The first analytical intercomparison of fingerprint residue using equivalent samples of latent fingerprint residue and characterized by a suite of relevant techniques is presented. This work has never been undertaken, presumably due to the perishable nature of fingerprint residue, the lack of fingerprint standards, and the intradonor variability, which impacts sample reproducibility. For the fi...

Disopyramide is determined in serum by gas chromatography with a nitrogen-selective detector, by liquid chromatography, and by gas chromatography--mass spectrometry. Comparable results are obtained with the three techniques, with a within-run and between-run precision of 5 to 10% (coefficient of variation). Least-squares analysis of data on patients' sera, analyzed first by gas chromatography (...

Despite the unprecedented popularity of separation chromatography, the measurement of coeluting isomeric chemicals remains an extremely difficult task. We developed an analytical scheme capable of measuring two coeluting isomers using a single chromatographic column and a gas chromatography/tandem mass spectrometry system. The protocol utilized two product ion fragments generated from a common ...

Mass spectrometry and ion chemistry of alkylbenzenes, today, is much more than the gas-phase reactions of their radical cations and their prominent fragment ions, such as C7H7+ and C7Hs+'. Indeed, the gas-phase chemistry of gaseous ions originating mainly from the electron impact (EI) ionization of alkylbenzenes has been investigated extensively for more than 35 years and has revealed to us num...

An unknown guanidino-positive peak has been identified in urines of three sisters affected with hyperargininaemia. Identification was made on the basis of its similarity with the liquid and thin-layer chromatographic characteristics of enzymatically synthesized 2-oxo-5-guanidinovaleric acid. Identification was also made by combined gas chromatography-mass spectrometry of the unknown compound pe...

Sample Types LC/MS systems facilitate the analysis of samples that traditionally have been difficult to analyze. Despite the power and usefulness of gas chromatography/mass spectrometry (GC/MS), many compounds are impossible to analyze with GC/MS. LC/MS significantly expands the effective analytical use of mass spectrometry to a much larger number of organic compounds. Gas chromatography and GC...

cis-8,11,14,17-[1-14C]Eicosatetraenoic acid was incubated with microsomes of ram seminal vesicles and 1 mM glutathione for 3 min at 37 degrees C. The main metabolite was identified as 17,18-dehydroprostaglandin E1 by capillary column gas chromatography-mass spectrometry. Human seminal fluid was analyzed for the presence of 17,18-dehydroprostaglandin E1 and prostaglandin E3. Whereas prostaglandi...

Gas chromatography (GC), gas chromatography±mass spectrometry (GC±MS) and gas chromatography±mass spectrometry±mass spectrometry (GC±MS±MS) with co-injected synthetic standards were used to analyse the biomarker patterns of some Tertiary lacustrine clayey dolomites from the Biyang Basin, China. The lithology, low Pr/Ph ratio and high gammacerane content of these sediments indicated that high sa...

the essential oil of peucedanum ru t h e n i c u m fruits, obtained by hydrodistillation, was analyzed by gas chromatography and gas chromatography mass spectrometry. among the 31 identified constituents accounting for 83.9% of the total oil, the major components were 1,8-cineole (11.15%), camphor (5.86%), z-carveol (6.88%), l-carvone (5.61%), 8,9-dehydroisolongifolene (11.35%), caryophyllene o...