Protein Transport upon Advection at the Air/Water Interface: When Charge Matters.

The formation of dense protein interfacial layers at a free air-water interface is known to result from both diffusion and advection. Furthermore, protein interactions in concentrated phases are strongly dependent on their overall positive or negative net charge, which is controlled by the solution pH. As a consequence, an interesting question is whether the presence of an advection flow of water toward the interface during protein adsorption produces different kinetics and interfacial structure of the adsorbed layer, depending on the net charge of the involved proteins and, possibly, on the sign of this charge.

Calcium phosphate powder synthesis by out-of-phase pulsed sonoelectrochemistry.

High aspect ratio calcium phosphate (CaP) nanorods were achieved by out-of-phase pulsed sonoelectrodeposition from electrolytic aqueous bath composed of calcium nitrate, ammonium dihydrogenophosphate and surfactant at pH of 4.9. The nature of CaP phases was determined by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR) and energy dispersive X-ray spectroscopy (EDX).

Synthesis of calcium-deficient hydroxyapatite nanowires and nanotubes performed by template-assisted electrodeposition.

Hydroxyapatite (HA) has received much interest for being used as bone substitutes because of its similarity with bioapatites. In form of nanowires or nanotubes, HA would offer more advantages such as better biological and mechanical properties than conventional particles (spherical). To date, no study had allowed the isolated nanowires production with simultaneously well-controlled morphology and size, narrow size distribution and high aspect ratio (length on diameter ratio).

Interfacial properties, film dynamics and bulk rheology: A multi-scale approach to dairy protein foams.

Hypothesis: The effective contribution of interfacial properties to the rheology of foams is a source of many open questions. Film dynamics during topological T1 changes in foams, essentially studied for low molecular weight surfactants, and scarcely for proteins, could connect interfacial properties to protein foam rheology.

Experiments: We modified whey protein isolate (WPI), and its purified major protein β-lactoglobulin (β-lg) by powder pre-conditioning and dry-heating in order to obtain a broad variety of interfacial properties.