Intracellular calcium concentration in biological cells varies from 0.1 to 10 muM depending upon cell signaling and disease states. A direct estimate of calcium concentration in cell tissues within this range is possible with a novel calcium-selective reagent 15C5-774. The molecule of 15C5-774 consists of a near-infrared (NIR) chromophore (lambda(max)=774 nm) and a metal complexing moiety of be...

A helical 14-residue peptide containing four polar, but uncharged, benzo-21-crown-7 side-chains aligned along one face induces significantly more vesicle leakage than analogous 21-mer or 7-mer peptides.

The quantitative analysis and identification of the radiolytic products of dicyclohexano-18-crown-6 (DCH18C6), 4',4''(5'')-di-tert-butyldicyclohexano-18-crown-6 (DtBuCH18C6) and benzo-18-crown-6 (B18C6) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([C4mim][NTf2]) ionic liquid after irradiation were performed for the first time. It was found that the yield for radiolytic des...

A novel A2-B3-type supramolecular hyperbranched polymer was prepared based on the benzo-21-crown-7/secondary ammonium salt recognition motif. The resulting supramolecular polymer exhibited a reversible disassembled-assembled process by adding or removing potassium ions.

Single 15-crown-5 functionalized Au nanoparticles (NPs) were synthesized with assistance of silica particles. The use of silica particles renders intrinsic advantages in that each step along the product formation can be monitored by, for example, a transmission electron microscope, and large surface-to-volume ratio of silica particles leads to a better yield of Au NP attachment than the glass s...

Calix[4]-bis-2,3-naphtho-crown-6 can be used to discriminate between methylammonium and other organic ammonium ions. An electrode based on this ionophore, potassium tetrakis(p-chlorophenyl)borate (20 mol% relative to the ionophore) as an ionic additive and bis(2-ethylhexyl) sebacate as a solvent mediator in a poly(vinyl chloride) membrane matrix, displayed higher selectivity for methylammonium ...

The novel 4'-(ammoniummethylene)benzo-18-crown-6 cation was synthesized as a hexafluorophosphate salt and found to exist as a cyclophane-like dimer in the solid state, gas phase and in acetonitrile solution.

In this review, we report DNA duplex-based fluorescence probes/sensors using pyrene monomer-excimer switching. The review mainly comprises two topics: 1) excimer-monomer switching molecular beacons (EMS-MB) and 2) monomer-excimer switching sensors based on the structural motif of antibodies. The EMS-MBs have two pyrene fluorophores connected both at 3' and 5' ends of a single-stranded oligonucl...

Reaction of [U(TrenTIPS )(PH2 )] (1, TrenTIPS =N(CH2 CH2 NSiPri3 )3 ) with C6 H5 CH2 K and [U(TrenTIPS )(THF)][BPh4 ] (2) afforded a rare diuranium parent phosphinidiide complex [{U(TrenTIPS )}2 (μ-PH)] (3). Treatment of 3 with C6 H5 CH2 K and two equivalents of benzo-15-crown-5 ether (B15C5) gave the diuranium μ-phosphido complex [{U(TrenTIPS )}2 (μ-P)][K(B15C5)2 ] (4). Alternatively, reaction...