Fused silica capillary column GC/MS for the analysis of priority pollutants

Operational characteristics have been determined for fused silica capillary column (FSCC) GC/MS as applied to “extractable” priority polutants. Chromatographic data show excellent relative retention time (RRT) intralaboratory precision and interlaboratory accuracy when multiple internal standards are empolyed. Potential chromatographic problems, such as column overload and “double peaking”, are addressed. Response factor relative standard deviations (RSD) at 50 ng for most of the extractable priority pollutants over the long term indicated precise determination (i.e. RSD generally ≤ 10%). Linearity was demonstrated over two orders of magnitude for FSCC GC/MS analysis of compounds with relatively low and high RF (response factor) values. Potential quantitative problems, such as saturation, are discussed. For certain aromatic priority pollutants interlaboratory RF agreement was observed. This was noted as perhaps the most important property of FSCC GC/MS analysis when the multiple internal standard approach is utilized. Determinations of extractable priority pollutants are directly compared for paced column GC/MS and FSCC GC/MS analysis of separate and composited extracts. For six extracts analyzed in triplicate, the latter configuration was shown to produce more consistent results. In view of the superior analysis logistics of composite extract FSCC GC/MS analysis, this approach was established as the preferred method for the analysis of priority pollutants classified as extractable.     

Direct determination of the phenanthrene and methylphenanthrene isomer distribution in crude oils by multidimensional capillary GC

The methylphenanthrene index (MPI) [1,2] which was recognized as suitable for the assessment of the “thermal” history of sedimentary organic matter, can be determined directly i.e. without preceding LC group separations by application of multi-dimensional GC in capillary columns. A GC double oven instrument (Siemens Sichromat 2) equipped with a “live switching” coupling piece was used for the necessary measurements.     

Determination of Broxaterol in Plasma by Coupled HPLC-GC

For the analysis of broxaterol 1-(3-bromoisoxazol-5-yl)-2-(tert-butylamino)ethanol in human plasma and urine an on-line HPLC-GC apparatus was used applying the “concurrent solvent evaporation” technique described in previous studies. Broxaterol is quantitatively determined by capillary GC with ECD detection, after extraction from plasma and derivatization. The detection limit of 0.03 ng/ml permits pharmacokinetic studies in man after oral and intravenous administration of the drug.     

Distorted solvent peaks in capillary GC: A symptom of porous column surfaces

Many uncoated precolumns, and to a lesser extent separation columns, strongly retain some of the solvent. Retarded release of such solvent elevates the baseline after the solvent peak and causes ugly “humps” of eluted solvent as the temperature is increased. The problem is probably a result of retention by a porous surface, e.g. surfaces obtained by leaching or hydrothermal treatment of capillaries prior to silylation. It is assumed that other problems with capillary columns can be explained by the same mechanism, including: a kind of adsorption including apolar compounds, and “ghost” peaks as well as “memory” effects. Fused silica capillaries are superior to glass, but even for these special procedures are required in order to achieve thorough deactivation of the internal surface without introducing porosity.     

Characterization of fatty oils by pattern recognition of triglycerides profiles

The triglyceride profiles for corn, soybean, sunflower, grapestone, olive and olive husks oils were obtained by high temperature capillary gas chromatography on HT-FS capillary columns coated with OV-17-OH. The data were treated by methods of computerized pattern analysis, involving principal component analysis, discriminant analysis, and hierarchical clustering. A graphical representation of results as “star symbol plots” allows prompt visual recognition of the characteristic profiles and straightforward qualitative identification of unknowns as well as recognition of adulterations.     

ChemInform Abstract: Reactions of Sodium Clusters with Oxygen Molecules.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: H-Bridged Structures for Tetrahedranes A4H4 (A: C,Si, Ge,Sn, and Pb).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Neutron Diffraction of Homopolyatomic Bismuth Ions in Liquid Bi5(AlCl4)3 and ab initio Study of the Structure and Bonding of the Isolated Bi53+ Ion.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Anharmonic Force Fields of Arsine,Stibine, and Bismutine

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Studies on the Electronic Structure of MCl4 (M: Ti,Zr, Hf) Type Molecules by the MS-Xα Method.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Quantitative Analysis of Electron Correlation in M2Po (M: Cu,Ag, Au) Systems

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Use of Threshold Electron and Fluorescence Coincidence Techniques to Probe the Decay Dynamics of the Valence States of CF+ 4, SiF+ 4, SiCl+ 4, and GeCl+ 4.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Electronic Structure and Energies of Interatomic Interactions in Technetium,Rhenium, Ruthenium,and Osmium Diborides.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Ab initio Study of the Molecular Structure of Oxo and Thio Salts LAB3 (L: Li and Na; A: N,P, and S+; and B: O and S).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: First‐Principles Electronic Structure Calculations of Ba5Si2N6 with Anomalous Si2N6 Dimeric Units.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Molecular Structure of C(GeBr3)4 Determined by Gas-Phase Electron Diffraction and Density Functional Theory Calculations: Implications for the Length and Stability of Ge—C Bonds in Crystalline Semiconductor Solids.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: The Electronic Structure of the YNi5, YNi4Al and YNi3Al2 Intermetallic Compounds and Their Model Monohydrides

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Bonding and Stability of the Hydrogen Storage Material Mg2NiH4

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Experimental and Theoretical Characterization of the Gas-Phase NSO- 2 Ion.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.     

ChemInform Abstract: Electronic Structure,Chemical Bonding,and Jahn-Teller Distortions in CdPS3.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.