UV-induced bursting of cell-sized multicomponent lipid vesicles in a photosensitive surfactant solution.

We study the behavior of multicomponent giant unilamellar vesicles (GUVs) in the presence of AzoTAB, a photosensitive surfactant. GUVs are made of an equimolar ratio of dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) and various amounts of cholesterol (Chol), where the lipid membrane shows a phase separation into a DPPC-rich liquid-ordered (L(o)) phase and a DOPC-rich liquid-disordered (L(d)) phase. We find that UV illumination at 365 nm for 1 s induces the bursting of a significant fraction of the GUV population.

Revised ionic radii of lanthanoid(III) ions in aqueous solution.

A new set of ionic radii in aqueous solution has been derived for lanthanoid(III) cations starting from a very accurate experimental determination of the ion-water distances obtained from extended X-ray absorption fine structure (EXAFS) data. At variance with previous results, a very regular trend has been obtained, as expected for this series of elements. A general procedure to compute ionic radii in solution by combining the EXAFS technique and molecular dynamics (MD) structural data has been developed.

Stability and instability of the isoelectronic UO2(2+) and PaO2+ actinyl oxo-cations in aqueous solution from density functional theory based molecular dynamics.

In this work, Pa(V) monocations have been studied in liquid water by means of density functional theory (DFT) based molecular dynamic simulations (CPMD) and compared with their U(VI) isoelectronic counterparts to understand the peculiar chemical behavior of Pa(V) in aqueous solution. Four different Pa(V) monocationic isomers appear to be stable in liquid water from our simulations: [PaO(2)(H(2)O)(5)](+)(aq), [Pa(OH)(4)(H(2)O)(2)](+)(aq), [PaO(OH)(2)(H(2)O)(4)](+)(aq), and [Pa(OH)(4)(H(2)O)(3)](+)(aq). On the other hand, in the case of U(VI) only the uranyl, [UO(2)(H(2)O)(5)](2)(+)(aq), is stable.