Search PubMed⌕ Search

PubMed · 12868751

An extremely stable, self-complementary hydrogen-bonded duplex.

Abstract

This paper describes the design, synthesis and characterization of a self-complementary six-H-bonded duplex with an association constant greater than 10(9) M(-1) in CHCl3.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Huaqiang Zeng, Xiaowu Yang, Amy L Brown, Suzana Martinovic, Richard D Smith, Bing Gong. 2003-07-07. An extremely stable, self-complementary hydrogen-bonded duplex.. https://doi.org/10.1039/b301791e

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

An ultra acid stable reversed stationary phase.

We report a new reversed phase liquid chromatography (RPLC) phase with remarkable acid stability using dimethyl(ethylphenylchloromethyl)chlorosilane (1), oligomeric polystyrene (PS), and octylbenzene (C8). This phase Si-1-PS-C8 was prepared using silica modification processes and Friedel-Crafts alkylation chemistry. Under highly aggressive mobile phase conditions, Si-1-PS-C8 exhibited remarkable stability as evinced by only minimal reduction in retention factor (k') after 1400 column volumes at pH = 0.5 and 150 degrees C. The peak shapes for a variety of basic solutes were symmetric using Si-1-PS-C8. Evidence for a highly cross-linked coating of the silica particles was observed using scanning electron microscopy. The remarkable stability of this phase is unparalleled as compared to all other RPLC phases reported to date.

Drug Stability↗

Effect of high pressure and reversed micelles on the fluorescent proteins.

Two physico-chemical perturbations were applied to ECFP, EGFP, EYFP and DsRed fluorescent proteins: high hydrostatic pressure and encapsulation in reversed micelles. The observed fluorescence changes were described by two-state model and quantified by thermodynamic formalism. ECFP, EYFP and DsRed exhibited similar reaction volumes under pressure. The changes of the chemical potentials of the chromophore in bis(2-ethylhexyl)sulfosuccinate (AOT) micelles caused apparent chromophore protonation changes resulting in a fluorescence decrease of ECFP and EYFP. In contrast to the remarkable stability of DsRed, the highest sensitivity of EYFP fluorescence under pressure and in micelles is attributed to its chromophore structure.

Drug Stability↗

Model studies on the stability of folic acid and 5-methyltetrahydrofolic acid degradation during thermal treatment in combination with high hydrostatic pressure.

Stability of folic acid and 5-methyltetrahydrofolic acid in phosphate buffer (0.2 M; pH 7) toward thermal (above 65 degrees C) and combined high pressure (up to 800 MPa)/thermal (20 up to 65 degrees C) treatments was studied on a kinetic basis. Residual folate concentration after thermal and high pressure/thermal treatments was measured using reverse phase liquid chromatography. The degradation of both folates followed first-order reaction kinetics. At ambient pressure, the estimated Arrhenius activation energy (E(a)) values of folic acid and 5-methyltetrahydrofolic acid thermal degradation were 51.66 and 79.98 kJ mol(-1), respectively. It was noticed that the stability of folic acid toward thermal and combined high pressure thermal treatments was much higher than 5-methyltetrahydrofolic acid. High-pressure treatments at room temperature or higher (up to 60 degrees C) had no or little effect on folic acid. In the whole P/T area studied, the rate constant of 5-methyltetrahydrofolic acid degradation was enhanced by increasing pressure, and a remarkable synergistic effect of pressure and temperature on 5-methyltetrahydrofolic acid degradation occurred at temperatures above 40 degrees C. A model to describe the combined pressure and temperature effect on the 5-methyltetrahydrofolic acid degradation rate constant is presented.

Drug Stability↗