This study evaluates changes in metabolite levels in hepatocellular carcinoma (HCC) cases vs. patients with liver cirrhosis by analysis of human blood plasma using gas chromatography coupled with mass spectrometry (GC-MS). Untargeted metabolomic analysis of plasma samples from participants recruited in Egypt was performed using two GC-MS platforms: a GC coupled to single quadruple mass spectrom...

An important role of the clinical toxicology laboratory is to provide continuous diagnostic testing for patients with altered mental status and for other medical indications. To meet these needs, we have developed a new Gas Chromatography-Mass Spectrometry (GC-MS) platform that facilitates routine screening and automated reporting of 212 drugs by laboratory technologists around the clock withou...

Solitary pulmonary nodule (SPN or coin lesion) is a mass in the lung and can be commonly found in chest X-rays or computerized tomography (CT) scans. However, despite the advancement of imaging technologies, it is still difficult to distinguish malignant cancer from benign SPNs. Here we investigated the metabolic profiling of patients with benign and malignant pulmonary nodules. A combination o...

A screening procedure was developed for the simultaneous detection of mephedrone, six amphetamine-type stimulants (ATS), ketamine and its two metabolites with electrospray ionization flow injection analysis tandem mass spectrometry (FIA-MS-MS). Urine samples were fortified with deuterated analogues as internal standards, extracted with ethyl acetate and analyzed with FIA-MS-MS. The mass analyze...

the effects of different factors on growth and bio-oxidation efficiency of a native strain of acidithiobacillus ferrooxidans have been evaluated by the utilization of response surface methodology, rsm. medium ph and iron concentration were found to be the most significant factors while temperature and ammonia concentrations had the least weight within the ranges investigated. optimum operationa...

A method for the determination of creatinine in human serum by isotope dilution-mass spectrometry is described. The analytical procedure comprises the following steps: Addition of [13C,15N2 )creatinine to the serum sample; ion exchange chromatography on the cation exchange resin AG 50W-X2; formation of the trimethylsilyl derivative; gas liquid chromatography-mass spectrometry (GC-MS); selected ...

Compound-specific isotope analysis (CSIA) by isotope ratio mass spectrometry (IRMS) following on-line combustion (C) of compounds separated by gas chromatography (GC) is a relatively young analytical method. Due to its ability to measure isotope distribution at natural abundance level with great accuracy and high precision, GC-C-IRMS has increasingly become the method of choice in authenticity ...

Ceratitis fasciventris, Ceratitis anonae and Ceratitis rosa are polyphagous agricultural pests originating from the African continent. The taxonomy of this group (the so-called Ceratitis FAR complex) is unclear. To clarify the taxonomic relationships, male and female-produced volatiles presumably involved in pre-mating communication were studied using comprehensive two-dimensional gas chromatog...

A specific gas chromatographic (GC) detection method for edible bird's nest (EBN) based on identifying the composition of the oligosaccharide chain combined with glycoprotein in EBN is developed. Five monoses (D-mannitose, D-galactose, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, and N-acetyl neuraminate) that constitute the oligosaccharide chain are detected using GC and GC-mass spectrome...

Our understanding of formation processes, physical properties, and climate/health effects of organic aerosols is still limited in part due to limited knowledge of organic aerosol composition. We present speciated measurements of organic aerosol composition by two methods: in situ thermaldesorption proton-transfer-reaction mass spectrometry (TDPTR-MS) and offline two-dimensional gas chromatograp...