Stephen E Rankin

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Lower chlorinated polychlorinated biphenyls (PCBs) are readily metabolized via hydroxylated metabolites to reactive PCB quinones. Although these PCB metabolites elicit biochemical changes by mechanisms involving cellular target molecules, such as the aryl hydrocarbon receptor, and toxicity by interacting with enzymes like topoisomerases, only few PCB(More)
We describe a simple, inexpensive coating method to produce thin silica and titania films with surfactant templated, orthogonally tilted cylindrical nanopore arrays. These films can be deposited onto any substrate because orientation of the 2D hexagonally close packed (HCP) mesophases out of the plane of the film is directed by a chemically neutral(More)
Poly(propylene glycol) (PPG) of moderately high molecular weight (M(n) = 3500 Da) exhibits amphibious behavior in aqueous solution in that it is hydrophilic at low temperature but hydrophobic at high temperature. This property is utilized to generate porous titania thin films with a hierarchical structure consisting of macroporous voids/cracks in films with(More)
Tethering of monodisperse, chain-end-functionalized polymer from dilute solution to a solid surface shows three regimes of kinetics. This paper presents support for the hypothesis that the experimentally observed third regime is indeed the transition from mushroom to brush and that it occurs in a spatially nonuniform manner. Both time-step snapshots(More)
While organically bridged alkoxysilane precursors such as bis(triethoxysilyl)ethane (BTESE) find increasing use in materials synthesis, their polymerization still has not been subject to detailed kinetic investigations. One factor complicating the measurement and interpretation of the behavior of these monomers is their tendency to aggregate during(More)
The adsorption of tetraethylammonium perfluorooctylsulfonate (TEA-FOS) from aqueous solution onto hydroxylated germanium is studied using in situ polarized attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The adsorption is monitored at a series of bulk solution concentrations spanning from well below to above the critical(More)
A series of hydrocarbon and fluorocarbon carbohydrate surfactants with different headgroups (i.e., gluco-, galacto- and maltopyranoside) and (fluorinated) alkyl tails (i.e., C7 and C14 to C19) was synthesized to investigate trends in their cytotoxicity and haemolytic activity, and how surfactant-lipid interactions of selected surfactants contribute to these(More)
Alkyl β-d-xylopyranosides are highly surface active, biodegradable surfactants that can be prepared from hemicelluloses and are of interest for use as pharmaceuticals, detergents, agrochemicals, and personal care products. To gain further insights into their structure-property and structure-activity relationships, the present study synthesized a series of(More)
We are interested in the development of surfactants derived from hemicellulosic biomass, as they are potential components in pharmaceuticals, personal care products, and other detergents. Such surfactants should exhibit low toxicity in mammalian cells. In this study we synthesized a series of alkyl or fluoroalkyl β-xylopyranosides from azides and an alkyne(More)
Protein adsorption and interactions with mesoporous silica are of interest for a broad range of applications including drug delivery, chemical synthesis, biosensors, and bioseparations. A major challenge in designing mesoporous silica supports for tailored protein interaction is the differentiation of protein interactions at the surface of the particle from(More)