A 'Sleeping Trojan Horse' which transports metal ions into cells, localises in nucleoli, and has potential for bimodal fluorescence/PET imaging

A rhenium polypyridine-based molecular vessel is membrane impermeant when empty, but, upon loading with metal ions, the cationic form is taken up by MCF-7 cells, localising in nucleoli. The luminescence of the vessel and its copper binding ability suggest potential as a bimodal fluorescence/PET imaging agent.     

Biologically compatible, phosphorescent dimetallic rhenium complexes linked through functionalized alkyl chains: syntheses, spectroscopic properties, and applications in imaging microscopy

A range of luminescent, dimetallic complexes based upon the rhenium fac-tricarbonyl diimine core, linked by aliphatic chains of varying lengths and functionality, have been synthesized and their photophysical properties examined. Each complex displays characteristic (3)M(Re)L(diimine)CT emission in aerated acetonitrile solution, with long lifetimes in the range of 129-248 ns and corresponding quantum yields in the range 3.2-8.0%. In aqueous solution, as opposed to acetonitrile, the complexes generally show a small hypsochromic shift in λ(em) and an extension of the (3)MLCT lifetime, attributed to a hydrophobically driven association of the alkyl chains with the rhenium-bound diimine units. In live cell imaging experiments using MCF7 cells the complexes all show good uptake by non-energy dependent mechanisms without endosomal entrainment, and with varying propensity to localize in organelles. The degrees of uptake and localization properties are discussed in terms of the length and chemical nature of the linkers, and in terms of the likely interactions between these and the various cellular components encountered.     

Damage and ablation of large bandgap dielectrics induced by a 46.9 nm laser beam

We applied a 0.3 mJ, 1.7 ns, 46.9 nm soft-x-ray argon laser to ablate the surface of large bandgap dielectrics: CaF2 and LiF crystals. We studied the ablation versus the fluence of the soft-x-ray beam, varying the fluence in the range 0.05-3 J/cm2. Ablation thresholds of 0.06 and 0.1 J/cm2 and ablation depths of 14 and 20 nm were found for CaF2 and LiF, respectively. These results define new ablation conditions for these large bandgap dielectrics that can be of interest for the fine processing of these materials.     

Pseudo five-component synthesis of bis-α-acyloxy-β-diketo amides from diimide-dicarboxylic acids

Diimide-dicaboxylic acids derived from condensation of α-amino acids with the 2,3,5,6-bicyclo[2.2.2] oct-2-enetetracarboxylic-2,3:5,6-dianhydride or 1,2,4,5- bezenetetracarboxylic-1,2:4,5-dianhydride react with ninhydrin and isocyanides to produce some novel interesting bis-α-acyloxy-β-diketo amides.     

Dominant role of dielectronic satellites in the radiation spectra of a laser plasma near the target surface

It is shown that in a dense, not very hot, multiply charged plasma the satellite structures of resonance lines can become more intense than the resonance lines themselves. Experimental and theoretical investigations show that the conditions under which the satellite structures dominate in the emission spectrum of the plasma are quite easily realized experimentally and, furthermore, apparently they will be the most typical case in investigations of compressed plasma regions in inertial-confinement fusion experiments and in the study of plasma produced by high-contrast pico-and femtosecond laser pulses. Pis’ma Zh. éksp. Teor. Fiz. 65, No. 9, 679–684 (10 May 1997)     

The generation of fast particles in plasmas created by laser pulses with different wavelengths

By means of spatially resolved high-resolution X-ray spectroscopy, we have investigated the generation of fast ions at various laser installations with different flux densities and laser wavelengths. It is demonstrated that the fast ion generation in laser-produced plasma can be achieved for a very low level of the averaged laser intensity on the target. The time-of-flight mass spectrometry ion diagnostics and X-ray spectrographs give very close results for the energy distribution of the thermal ion component. For higher energies, however, we found significant differences: the spatially resolved high-resolution spectrographs expose the presence of suprathermal ions, while the time-of-flight method does not. Suprathermal ion energies E _ion plotted as a function of the qλ² parameter show a large scatter far above the experimental errors. The cause of these large scatters is attributed to a strong nonuniformity of the laser intensity distribution in the focal spot. The analysis by means of hydrodynamics and spectral simulations show that the X-ray emission spectrum is a complex convolution from different parts of the plasma with strongly different electron density and temperature. It is shown that the highly resolved Li-like satellite spectrum near Heαcontains significant distortions even for very low hot electron fractions. Non-Maxwellian spectroscopy allows determination of both the hot electron fraction and the bulk electron temperature.     

Nicotine-related impurities in e-cigarette cartridges and refill e-liquids

The nicotine used in e-cigarettes and refill e-liquids is extracted from tobacco, and its purity can vary depending upon manufacturer and grade. The US and European Pharmacopoeias make recommendations for the purity of nicotine intended for pharmaceuticals; however, there is no official purity recommendation for nicotine used in e-cigarettes. To date, there are few published reports on nicotine-related impurities in e-cigarettes and refill e-liquids. The objective of this work was to develop a sensitive, selective, and robust analytical method for the quantitation of nicotine-related impurities in e-vapor products and to evaluate the nicotine-related impurities in a variety of commercial e-cigarette cartridges (n?=?10) and refill e-liquids (n?=?10). Nicotine-N-oxide, nornicotine, mysomine, and cotinine were observed to increase with time during stability studies. This method was also applied to estimate the transfer efficiency of nicotine-related impurities to the aerosol. Most of the impurities were observed to transfer efficiently. However, nicotine-N-oxides showed low transfer efficiency and demonstrated thermal degradation. This selective and sensitive method is suitable to provide quantitative data for risk assessments and for use in e-cigarette product and refill e-liquid stability studies as one of the stability-indicating measures.     

Non-ablative capillary z-pinch for plasma-based waveguide

The conditions for the formations of plasma-based waveguide in non-ablative argon-filled capillary discharge are studied theoretically. The pinch dynamics is simulated using magneto-hydrodynamic code originally developed and utilized to find proper conditions for operation of capillary-discharge Ar⁺⁸ soft x-ray laser. The presented results show that the ablation-free capillary z-pinch provides conditions that are suitable for guiding of high-intensity laser pulses on the earlier stages of the plasma compression.