Patrick G Hartley

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PURPOSE The role of fine lactose in the dispersion of salmeterol xinafoate (SX) from lactose mixtures was studied by modifying the fine lactose concentration on the surface of the lactose carriers using wet decantation. METHODS Fine lactose was removed from lactose carriers by wet decantation using ethanol saturated with lactose. Particle sizing was(More)
The prevalence of infections caused by multidrug-resistant gram-negative Acinetobacter baumannii strains and the lack of novel antibiotics under development are posing a global dilemma, forcing a resurgence of the last-line antibiotic colistin. Our aim was to use atomic force microscopy (AFM) to investigate the morphology and topography of paired(More)
We present studies of the delivery of short interfering ribonucleic acid (siRNA) into a green fluorescent protein (GFP) expressing cell line, using lipid nanocarriers in cubic lyotropic liquid crystal form. These carriers are based on glycerol monooleate (GMO) and employ the use of varying concentrations of cationic siRNA binding lipids. The essential(More)
BACKGROUND The nuclear weapons industry has long been known as a source of beryllium exposure. METHODS A total of 1,004 former workers from a nuclear weapons assembly site in the Midwest were screened for sensitization to beryllium (BeS). The screenings were part of the Department of Energy (DOE) Former Worker Program established in 1996. RESULTS(More)
We show for the first time the possibility of using networks of amyloid fibrils, adsorbed to solid supports and with plasma polymer coatings, for the fabrication of chemically homogeneous surfaces with well-defined nanoscale surface features reminiscent of the topography of the extracellular matrix. The robust nature of the fibrils allows them to withstand(More)
Adhesion force distributions of silica spheres (5 and 20 microm) and salmeterol xinafoate (4 microm) particles with inhalation grade lactose surfaces and spin coated lactose films were determined by atomic force microscopy (AFM) to investigate the influence of surface roughness on the force distributions. The roughness of lactose particles and films was(More)
This work reports the self-assembly of a sparingly soluble antibiotic (ciprofloxacin) and a hydrophobic tripeptide ((D)Leu-Phe-Phe) into supramolecular nanostructures that yield a macroscopic hydrogel at physiological pH. Drug incorporation results in modified morphology and rheological properties of the self-assembled hydrogel. These changes can be(More)
Change of chirality is a useful tool to manipulate the aqueous self-assembly behaviour of uncapped, hydrophobic tripeptides. In contrast with other short peptides, these tripeptides form hydrogels at a physiological pH without the aid of organic solvents or end-capping groups (e.g. Fmoc). The novel hydrogel forming peptide (D)Leu-Phe-Phe ((D)LFF) and its(More)
Hydrogels formed by ultrashort peptides are emerging as cost-effective materials for cell culture. However, L-peptides are labile to proteases, while their D-isomers are thought to not support cell growth as well. In contrast, the self-assembly behaviour and biological performance of heterochiral peptides (i.e., made of both d and l amino acids) are largely(More)
Change of chirality of the first N-terminal amino acid of tripeptides VFF and FFV from l to d results in self-assembled hydrogels at physiological pH from non-assembling l-analogues. Interestingly, changing the chirality of F yields very different nanostructures; nanotapes are observed for (D)VFF, twisted fibers for (D)FFV.