixed SAMs are characterized by means of contact angle to assess hydrophobicity and molecular and chemical uniformity, spectroscopic ellipsometry to measure the thickness of the films, and near edge X-ray absorption fine structure (NEXAFS) spectroscopy to assess chemical and molecular composition. The molecular characteristics of the adsorbed asphaltene layer and the extent of asphaltene adsorption are determined using NEXAFS and spectroscopic ellipsometry, respectively. The SAMs are formed by depositing phenyl-, phenethyl-, butyl-, and octadecyl- trichlorosilanes from toluene solutions onto silica-coated substrates; the chemical composition and the wettability of the SAM surface is tuned systematically by varying the trichlorosilane composition in the deposition solutions. The adsorption of asphaltenes on the substrates does not correlate strongly with the SAM chemical composition. Instead, the extent of asphaltene adsorption decreases with increasing SAM thickness. This observation suggests that the leading interaction governing the adsorption of asphaltenes is their interaction with the polar silica substrate and that the chemical composition of the SAM is of secondary importance.}, number={11}, journal={LANGMUIR}, author={Turgman-Cohen, Salomon and Smith, Matthew B. and Fischer, Daniel A. and Kilpatrick, Peter K. and Genzer, Jan}, year={2009}, month={Jun}, pages={6260–6269} }
 @article{smith_efimenko_fischer_lappi_kilpatrick_genzer_2007, title={Study of the packing density and molecular orientation of bimolecular self-assembled monolayers of aromatic and aliphatic organosilanes on silica}, volume={23}, ISSN={["0743-7463"]}, DOI={10.1021/la062475v}, abstractNote={Bimolecular self-assembled monolayers (SAMs) of aromatic and aliphatic chlorosilanes were self-assembled onto silica, and their characteristics were established by contact angle measurement, near-edge X-ray absorption fine structure spectroscopy, and Fourier transform infrared spectroscopy. Three aromatic constituents (phenyltrichlorosilane, benzyltrichlorosilane, and phenethyltrichlorosilane) were studied in combination with four aliphatic coadsorbates (butyltrichlorosilane, butyldimethylchlorosilane, octadecyltrichlorosilane, and octadecyldimethylchlorosilane). Our results demonstrate that whereas SAMs made of trichlorinated organosilanes are densely packed, SAMs prepared from monochlorinated species are less dense and poorly ordered. In mixed systems, trichlorinated aromatics and trichlorinated aliphatics formed SAMs with highly tunable compositions; their surfaces were compositionally homogeneous with no large-scale domain separation. The homogeneous nature of the resulting SAM was a consequence of the formation of in-plane siloxane linkages among neighboring molecules. In contrast, when mixing monochlorinated aliphatics with trichlorinated aromatics, molecular segregation occurred. Although the two shortest aromatic species did not display significant changes in orientation upon mixing with aliphatics, the aromatic species with the longest polymethylene spacer, phenethyltrichlorosilane, displayed markedly different orientation behavior in mixtures of short- and long-chain aliphatics.}, number={2}, journal={LANGMUIR}, author={Smith, Matthew B. and Efimenko, Kirill and Fischer, Daniel A. and Lappi, Simon E. and Kilpatrick, Peter K. and Genzer, Jan}, year={2007}, month={Jan}, pages={673–683} }
 @article{smith_tong_genzer_fischer_kilpatrick_2006, title={Effects of synthetic amphiphilic alpha-helical peptides on the electrochemical and structural properties of supported hybrid bilayers on gold}, volume={22}, ISSN={["0743-7463"]}, DOI={10.1021/la051104w}, abstractNote={Amphiphilic alpha-helices were formed from designed synthetic peptides comprising alanine, phenylalanine, and lysine residues. The insertion of the alpha-helical peptides into hybrid bilayers assembled on gold was studied by a variety of methods to assess the resulting structural characteristics, such as electrical resistance and molecular orientation. Self-assembled monolayers (SAMs) of dodecanethiol (DDT); octadecanethiol (ODT); and 1,2-dipalmitoyl-sn-glycero-3-phosphothioethanol (DPPTE) were formed on gold substrates with and without incorporated peptide. Supported hybrid bilayers and multilayers of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) were formed on SAMs by the "paint-freeze" method of bilayer formation. Modeling of electrochemical impedance spectroscopy data using equivalent electrochemical circuits revealed that the addition of peptide decreased dramatically the resistive element of the bilayer films while maintaining the value of the capacitive element, indicating successful incorporation of peptide into a well-formed bilayer. Near-edge X-ray absorption fine structure spectroscopy data provided evidence that the molecules in the SAMs and hybrid multilayers were ordered even in the presence of peptide. The peptide insertion into the SAM was confirmed by observing the pi* resonance peak correlating with phenylalanine and a peak in the nitrogen K-edge regime attributable to the peptide bond.}, number={4}, journal={LANGMUIR}, author={Smith, MB and Tong, JH and Genzer, J and Fischer, D and Kilpatrick, PK}, year={2006}, month={Feb}, pages={1919–1927} }