The effect of hydrophilic penetration/diffusion enhancer on stratum corneum lipid models: Part II*: DMSO.

To optimize dermal and transdermal administration of drugs, the barrier function of the skin, particularly the stratum corneum (SC), needs to be reduced reversibly. For this purpose, penetration/diffusion enhancers such as DMSO can be applied. However, there is the question whether DMSO is an aggressive penetration/diffusion enhancer in pharmaceutical and cosmetical relevant concentrations? Until now, it is unclear if this penetration/diffusion enhancement is caused by an interaction with the SC lipid matrix or related to effects within the corneocytes.

Divergence of the third harmonic stress response to oscillatory strain approaching the glass transition.

The leading nonlinear stress response in a periodically strained concentrated colloidal dispersion is studied experimentally and by theory. A thermosensitive microgel dispersion serves as well-characterized glass-forming model, where the stress response at the first higher harmonic frequency (3ω for strain at frequency ω) is investigated in the limit of small amplitude. The intrinsic nonlinearity at the third harmonic exhibits a scaling behavior which has a maximum in an intermediate frequency window and diverges when approaching the glass transition.

The effect of urea and taurine as hydrophilic penetration enhancers on stratum corneum lipid models.

To optimize transdermal application of drugs, the barrier function of the skin, especially the stratum corneum (SC), needs to be reduced reversibly. For this purpose, penetration enhancers like urea or taurine are applied. Until now, it is unclear if this penetration enhancement is caused by an interaction with the SC lipid matrix or related to effects within the corneocytes.

Localization of trehalose in partially hydrated DOPC bilayers: insights into cryoprotective mechanisms.

Trehalose, a natural disaccharide with bioprotective properties, is widely recognized for its ability to preserve biological membranes during freezing and dehydration events. Despite debate over the molecular mechanisms by which this is achieved, and that different mechanisms imply quite different distributions of trehalose molecules with respect to the bilayer, there are no direct experimental data describing the location of trehalose within lipid bilayer membrane systems during dehydration. Here, we use neutron membrane diffraction to conclusively show that the trehalose distribution in a dioleoylphosphatidylcholine (DOPC) system follows a Gaussian profile centred in the water layer between bilayers.

Small-angle X-ray scattering in droplet-based microfluidics.

Small-angle X-ray scattering (SAXS) is a powerful technique to probe nanometer-scale structures; a particularly powerful implementation of SAXS is to apply it to continuously flowing liquid samples in microfluidic devices. This approach has been employed extensively, but virtually all existing studies rely on the use of one-phase microfluidics. We overcome this limitation and present the combination of SAXS with multiphase, droplet-based microfluidics to establish a platform methodology.