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In this paper, the development of efficient protective clothing against nanoparticulate aerosols is presented. Nanofibrous mats of polyamide 6 (PA6) were deposited onto a nonwoven viscose substrate by electrospinning technique. The influence of electrospinning parameters, including solution concentration, viscosity, and conductivity, was studied for the production of nonwovens with controlled fiber diameter showing a size distribution ranging from 66 to 195 nm. By varying several process parameters, textiles with different thickness of the nanofiber layer and thus air permeability were obtained. A hot-press lamination process using a thermoplastic resin as glue was applied to improve the adhesion of the nanofiber layer onto the textile support. After 1500 cycles of repeated compression and torsion, the nanofiber layer was still firmly attached to the support, while mechanical damage is visible in some areas. The penetration of NaCl particles with diameter ranging from 15 to 300 nm through the electrospun textiles was found to be strongly dependent on nanofiber layer thickness. A really thin nanofiber coating provides up to 80% retention of 20 nm size particles and over 50% retention of 200 nm size nanoparticles. Increasing the thickness of the nanofiber mat, the filtration efficiency was increased to over 99% along the whole nanoparticle range. The results obtained highlight the potential of nanofibers in the development of efficient personal protective equipments against nanoparticles.

Nowadays, hundreds of consumer products contain metal and metal oxide nanoparticles (NP); this increases the probability of such particles to be released to natural waters generating a potential risk to human health and the environment. This paper presents the development of efficient carboneous nanofibrous membranes for NP filtration from aqueous solutions. Free-standing carbon nanofiber (CNF) mats with different fiber size distribution ranging from 126 to 554 nm in diameter were produced by electrospinning of polyacrylonitrile (PAN) precursor solution followed by thermal treatment. Moreover, tetraethoxyorthosilicate was added to provide flexibility and increase the specific surface area of the CNF. The resulting membranes are bendable and mechanically strong enough to withstand filtration under pressure or vacuum. The experimental results of filtration revealed that the fabricated membranes could efficiently reject nanoparticles of different types (Au, Ag, and TiO2) and size (from 10 to 100 nm in diameter) from aqueous solutions. It is worth mentioning that the removal of Ag NP with diameters as small as 10 nm was close to 100% with an extremely high flux of 47620 L m−2 h−1 bar−1.

Dithioether- or diamine-tethered adenine derivatives react with Pt(II), Pd(II), and Rh(III) ions to give N3-coordinated complexes of the types [MCl(SSN)](+) (M = Pt or Pd), [RhCl(3)(SSN)], or [RhCl(3)(NNN)] (where SSN = 1-(N9-adenine)-3,6-dithia-heptane or 1-(N9-adenine)-4,7-dithia-octane; NNN = ethylenediamine-N,9-ethyladenine). Single-crystal X-ray analysis confirms the nature of the metal-nucleobase interaction and highlights a conserved intermolecular hydrogen-bonding motif for all the complexes, irrespective of the metal-ion geometry. Coordination significantly reduces the basicity of the adeninyl group, as indicated by a pK(a) value of -0.16 for [PtCl(N3-1-(N9-adenine)-3,6-dithia-heptane)]BF(4), compared to a pK(a) value of 4.2 for 9-ethyladenine. The site of proton binding, N1 or N7, could not be unambiguously assigned from the (1)H NMR data, because of the similar effect on the chemical shifts of the H2 and H8 protons. Density functional calculations at the BP-LACVP level suggest N1 as the site of protonation for this type of complex. This is in contrast to the N7-protonation reported for [Pt(dien)(N3-6,6',9-trimethyladenine)](2+), as reported elsewhere (Meiser et al., Chem.-Eur. J. 1997, 3, 388). However, further electronic structure calculations in the gas phase reveal that the preferred site for protonation for N3-bound complexes is conformationally dependent. N3 coordination was also found to reduce the extent of base pairing between adenine and thymine in dimethylsulfoxide for the self-complementary complex [PtCl(L3)](+) (L3 = 1-(N9-adenine)-3,6-dithia-9-(N1-thymine)nonane), compared to that for the uncomplexed ligand.

A novel oxygen selective highly hydrophobic membrane is prepared by non-solvent induced phase separation in which a dextrin-based nanosponge is incorporated into a poly(vinylidene fluoride co-hexafluoropropylene) (PVDF-HFP) matrix. The membrane presents high capability to entrap moisture from air as well as good hydrophobic behaviour. The membrane was assembled in a pouch type Li-air cell, which was cycled in a galvanostatic mode at curtailed capacity, in air with 17% relative humidity (RH). Owing to the protection of the membrane, the Li-air cell was able to discharge and re-charge for approximately 145 cycles, which correspond to about 1450 h of cell operation.