Hydrophobic sand is a relatively new method of urine collection in the rodent, comparable to the established method using a metabolic cage. Urine samples are often used in rodent research, especially for biomarkers of health changes after internal contamination from embedded metals, such as in a model of a military shrapnel wound. However, little research has been done on the potential interfer...

This paper combines new experimental data for electrokinetic characterization of hydrophobic polymers with a detailed discussion of the putative origins of charge at water-hydrophobe interfaces. Complexities in determining the origin of charge are discussed in the context of design and modeling challenges for electrokinetic actuation in hydrophobic microfluidic devices with aqueous working flui...

Water adsorption isotherms are calculated by grand canonical Monte Carlo simulations for the SPC/E water model in carbon nanopores at 298K. The pores are of slit or cylindrical morphology. Carbon-slit pores are of widths 0.8, 1.0 and 1.6 nm. The simulated single-walled carbon nanotubes are of 1.4 and 2.7 nm diameter ((10:10) and (20:20) respectively). In all cases considered, the adsorption iso...

The pendant-drop method (with drop-shape analysis) and Langmuir trough are applied to investigate the characteristic relaxation times and elasticity of interfacial layers from the protein HFBII hydrophobin. Such layers undergo a transition from fluid to elastic solid films. The transition is detected as an increase in the error of the fit of the pendant-drop profile by means of the Laplace equa...

We have synthesized a microporous magnetic framework that contained supertetrahedral decametallic cobalt clusters as nodes and 4-(tris(hydroxymethyl)methyl)pyridine ligands as linkers in a NaCl-like network. This complex shows canted antiferromagnetism with spin-glass behavior. After the removal of the guest molecules, the spin-canting and spin-glass behaviors are maintained. The permanent poro...

Experimental evidence suggests that proteins adsorbed to hydrophobic surfaces at low coverages are stabilized relative to the bulk. For larger coverages, proteins unfold and form beta-sheets. We performed computer simulations on model proteins and found that: 1), For weakly adsorbing surfaces, unfolded conformations lose more entropy upon adsorption than folded ones. 2), The melting temperature...

The impact of membrane fouling by natural organic matter (NOM) on the behavior of micropollutants during ultrafiltration (UF) was investigated. Batch experiments with radioactively labeled estradiol and ibuprofen in the presence of NOM model compounds (alginate, Nordic aquatic and Aldrich humic acid) were performed using a hydrophilic and a hydrophobic membrane. The results indicate that the im...

Rheological measurements in biological liquids yield insights into homeostasis and provide information on important molecular processes that affect fluidity. We present a fully automated cantilever-based method for highly precise and sensitive measurements of microliter sample volumes of human blood plasma coagulation (0.009 cP for viscosity range 0.5-3 cP and 0.0012 g/cm3 for density range 0.9...

Siderophore-promoted iron acquisition by microorganisms usually occurs in the presence of other organic molecules, including biosurfactants. We have investigated the influence of the anionic surfactant sodium dodecyl sulfate (SDS) on the adsorption of the siderophores DFOB (cationic) and DFOD (neutral) and the ligand EDTA (anionic) onto goethite (alpha-FeOOH) at pH 6. We also studied the adsorp...