Browsing CHEM Faculty Scholarship by Title
Now showing items 244-263 of 496
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Investigations of acidity and nucleophilicity of diphenyldithiophosphinate ligands using theory and gas-phase dissociation reactions
(American Chemical Society, 2008-04-21)Diphenyldithiophosphinate (DTP) ligands modified with electron-withdrawing trifluoromethyl (TFM) substitutents are of high interest because they have demonstrated potential for exceptional separation of Am (3+) from ... -
Ion mobility separation of peptide isotopomers
(Springer International Publishing AG, 2016-05)Differential or field asymmetric waveform ion mobility spectrometry (FAIMS) operating at high electric fields fully resolves isotopic isomers for a peptide with labeled residues. The naturally present isotopes, alone and ... -
Ion mobility spectrometry of macromolecules with dipole alignment switchable by varying the gas pressure
(American Chemical Society, 2019-06-05)Since inception in the 1980s, differential or field asymmetric waveform ion mobility spectrometry (FAIMS) was implemented at or near the ambient gas pressure (AP). Recently, we developed FAIMS at 15-30 Torr within a mass ... -
Ion mobility spectrometry of superheated macromolecules at electric fields up to 500 Td
(American Chemical Society, 2021-08-23)Since its inception in 1980s, differential or field asymmetric waveform ion mobility spectrometry (FAIMS) has been implemented at or near ambient gas pressure. We recently developed FAIMS at 15–30 Torr with mass spectrometry ... -
Ionic inhibitors of human leukocyte elastase: pyridinium and phenyl carboxylate derivatives of 3-alkyl-N-hydroxysuccinimide
(John Wiley and Sons, 1990-10-01)A series of pyridinium and phenyl carboxylate derivatives of 3-alkyl-N-hydroxysuccinimide has been synthesized; the compounds have been shown to be highly effective, time-dependent inactivators of human leukocyte elastase. ... -
IRMPD and DFT study of the loss of water from protonated 2-hydroxynicotinic acid
(Elsevier, 2012-07-06)Collision-induced dissociation (CID) of protonated 2-hydroxynicotinic acid (2-OHNic) generates a dominant product ion through loss of 18 mass units, presumably the elimination of water. Subsequent isolation and storage of ... -
IRMPD spectroscopy b2 ions from protonated tripeptides with 4-aminomethyl benzoic acid residues
(Elsevier, 2012-02)Collision-induced dissociation (CID) of the peptide alanine-4-aminomethylbenzoic acid-glycine, A(AMBz)G generates a prominent b2 ion despite a previous report [E.R. Talaty, T.J. Cooper, S.M. Osburn, M.J. Van Stipdonk, ... -
IRMPD spectroscopy of anionic group II metal nitrate cluster ions
(Springer, 2009-05-01)Anionic group II metal nitrate clusters of the formula [M(2)(NO(3))(5)](-), where M(2) = Mg(2), MgCa, Ca(2), and Sr(2), are investigated by infrared multiple photon dissociation (IRMPD) spectroscopy to obtain vibrational ... -
Iron and cobalt complexes of 2,6-Diacetylpyridine-bis(R-thiosemicarbazone) (R=H, phenyl) showing unprecedented ligand deviation from planarity
(Elsevier, 2009-03-02)The syntheses, characterization, and single-crystal X-ray crystal structures are reported for four complexes of iron and cobalt with the pentadentate ligands, 2,6-diacetylpyridinebis(thiosemicarbazone) (H(2)L(1)) and ... -
Isotope labeling and theoretical study of the formation of a3* ions from protonated tetraglycine
(Springer, 2006-12-01)Extensive 13C, 15N, and 2H labeling of tetraglycine was used to investigate the b3+ --> a3* reaction during low-energy collision-induced dissociation (CID) in a quadrupole ion-trap mass spectrometer. The patterns observed ... -
Kinetic evidence for channeling of dopamine between monoamine transporter and membranous dopamine-beta-monooxygenase in chromaffin granule ghosts
(American Society for Biochemistry and Molecular Biology, 2004-04-09)The nature of coupling between the uptake and dopamine-beta-monooxygenase (DbetaM) catalyzed hydroxylation of dopamine (DA) was studied in bovine chromaffin granule ghosts. Initial rate and transient kinetics of DA uptake ... -
LacI-DNA-IPTG Loops: Equilibria among conformations by single-molecule FRET
(American Chemical Society, 2013-02-13)The E. coli Lac repressor (LacI) tetramer binds simultaneously to a promoter-proximal DNA binding site (operator) and an auxiliary operator, resulting in a DNA loop, which increases repression efficiency. Induction of the ... -
Latent isocynate derivatives useful for deactivating enzymes
(United States Patent and Trademark Office, 1990-05-29)Certain amino-acid derivatives are disclosed as effective inhibitors of human leukocyte elastase and therefore useful in preventing the imbalance of this proteolytic enzyme in vivo. The compounds specifically are derivatives ... -
Linear and differential ion mobility separations of middle-down proteoforms
(American Chemical Society, 2018)Comprehensive characterization of proteomes comprising the same proteins with distinct post-translational modifications (PTMs) is a staggering challenge. Many such proteoforms are isomers (localization variants) that require ... -
A linear S-bridged trinuclear cobalt(III) complex with 2-aminobenzenethiol: synthesis, crystal structure, and spectroscopic characterization
(Taylor & Francis, 2013-09-10)Treatment of cobalt(II) perchlorate hexahydrate with 2 M equiv. of 2-aminobenzenethiol (Habt) in acetonitrile afforded a tricationic tricobalt complex, [Co{Co(abt)3}2](ClO4)3·2CH3CN, by aerial oxidation. The molecular ... -
Lipophilic cationic cyanines are potent complex I inhibitors and specific in vitro dopaminergic toxins with mechanistic similarities to both rotenone and MPP+
(American Chemical Society, 2016-08-10)We have recently reported that simple lipophilic cationic cyanines are specific and potent dopaminergic toxins with a mechanism of toxicity similar to that of the Parkinsonian toxin MPP+. In the present study, a group of ... -
Loading and release of doxorubicin with magnetic nanotubes
(John Wiley & Sons, Inc., 2015-03)In this work, we study magnetic nanotubes (MNTs) as drug carriers to control the loading and release of doxorubicin (Dox). The inner surfaces of MNTs where Dox molecules are stored are modified with C18-silane and ... -
Localization of post-translational modifications in peptide mixtures via high-resolution differential ion mobility separations followed by electron transfer dissociation
(Springer International Publishing, 2016-12)Precise localization of post-translational modifications (PTMs) on proteins and peptides is an outstanding challenge in proteomics. While electron transfer dissociation (ETD) has dramatically advanced PTM analyses, mixtures ... -
Long-range stabilization of anthrax protective antigen upon binding to CMG2
(American Chemical Society, 2014-09-30)Protective antigen (PA) mediates entry of edema factor (EF) and lethal factor (LF) into the cytoplasmic space of the cells through the formation of a membrane-spanning pore. To do this, PA must initially bind to a host ...