background ziziphora tenuior l. known as kakuti in persian, is used in traditional medicine for fever, dysentery, uterus infection and as an analgesic. it is used also in the treatment of gastrointestinal disorders as carminative, or remedy of diarrhea or nausea. major components of plant essential oil including pulegone, isomenthone, thymol, menthone, and piperitone are suggested to be respons...

background valproic acid is widely used as an anticonvulsant and mood-stabilizing drug in the treatment of epilepsy. determination of serum valproic acid is required in epilepsy therapy for efficient control of seizures. objectives in the present study, the gas chromatography method was applied to determine serum valproic acid and resulting data were compared with those obtained by high perform...

an air–assisted liquid–liquid microextraction method for the extraction and preconcentration of trace amounts of some synthetic phenolic antioxidants in biological fluids followed by their determination by gas chromatography–flame ionization detection has been reported. in this method the target analytes are extracted into a few microliters of carbon tetrachloride (extraction solvent) from an a...

background: a new microextraction method named dispersive liquid-liquid microextraction (dllme) for determination of chloroform in pool water and blood of swimmers after swimming is described. methods: this method was performed based on coupling dispersive liquid-liquid microextraction (dllme) with gas chromatog­raphy-mass spectrometry (gc-ms). methanol and trichloroethylenes were used as the d...

objective(s): dispersive liquid-liquid microextraction coupled with gas chromatography (gc)-flame ionization detector was developed for the determination of valproic acid (vpa) in human plasma. materials and methods: using a syringe, a mixture of suitable extraction solvent (40 µl chloroform) and disperser (1 ml acetone) was quickly added to 10 ml of diluted plasma sample containing vpa (ph, 1.0...

the aim of this study was to investigate the removal of toluene from air through nano-graphene modified by ionic liquid (ng-il). the batch adsorption experiments in glass bottle of gas chromatography equipped with flame ionization detector (gc-fid) were used. graphene ultrahigh-quality synthesized by substrate-free gas-phase method in a single step and graphene sheets were deposited with ionic-...

this study propose a new analytical protocol for the determination of benzene, xylene, toluene and styrene in water samples using homogeneous liquid-liquid microextraction via flotation assistance (hllme-fa) technique followed by gas chromatography-mass spectrometry (gc-ms). in this research, a special extraction cell was designed to facilitate collection of the low-density solvent extraction. ...

polycyclic aromatic hydrocarbons (pahs) which are toxic pollutants are released by various sources of urban combustion. ahvaz in iran with around a million population and the industrial and oil centers, has encountered air quality problems. samples of dibenzo (a,h) antheracen were collected from six stations in ahvaz particle and gas phase in summer 2010. dibenzo(a,h) antheracen were collected ...

We describe the use of electron-capture gas chromatography or reversed-phase "high-performance" liquid chromatography for concurrent analysis for diazepam and nordiazepam in serum. In the gas-chromatographic analysis our use of a new chemically deactivated stationary liquid phase, SP 2250-DB (Supelco, Inc.), resulted in improved chromatographic sensitivity and peak symmetry for the two benzodia...