The technology presents a number of environmental challenges as the wells are drilled vertically through aquifers on their way to the deep shale deposits thousands of feet under the surface, and then turned horizontally and drilled another several thousand feet through the shale deposit. Herein lies the challenge: in the process of drilling the wells and preparing them for production (including...

This article describes gas chromatography-flame ionization detection method for determination of 17 β-estradiol in rabbit plasma. 17 β-estradiol and internal standard progesterone were extracted from plasma using liquid-liquid extraction method. Linearity was found between 0.25 and 20 μg/ml (r(2)=0.994) for plasma samples. Intra-day and inter-day precision, expressed as the relative standard de...

A simple and rapid method for determination of mexiletine in pharmaceutical preparations was developed and validated using gas chromatography with flame ionization detection (GC-FID). GC separation was performed in about 5 min using a HP-5 capilary column (30 m x 0.320 mm, 0.25μm). Nitrogen was used as carrier gas at a flow-rate of 2 mL min. After injection of the sample at inlet temperature 25...

Felbamate, a newly developed antiepileptic agent, has been demonstrated to control partial and generalized seizures effectively. We have developed a gas-chromatographic method for the determination of felbamate, using a wide-bore capillary column, a flame ionization detector, and a simple extraction procedure. The assay day-to-day precision (n = 20) was 5.2% and 3.6% for drug concentrations of ...

Volatiles are frequently abused as inhalants. The methods used for identification are generally nonspecific if analyzed concurrently with ethanol or require an additional analytical procedure that employs mass spectrometry. A previously published technique utilizing a capillary flow technology splitter to simultaneously quantitate and confirm ethyl alcohol by flame ionization and mass spectrome...

The determination of residual solvents in pharmaceuticals is one of the most important gas chromatography (GC) applications in quality assurance/quality control (QA/QC) in the pharmaceutical industry. Sample introduction is normally done using static headspace (SHS). In routine QC, GC with flame ionization detection (FID) is preferred, while mass spectrometry (MS) can be used for screening and ...

A new method for the determination of linoleic acid (LA) in toothpaste by a routine analysis has been proposed. Studies were based on the ISO 5509 procedure, which was modified for the purpose of LA determination in the toothpaste. Gas chromatography (GC) was employed for the qualitative and quantitative determination of linoleic acid methyl ester. The content of LA (5.31%) in sunflower oil add...

Current research of complex chemical systems, including biomass pyrolysis, petroleum refining, and wastewater remediation requires analysis of large analyte mixtures (>100 compounds). Quantification of each carbon-containing analyte by existing methods (flame ionization detection) requires extensive identification and calibration. In this work, we describe an integrated microreactor system call...

We introduce a new in-situ instrument, Thermal desorption Aerosol GC/MS-FID (TAG), capable of hourly measurements of speciated organic compounds in atmospheric aerosols. Aerosol samples are collected into a thermal desorption cell by means of humidification and inertial impaction. The sample is thermally desorbed and transferred with helium carrier gas into a gas chromatography (GC) column, wit...