The alkali metal ion affinity of guanine quadruplexes has been studied using dispersion-corrected density functional theory (DFT-D). We have done computational investigations in aqueous solution that mimics artificial supramolecular conditions where guanine bases assemble into stacked quartets as well as biological environments in which telomeric quadruplexes are formed. In both cases, an alkal...

Abstract The regulation of anions and cations at the atomic scale is great significance in membrane-based separation technologies. Ionic transport techniques could also play a crucial role developing high-performance alkali metal batteries such as metal-sulfur metal-selenium batteries, which suffer from non-uniform ions (e.g., Li + or Na ) detrimental shuttling effect polysulfide/polyselenide a...

Macrocyclic compounds like crown ethers, calixarenes, etc. are well explored in the literature as receptors for alkali metal ions. In most of these studies, the size of the macrocyclic cavity has evolved as the prominent determining criterion for the selective binding of various ions. However, approaches to systematically tailor the ion transport properties via the interplay of topological as w...

We have performed measurements of the spatial distribution of current in various alkali and reactive ion beams over the energy range 5–600 eV using a Faraday cup. Ion beam current densities have been extracted from these measurements using a simple deconvolution procedure. Our results reveal that the beams are Gaussian in shape with a constant width, s , for energies greater than approximately ...

A PVC-membrane ion-selective electrode was constructed for quantitative monitoring of gadolinium(III) ion based on 3-methyl-1H-1,2,4-triazole-5-ylhydrosufide (MTY) as an ion carrier. The electrode performance includes a Nernstian slope of 19.8 ± 0.4 mV per decade across a wide concentration range between 1.0 × 10 and 1.0 × 10 M and a detection limit of 7.3 × 10 M. The best performance was obtai...

We have studied the block of potassium channels in voltage-clamped squid giant axons by nine organic and alkali cations, in order to learn how the channel selects among entering ions. When added to the internal solution, all of the ions blocked the channels, with inside-positive voltages enhancing the block. Cesium blocked the channels from the outside as well, with inside-negative voltages fav...

The pyridoxal 5'-phosphate-dependent enzyme dialkylglycine decarboxylase (DGD) is activated by K+ and Rb+ ions, whereas Li+ and Na+ ions are inhibitory. A binding site for alkali metal ions close to the active site (site 1) was discovered in the crystal structure of DGD, and an exchange of K+ for Na+ at this site was shown to affect the conformation of two active site residues [Toney, M. D., Ho...

This paper reports on the ion fluxes at interfaces of various porous carbon electrodes/aqueous solutions alkali metal cations (Na+, K+ and Rb+) iodide anions, monitored by an electrochemical quartz crystal microbalance (EQCM).