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The monomer and dimmer acetonitrile anions are examined in order to understand the unusual electronic structure of these species. The atoms in molecules (AIM) analysis has shown the topological variety of the excess electron interacting with acetonitrile molecules, which has manifested itself as charge concentrations, pseudo-atoms and covalent bonds.

Molecular beacon (MB) DNA probes, containing 1-4 pyrene monomers on the 5' end and the quencher DABCYL on the 3' end, are used for real-time probing of DNA sequences. The additional pyrene monomer has resulted in substantial increases in the excimer emission intensities, quantum yields and excited-state lifetimes of the hybridized MBs.

The femtosecond pump-probe spectroscopic study results for the electronic structure and dynamics of isolated adenine, thymine dimers and the adenine-thymine base pair are presented. The observation from the photoelectron spectra indicate short-lived [pi][pi]* and n[pi]* perturbed populations in the hydrogen-bound dimers as compared to the monomers.

A set of monolithic stationary phases representing a broad span of monomers and porogens have been characterized directly in their capillary chromatographic format by computational assessment of their pore structure from transmission electron micrographs obtained after in situ embedment of the monoliths in contrast resin, followed by dissolution of the fused-silica tubing, further encasement of the resin-embedded monolith, and microtomy. This technique has been compared to mercury intrusion, a more conventional technique for macroporosity estimation. Supplementing the embedding resin by lead methacrylate gave a negative staining, and the resulting micrographs showed a good contrast between the polymeric monoliths and the embedding resin that allowed studies on the pore formation and polymer development. The technique was also applied to a commercial monolithic silica column.

The role of N-terminus and its microenvironment is examined in determining enzyme stability and catalysis using human placental alkaline phosphatase (PLAP) and tissue-nonspecific alkaline phosphatase (TNAP) as examples. Results reveal that N-terminal alpha-helical folding is very important for structural stability of second monomer in TNAP than in PLAP.

In this report, we introduce a new entry of high-performance polymer-based monolithic capillary column for mainly small molecules. This capillary column was prepared using a newly introduced epoxy monomer with diamines. Simply heat-induced polycondensation in an appropriate porogenic solvent afforded a really homogeneous co-continuous monolithic structure having submicrometer-size skeletons with micrometer-size throughpores. We were also able to prepare chiral monolithic columns using a chiral epoxy monomer as well as a chiral diamine. A 21.5-cm-long, 100-[micro]m-i.d. column afforded up to 40 000 theoretical plate numbers (N) for alkylbenzenes in 60% aqueous acetonitrile as a reversed-phasemode stationary phase. Due to a quite low column pressure drop, a 150-cm-long column was prepared. This long column afforded up to 200 000 plates for alkylbenzenes with only a 4-MPa column pressure drop. In contrast, in 100% acetonitrile, this column has 'HILIC' property to show up to 60 000 plates for methanol with a 17.5-cm-long column. In this mode, we were able to separate nucleic acids. In addition, we have prepared a chiral column with both of the chiral epoxy monomers and an amine. This column was able to chirally discriminate a racemic alcohol in a reversed-phase mode.

We present a robust and simple method for direct, label-free PCR product quantification using an integrated microelectronic sensor. The field-effect sensor can sequentially detect the intrinsic charge of multiple unprocessed PCR products and does not require sample processing or additional reagents in the PCR mixture. The sensor measures nucleic acid concentration in the PCR relevant range and specifically detects the PCR products over reagents such as Taq polymerase and nucleotide monomers. The sensor can monitor the product concentration at various stages of PCR and can generate a readout that resembles that of a real-time fluorescent measurement using an intercalating dye but without its potential inhibition artifacts. The device is mass-produced using standard semiconductor processes, can be reused for months, and integrates all sensing components directly on-chip. As such, our approach establishes a foundation for the direct integration of PCR-based in vitro biotechnologies with microelectronics.

Aiming at enhancing the advantages of traditional molecularly imprinted polymers (MIPs) for chemical sensing, a new MIP design approach introducing an internal heavy atom in their polymeric structure is described. Based on the heavy-atom effect, the novel polymer allows one to perform room-temperature phosphorescence (RTP) transduction of the analyte. The synergic combination of a tailor-made MIP recognition with a selective RTP detection is a novel concept for optosensing devices which is assessed here for simple and highly selective determination of trace amounts of fluoranthene in water. The noncovalent MIP was synthesized using the laboratory-synthesized tetraiodobisphenol A as one of the polymeric precursors and fluoranthene as template. In the presence of an oxygen scavenger, the iodide included in the polymeric structure induced efficient RTP emission from the analyte, once recognized by the MIP. The developed optosensing system has demonstrated a high specificity for fluoranthene against other polycyclic aromatic hydrocarbons. Detection limit for the target molecule was 35 ng/L (5-mL sample injections), and the linear range extended above 100 [micro]g/L of the analyte. The polymer can be easily regenerated for subsequent sample injections (at least up to 450 cycles) with acetonitrile. The synthesized sensing material showed good stability for at least 6 months after preparation. The feasibility of monitoring fluoranthene in real samples was successfully evaluated through the analysis of five spiked fiver water samples.

Ionic liquids (ILs) are a class of nonmolecular solvents in which the cation/anion combination can be easily tuned to provide desired chemical and physical properties. When used as stationary phases in gas-liquid chromatography, ionic liquids exhibit dual nature retention selectivity. That is, they are able to separate polar molecules such as a polar stationary phase and nonpolar molecules such as a nonpolar stationary phase. However, issues such as optimization of the wetting ability of the ionic liquid on fused-silica capillaries, the maximum operating temperatures of the stationary phases, and nonuniform film thickness on the wall of the capillary at high temperatures have limited their use in gas chromatography. As described in this paper, these limitations are overcome by cross-linking a new class of ionic liquid monomers by free radical reactions to provide a more durable and robust stationary phase. By lightly cross-linking the ionic liquid stationary phase using a small amount of free radical initiator, high-efficiency capillary columns were produced that are able to endure high temperatures with little column bleed. Two types of cross-linked IL stationary phases are developed. A partially cross-linked stationary phase allows for high-efficiency separations up to temperatures of ~280[degrees]C. However, by creating a more highly cross-linked stationary phase of geminal dicationic ILs, exclusively, an increase in efficiency is observed at high temperatures allowing for its use over 350[degrees]C. In addition, through the use of solvation thermodynamics and interaction parameters, it was shown that the cross-linking/immobilization of the ionic liquid does not affect the selectivity of the stationary phase thereby preserving its dual nature retention behavior.

The possibility of using triynes [R(C triple bond CH)3] as monomer units to assemble hyperbranched polyynes is explored. A group of hyperbranched polyynes (hb-PYs) is prepared through structural design and reaction control, which are soluble, emissive, refractive, thermally curable, peripherally functionalizable, and molecularly metallizable.

First through fourth generation (G1-G4) dendronized macromonomers with a methyleneoxycarbonyl spacer between the polymerizable group and dendritic side chain (dendron) were synthesized, and their polymerization behavior to the dendronized polymers were investigated by heating the monomers to 55 degree C without intentional addition of initiator. Both structure and dynamics were investigated by DSC, X-ray diffraction, and dynamic mechanical measurements.

The total synthesis of the lichen-derived antitumor agent hybocarpone and related compounds are studied. Direct access to the hybocarpone skeleton is possible by oxidative dimerization of the corresponding naphthazarin monomer employing CAN as the oxidant.

Measurements of chemical exchange events in the crystalline polycarbonate monomer 4,4'-isopropylidenediphenol (bisphenol A, BPA) via 2D 13C solid-state NMR shows slow, large-amplitude aromatic ring orientations. Experiments with multiple exchange times show that ring flips occur in all of the three unique conformers found in the crystalline unit cell of this compound, but in specific cases, two of the three unique molecules actually switch conformations.

Full account of the total synthesis and absolute stereo chemical assignment of (+)-torreyanic acid is reported. Thermolysis experiments are conducted on a model dimer based on the torreyanic acid core structure and facile retro Diels-Alder reaction processes and equilibration of diastereomeric 2H- pyrans is observed.

The changes in the structural, vibrational, bonding, and electronic properties of small clusters of the group III nitrides when an electron is added to the neutral clusters are described. The atomic charge analysis suggests that the added electron is located over the metallic atoms in dimers and trimers and equally shared by metal and nitrogen atoms in monomers.

The monomer radical and the dimer radical cation of cyanopyridinium derivatives was studied by absorption and electron spin resonance (ESR) spectroscopies at room temperature. The results indicated that the formation of monomer radicals and dimer radical cations from the same cyanopyridinium cations by photoinduced electron transfer in acetonitrile (ACN) at room temperature.

The ultrafast fluorescence up-conversion behaviors of a series of hemicyanine dyes, including monomer and dimmers, are studied. The fluorescence decay curves of these dyes can be well fitted by the sum of several exponential decays in the shorter wavelengths and by the sum of the exponential rises with decays in the longer wavelengths.

Research has been conducted on the aldose reductase (AR), a NADPH-dependent enzyme causing diabetic complications. The results of the interactions of R- and S-isomers with AR under physiological conditions in the attempt to elucidate the inhibition modes are discussed.

Research has been conducted on eotaxin-3 which activates chemokine receptor CCR3. The 3D structure and backbone dynamics of eotaxin-3 that have been determined by NMR spectroscopy are described.

Research has been conducted on the phospholipids hydrolysis by class II phospholipase A (sub)2 (PLA (sub)2) which involves a Ca (super)2+ ion cofactor. The effect of pH on the monomer-dimer equilibrium of Lys49-PLA (sub)2 from the Bothrops jararacussu venom has been investigated.

Research has been conducted on the dimeric Crotalus atrox venom phospholipase. The study of the monomer-dimer equilibrium of the C. atrox venom in solution in the presence of urea and monomeric phosphatidylcholine analogue has been carried out via fluorescence correlation spectroscopy.

Research has been conducted on the monomeric titanocene(III) complex Cp (sub)2 TiPh. The use of this complex in investigating the catalyzed inter- and intramolecular pinacol couplings is discussed.

An interface appeared during the polymerization to form heterogeneous structures in the vicinity of the hydrophobic substrates when a hydrogel was polymerized from its vinyl monomer in water. This substrates effect was found to have a correlation with the surface tension of the hydrophobic surface.

Research is presented concerning the investigation of chromophore aggregation and phenyl group rotation in poly- and oligo-(phenyleneethynylene)s through the use of semiempirical calculations and photophysical measurements.

Individual NO monomers, with adsorption at 4-65K and at low coverages, are imaged at 4K and appear as depressions in the STM images. The low barrier to diffusion, together with its appearance in STM, proves that monomer is weakly chemisorbed.

It has been possible to identify a complex kinetic rate law in a catalytic reaction network where the active monomeric species is in equilibrium with a dimer species. The rate constants can be estimated in cases where transitions between dominant terms in the reaction rate law arise.

Spectroscopic investigations on structure and dynamics of 9(10H) -acridone (AD) and its hydrated clusters were performed. The monomer band in the FE spectrum is extremely weak implying small fluorescence quantum yield; while the cluster bands are stronger hence the quantum yield is more.

A synthesis made of a protected form of (R,R,R,)-2,5-diaminocylohexanecarboxylic acid (DCHC), a monomer, to enable a study of 14-helix formation by short beta-peptides in a water solution is presented. An improved synthesis of protected versions of ACHC itself is also reported.

Research has been conducted on the structure formation and dimerization in the Arc repressor refolding. The investigation of the secondary structure integrity in the Arc refolding transition state has been carried out.

It is possible to systematize experimental data on CO2 frequency shifts obtained for different vibrational modes using a correlation with the square root of the critical temperature. The use of the correlations identified in this research allows an indication of some intervals in which the host material critical temperature can be anticipated.

Research into the energetics of gas-phase tautomerization of both monomers and dimers of the 4-pyridinol and 4(1H)-pyridinone molecules is presented. The hydrogen-bond energies show a strong preference for 4(1H)-pyridinon-containing dimers.

High-frequency voltage pulses at a microelectrode are used to evaluate solution electrogenerated chemiluminescence for molecules of interest for organic light-emitting diodes.

Research has been conducted on the on the quinuclidine-stabilized amido- and azidogallanes. The synthesis of these compounds from the mono- and dichlorogallane quinuclidine adducts is described.

A new study uses gas-phase electron diffraction and quantum chemical studies to investigate the molecular geometry of monomeric and dimeric gold trifluoride.

Research has been conducted on the CC chemokine structures. The use of nuclear magnetic resonance spectroscopy in analyzing the mutants' oligomeric state is described.

A promising new type of monomer in the P-stereospecific synthesis of PS-ODNs has been found in deoxyribonucleoside cyclic N-acylphosphoramidites such as Rp-1 and Sp-1.

Research has been conducted on the TATA-binding protein (TBP). The role of TBP dimerization in transcriptional initiation regulation is discussed.

Research is presented demonstrating the use of 15N, 7Li, 13C and 29Si nuclear magnetic resonance spectroscopy to study the solution structures of three [(Amino)phenylsilyl]lithiums.

Research has been conducted on the precursor route development to poly(p-phenylenevinylene) derivatives. The use of p-xylene derivatives that possess a benzylic sulfinylalkyl group is discussed.

Research has been conducted on the equilibrium between active dimers and inactive monomers. Experiments indicate that monomers dimerization and dimers dissociation processes can be controlled.

A study concerning the preparation of 9-phenylcarbazole ethynylene monodendrons is presented. The results of the palladium-catalyzed coupling reactions are discussed.

A combination of static and dynamic methodologies has been used to investigate the free energy surface of the monomer capture process for Brookhart's Ni(II) olefin polymerization catalyst, (ArN=C(R')-C(R')=NAr)NiII-R+. It was established that there is no enthalpic barrier to the capture process.

Research is presented describing the preparation, crystallization, and solid-state characterization, of a spiro-biphenalenyl radical which is monomeric in the solid state. Curie behaviour (1 spin per molecule) occurs throughout a 10-400 Kelvin temperature range.

Research concerning the ability of polycytidylate to direct and catalyze the synthesis of oligoguanylates from guanosine 5'-phosphate 2-methylimizadolide is discussed. Results demonstrate that small amounts of isomeric dimers are formed slowly in the absence of poly(C).

An enzyme-mediated kinetic resolution method was used to create for the first time an enantiomerically pure indane monomer. This will lead to the production of polymers with enhanced nonlinear optical properties.

Several new methods have been developed for the preparation of highly functionalized pyrazines by employing bis(Curtius) rearrangements and dilithiation reactions via directed di(ortho-metalation) processes. A convergent strategy for the production of pyrazine polymers, where both the A and B components for a condensation polymerization arose from electron deficient systems, is presented. As expected, the planarization induced optical band gap decreases in the highly conjugated systems.

Fluorescence spectroscopy and electron paramagnetic resonance spectroscopy were used to investigate the effect of the replacement of ATP with ADP on the dynamic and conformational properties of the actin monomer. Results showed that the exchange of ATP for ADP induced at least two distinct types of conformational changes in the actin monomer. One was a rapid change where the Gln-41 and Cys-374 residues came closer together while the other was a slower change that could still be detected several hours after the start of the nucleotide exchange.

A synthesis of five reduced polyoxomolybdate anions is presented. The use of IR spectroscopy, hydrothermal reactions and redox titrations is described.

Research has been conducted on the (super)1 H NMR spectra line broadening. The thermodynamic and kinetic parameters of the diamagnetic dimer dissociation into the paramagnetic monomers are presented.

The syntheses of thiophene monomers possessing strongly redox-active substituents were examined via the electron-donating tetrathiafulvalene and the electron-accepting fluorene unit. The materials are highly suitable precursors toward fascinating electroactivev molecular species and conducting polymers incorporating strong redox active units. An investigation into the reactivity and electrochemistry of the thiophene systems is being conducted.