CE provides evidence of the stereoselective hydroxylation of norketamine in equines.

CE with multiple isomer sulfated-CD as selector was used for the simultaneous analysis of the stereoisomers of ketamine, norketamine, 5,6-dehydronorketamine and hydroxylated metabolites of norketamine in liquid/liquid extracts of (i) in vitro incubations with ketamine or norketamine and equine liver microsomes and (ii) plasma and urine of ponies receiving a target-controlled infusion of ketamine under isoflurane anesthesia. Hydroxynorketamine metabolites with the hydroxy group at the cyclohexanone ring could be shown to be formed stereoselectively both in vitro and in vivo. Due to the lack of standard compounds, urinary extracts were fractionated by HPLC followed by characterization of the collected fractions with CE and LC-MS(n) with 0.

Kinetic study of neuropeptide Y (NPY) proteolysis in blood and identification of NPY3-35: a new peptide generated by plasma kallikrein.

There is little information on how neuropeptide Y (NPY) proteolysis by peptidases occurs in serum, in part because reliable techniques are lacking to distinguish different NPY immunoreactive forms and also because the factors affecting the expression of these enzymes have been poorly studied. In the present study, LC-MS/MS was used to identify and quantify NPY fragments resulting from peptidolytic cleavage of NPY(1-36) upon incubation with human serum. Kinetic studies indicated that NPY(1-36) is rapidly cleaved in serum into 3 main fragments with the following order of efficacy: NPY(3-36) >> NPY(3-35) > NPY(2-36).

Characterisation of the peptaibiome of the biocontrol fungus Trichoderma atroviride by liquid chromatography/tandem mass spectrometry.

The present study describes the liquid chromatography/tandem mass spectrometry (LC/MS/MS)-based screening and characterisation of linear antibiotic alpha-aminoisobutyric acid (Aib)-containing non-ribosomal peptides (NRP) in culture samples of the filamentous fungus Trichoderma atroviride ATCC 74058. Fungal culture filtrates were enriched by solid-phase extraction (SPE) and separated by reversed-phase high-performance liquid chromatography (HPLC), prior to mass spectrometric (MS) and tandem mass spectrometric (MS/MS) analysis on a triple quadrupole-linear ion trap tandem mass spectrometer. A workflow consisting of two alternative screening strategies was applied to search for NRP.

Enantioselective analysis of ketamine and its metabolites in equine plasma and urine by CE with multiple isomer sulfated beta-CD.

CE with multiple isomer sulfated beta-CD as the chiral selector was assessed for the simultaneous analysis of the enantiomers of ketamine and metabolites in extracts of equine plasma and urine. Different lots of the commercial chiral selector provided significant changes in enantiomeric ketamine separability, a fact that can be related to the manufacturing variability. A mixture of two lots was found to provide high-resolution separations and interference-free detection of the enantiomers of ketamine, norketamine, dehydronorketamine, and an incompletely identified hydroxylated metabolite of norketamine in liquid/liquid extracts of the two body fluids.

Coordination chemistry of dinucleating P2N2S ligands: preparation and characterization of cationic palladium complexes.

The thioethers (4-tert-butyl-2,6-bis((2-(diphenylphosphino)ethylimino)methyl)phenyl)(tert-butyl)sulfane (tBuL3) and (4-tert-butyl-2,6-bis((2-(diphenylphosphino)ethylamino)methyl)phenyl)(tert-butyl)sulfane (tBuL4) react readily with [Pd(NCMe)2Cl2] to give the dinuclear palladium thiophenolate complexes [(L3)Pd2(Cl)2]+ and [(L4)Pd2(micro-Cl)]2+ (HL3=2,6-bis((2-(diphenylphosphino)ethylimino)methyl)-4-tert-butylbenzenethiol, HL4=2,6-bis((2-(diphenylphosphino)ethylamino)methyl)-4-tert-butylbenzenethiol). The chlorides in could be replaced by neutral (MeCN) and anionic ligands (NCS-, N3-, I-, CN-) to give the dinuclear PdII complexes [(L3)Pd2(NCMe)2]3+, [(L3)Pd2(SCN)2]+, [(L3)Pd2(N3)2]+, [(L3)Pd2(I)2]+, and [(L3)Pd2(CN)2]+. The acetonitrile ligands in are readily hydrated to give the corresponding amidato complex [(L3)Pd2(NHCOMe)]2+.

Large size anion binding with iron(II) complexes of a 5,5'-disubstituted-2,2'-bipyridine ligand.

Three 5,5'-substituted 2,2'-bipyridyl ligands around a metal atom form two clefts which can encapsulate sulfate, perchlorate, or nitrate anions.