Laboratory of Molecular Spectroscopy, Institute of Chemistry, Eötvös University, PO Box 32, H-1518, Budapest 112, Hungary.
Published: May 2012
AI Article Synopsis
Article Abstract
Former assignments of the matrix-isolation infrared (MI-IR) spectrum of 2-chloropropionic acid are revised with the help of near-infrared (NIR) laser irradiation induced change in conformer ratios. This method allows not only the unambiguous assignment of each band in the MI-IR spectrum to the two trans (Z) and the cis (E) conformers but also the assignment of the spectral bands to different matrix sites. The tunneling decay of the higher-energy cis conformer prepared from both trans conformers in different sites is also investigated. It is shown that the tunneling decay time is very sensitive to the matrix site, especially if the in situ prepared high-energy conformer has a strained geometry in the matrix cage. The analysis shows that the kinetics of some cis → trans back conversion processes cannot be fitted by a single exponential decay. The possible reasons of this observation are examined and discussed. The present and former results clearly show that, in addition to tunneling processes, the decay rates strongly depend on solid-state effects. Therefore, simple theoretical predictions of decay rates, which do not take into account the solid-state effects, can only be compared to experimental observations only if experimentally proven that these effects do not significantly affect the experimentally measured tunneling rates.
Institutes of Physical Science and Information Technology, Centre for Atomic Engineering of Advanced Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Department of Chemistry, Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University Hefei Anhui 230601 China
Metal nanoclusters are excellent electrochemiluminescent luminophores owing to their rich electrochemical and optical properties. However, the optical activity of their electrochemiluminescence (ECL) is unknown. Herein, we achieved, for the first time, the integration of optical activity and ECL, , circularly polarized electrochemiluminescence (CPECL), in a pair of chiral AuAg metal nanocluster enantiomers.
Rationale: The analytical detection of chemical residues from sodium monofluoroacetate (MFA) ingestion in targeted predatory wildlife and in pesticide misuse incidents perpetrated against nuisance companion animals remains a concern in veterinary forensic toxicology. There is a current need for chemically stable sample extracts with reliable and specific diagnostic methods for trace quantities in diverse diagnostic matrices.
Methods: Biphasic pentafluorobenzylation provided a simple combined extraction and derivatization procedure for removing MFA in a chemically stable form from a complex matrix such as stomach contents.
This study aimed to develop a novel and practical fluorescent method for GSH detection in complex biological samples. To this end, a series of coumarin-based fluorescent probes was designed and synthesized using various aliphatic halogens as the sensing group. By using a new evaluation method of GSH/Cys/Hcy coexisting conditions, the probe with chloropropionate (CBF3) showed a high selectivity, excellent sensitivity, good stability for GSH detection.
Precisely regulating the ligand exchange on the nanocluster (NC) surface is challenging but important for fully understanding metal-ligand interactions and transformations. In this work, the homosilver nanocluster Ag(TBBM)(CHCOO) (Ag) and its Au-substitution derivative AuAg(TBBM)(CHCOO) (AuAg) have been synthesized and characterized by single-crystal X-ray crystallography (SC-XRD), nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). By precisely controlling the template metal exchange progress, the intermediate product, namely, AuAg(TBBM)(CHCOO) (AuAg-inter), was also obtained and then characterized by SC-XRD.
Dehalogenases continue to garner interest of the scientific community due to their potential applications in bioremediation of halogen-contaminated environment and in synthesis of various industrially relevant products. Example of such enzymes is DehL, an L-2-haloacid dehalogenase (EC 3.8.
