improvement of the Specificity of Surface Plasmon Resonance with BSA-modified Chip

Recently, surface plasmon resonance (SPR) become more and more popular without the need of the label technology1-3. However, sometimes, a number of experimental artifacts complicate the final biosensor analysis4-7. The utilization of a reference surface c…     

Resonance CARS spectra of 9,9′-bianthryl in the excited states

Resonance CARS spectra of 9,9′-bianthryl in the twisted intramolecular charge-transfer (TICT), locally excited (LE)-S₁ and T₁ states were obtained in solution at room temperature. Observed Raman frequencies were compared with those of the S₀ state, the values of anthracene in the S₁, T₁ and radical ion states. The results show those vibrational modes of bianthryl not only in the S₀ state but also in the LE-S₁, TICT and T₁ states more or less consist of those of anthracene moieties. The inter-moiety CC stretching vibrational mode was not observed in the excited states.     

Resonance Raman effect and the structures of the naphthalene—tetrahalophthalic anhydride π-complexes in the triplet state

The triplet state properties of the naphthalene—tetrachlorophthalic (N:TCPA) and naphthalene—tetrabromophthalic (N:TBPA) anhydride π-complex crystals were studied at room temperature using the resonance Raman technique. The RR effect was observed in the triplet charge-transfer states of the two complexes. The heavy-atom effect and charge-transfer complexation are the dominant factors leading to intensity enhancement of donor and acceptor vibrational modes. The relationship between the effect in the complexes and the parent molecules provides evidence for different structures for N:TCPA and N:TBPA in the triplet state. Most probably the N:TCPA complex has the two planar components colinear, with the molecular planes parallel along the molecular axis. The N:TBPA complex probably has the two components bound in such a manner the carbon—bromine bonds are distorted out-of-plane.     

Resonance Rayleigh Scattering Method for the Determination of Raloxifene with Evans Blue

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Resonance of relaxation time in the temperature modulated Schlögl model

We show the possibility to accelerate-in a resonant way-a nonlinear chemical reaction by imposing a small temperature modulation. This classical resonance, which happens for particular modulation frequencies, is illustrated on the athermic cubic Schlogl model, which allows us to get analytical expressions for both the reaction relaxation time and the frequency-resonant delay.     

Resonance effects on the inner-valence levels of SF6 in the photon-energy range 52–72 eV

We report the photoionization partial cross section and asymmetry parameter in the 52–72 eV photon-energy range for the inner-valence orbitais (3t_1u, 2e_g, and 4a_1g) in gaseous SF₆. These results, combined with those for the (inner valence)/(outer valence) branching ratio, indicate resonant enhancement of the inner-valence levels at ≈ 59 eV photon energy which we associate with the 3t_1u → e_g shape resonance predicted by MSM Xα calculations.     

α BB Resonance in the ν8 Band of Borazine –10B

The high-resolution FTIR spectrum of the fundamental ₈ of borazine ¹⁰B₃ ¹⁴N₃ ¹H₆ was reanalyzed taking into account the ^BB resonance with the combination band (₁₀ + ₁₇). A parameter set for the states ₈ = 1 and ₁₀ = ₁₇ = 1, respectively, is given, reproducing the observed spectrum at least up to J = 30 with experimental accuracy.     

Monitoring the Interaction of α-Synuclein with Calcium Ions through Exclusively Heteronuclear Nuclear Magnetic Resonance Experiments

Many properties of intrinsically disordered proteins (IDPs), or protein regions (IDRs), are modulated by the nature of amino acid side chains as well as by local solvent exposure. We propose a set of exclusively heteronuclear NMR experiments to investigate these features in different experimental conditions that are relevant for physiological function. The proposed approach is generally applicable to many IDPs/IDRs whose assignment is available in the Biological Magnetic Resonance Bank (BMRB) to investigate how their properties are modulated by different, physiologically relevant conditions. The experiments, tested on α-synuclein, are then used to investigate how α-synuclein senses Ca²⁺ concentration jumps associated with the transmission of nerve signals. Novel modules in the primary sequence of α-synuclein optimized for calcium sensing in highly flexible, disordered protein segments are identified.     

Resonance Light Scattering Imaging Determination of Heparin

Light scattering submicroscopic particles such as metallic particles and particles of other composition have high-producing power and can be used as fluorescent analogs and tracers labels in clinical and biological applications1-3. Their light scattering …     

Resonance Rayleigh scattering study of the interaction of bleomycinA_5 with nucleic acids and its analytical application

The interaction of bleomycinA5 with nucleic acids has been investigated by using resonance Rayleigh scattering (RRS), molecular absorption and fluorescence spectra. The result shows that in near pH 2.2 buffer medium and absence of any metal ions, nucleic acids are capable of binding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensity and result in batho- chromic and hyperchromic molecular absorption of nucleic acids and fluorescence quenching of bleomycinA5. The RRS spectral characteristics for the binding products of bleomycinA5 with various DNA and RNA are similar, and the maximum RRS peaks are at 301 nm for ctDNA and sDNA, 370 nm for hsDNA, 310 nm for RNAtypeVI and RNAtypeIII, respectively. The increments of RRS intensity are greatly different in which DNA enhances greatly and RNA enhances lightly. In this work, the optimum condi- tions of the interaction and some influencing factors have been investigated. The reaction mechanism and a binding model for the interaction of BLMA5 with the nucleic acids are discussed. In addition, a highly sensitive, simple and rapid new method for the determination of DNA has been developed. The detection limits (3σ) are 5.7 ng/mL for ctDNA, 7.4 ng/mL for sDNA and 9.2 ng/mL for hsDNA, respectively. The method can be applied to determination of trace amounts of DNA.     

Using Nuclear Magnetic Resonance and MS/MS Spectroscopy for the Identification of Brodimoprim Metabolites in Rat Urine

Brodimoprim,a trimethoprim analogue diaminopyrimidine, 2,4-diamino-5-(4'-bromo-3',5'-dimethoxybenzyl) pyrimidine, is a new inhibitor of bacterial dihydro folate reductases (OHFRs), it shows activity against a broad spectrum of Gram-positive and negative-bacteria. Recently we reported the results of the study on the metabolites of brodimoprim in vivo with SPE-NMR method (solid phase extraction coupled with nuclear magnetic resonance), five metabolites were detected in rat urine1. They were …     

Studies on Hepatocyte-Targeting Magnetic Resonance Imaging Macromolecular Contrast Media

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Paradigms and Paradoxes Are Acyl Azides Resonance Stabilized?

By means of the generic isodesmic reaction C₆H₅COX + RCH₃ C₆H₅COCH₃ + RX, the phenyl/vinyl thermochemical equivalence, and an experimental determination of the enthalpy of the Curtius rearrangement of acryloyl azide, the resonance energy of acyl azides was ascertained to be ca. 29 kJ mol^–1.     

Resonance raman evidence for μ-oxo linkage in ferriporphyrins

The UV-Visible absorption and resonance Raman spectra of the μ-oxo iron(III) deuteroporphyrin dimethyl ester has been studied and compared to the data obtained from the well known μ-oxo iron(III) tetraphenylporphyrin. The symmetric Fe-O-Fe stretching vibration is tentatively assigned to the 414 cm-1 line; but in contrast with the tetraphenylporphyrin dimer, no resonance enhancement is observed with excitation in the α,β region. The influence of the Fe-O-Fe angle on a charge transfer transition involving the μ-oxo linkage in the visible region is discussed.     

Theoretical Study of the Scattering Resonance State, Reaction Mechanism and Partial Potential Energy Surface of the F＋CH4→HF ＋CH3 Reaction

Many reactions with fluorine atoms have the important applications in the areas of theatmosphere and the chemical lasers, such as the reaction of fluorine atoms with methane. F( 2 P) CH 4 (X1A1)→HF(X1 Σ ) CH 3 (X 2 A′′2) ?H0300k=-32.3 kcal mol ?1 It…     

Conformational Analysis of γ-Butyrolactones by Nuclear Magnetic Resonance Spectroscopy

Conformationalanalysis[']offive-memberedringsystCms,[2]althoughofintereStbecauseofthewidespreadoccimnceofsuchSystemsinnatUre(incarbohydraes,steroids,alkaloids,nucleicarids,andcertainaminoacids),hasprogressedmuchmoreslowythanthecorresPondinganatysisofthesix-memberedhomologs,l56l:,2M=7ve27X::conformationalmobilityoffive-memberedri.gS.I$Itiscommonlyknownthatafive-memberedringekistSinanonplanarconformationanditSmoststablepuckeredformsaretheenveloPeandhalf-Chairconformations.I41TheenveloPecon…     

H-Nuclear Magnetic Resonance and Phase Solubility Studies of the Stoichiometries in 2,4-D: α- and β-Cyclodextrins Inclusion Complexes

The interaction in solution between2,4-dichlorophenoxyacetic acid with - and-cyclodextrins was evaluated by phasesolubility studies. Association constants werecalculated by this technique. The stoichiometries were1 : 2 and 1 : 1 for the - and -cyclodextrincomplexes, respectively. In order to corroborate thecomplexation and the knowledge of structural aspectsof the host : guest interaction, proton nuclearmagnetic resonance (¹H-NMR) spectroscopy wasemployed. The application of the continuous variationtechnique corroborated the calculated complexstoichiometries by solubility assays. ComplementaryNOE studies were applied in order to corroborate theproposed complex structures.