The fate of chlordane and other persistent organic pollutants in the environment is of international concern. The behavior of persistent organic pollutants under both abiotic and biotic conditions must be determined for the comprehensive elucidation of their cycling through the biosphere. Standard analytical methods such as gas chromatography with electron capture detection are adequate for stu...

We present a candidate reference method for the determination of serum theophylline by isotope dilution gas chromatography-mass spectrometry, using extractive alkylation in sample preparation. The maximum method bias was < 1.0%. The mean method imprecision (CV) was 0.63% (range 0.37-0.96%), calculated from the results of six measurements independently performed on 3 days. The maximum total erro...

The present study employs a recently reported liquid chromatography-(time of flight) mass spectrometry procedure for the simultaneous analysis of 22 benzodiazepines in human urine specimens. The analysis focused on the most commonly prescribed benzodiazepines and/or their metabolites. Using this method, the limit of quantitation for the benzodiazepines tested ranged from 2 to 10 ng/mL, while th...

A procedure for the determination of oxycodone in meconium using direct ELISA microplate technology followed by electron impact gas chromatography-mass spectrometry (GC-MS) is described for the first time. The abuse of oxycodone (OxyContin) has been widely discussed in mainstream media, and it has been described as a cheap form of heroin. Oxycodone has been reported as having a high degree of a...

A study on the rapid identification of phthalates in polymer materials has been conducted by employing gas chromatography-mass spectrometry coupled with a pyrolyzer (Py-GC/MS). Since Py-GC/MS does not require any complex solvent-extraction process, a rapid screening of phthalates should be possible. In this study, polymer samples were directly introduced into the pyrolyzer in order to thermally...

The characterization of ink on paper is of importance for dating and comparing questioned ink entries in forensic document examination. Inks are commonly characterized by their colorant profile that is identified by well-established analytical methods. Numerous ink formulations show identical colorant profiles, though. In order to differentiate inks that are not distinguishable by colorant anal...

Quantitative analyses of abscisic acid in the elongating zone of a single maize root (Zea mays L. cv LG 11) were performed by gas chromatography-mass spectrometry using negative chemical ion ionization. Data showed that the more abscisic acid, the slower the growth, but a large dispersion of individual values was observed. We assume that abscisic acid is perhaps not correlated only to the growt...

A method for determination of imidacloprid in water and soil samples, previous hydrolysis in basic medium, followed by gas chromatography-mass spectrometry and selected ion monitoring. A 250-ml sample water was previously heated in basic medium to give a hydrolysis compound of adequate volatility. The hydrolysis product which was extracted and isolated with chlorotorm was identified and found t...

Lipids typically exist in a state in which various fatty acids are bound to a backbone such as glycerol, sphingosine, cholesterol, etc. With recent advances in analytical techniques, especially those associated with mass spectrometry, identification of lipid components, including their molecular species, is becoming possible. However, it is still difficult to identify all the components of lipi...

Cultures of Pseudomonas putida growing in solutions with diphenylmethane as sole carbon source formed 1,1,1',1'-tetraphenyldimethyl ether. The product was identified by gas chromatography, mass spectrometry, and infrared and nuclear magnetic resonance spectrometry. The formation of benzophenone, benzhydrol, and phenylglycolic acid was established by gas chromatography and mass spectrometry. Sim...