Kleinová J., Klejdus B. (2014): Determination of volatiles in beer using solid-phase microextraction in combination with gas chromatography/mass spectrometry. Czech J: Food Sci., 32: 241–248. Headspace solid phase microextraction and purge and trap analysis were used for the determination of volatiles in beer. These methods were compared with the analysis of unconcentrated gas phase and liquid ...

INTRODUCTION Microextraction processes with UV-Vis measurement have been developed and validated for analysis of bosentan in biological samples. METHODS In this work, liquid-liquid microextraction procedures (DLLME & USAEME) were employed for cleanup, pre-concentration, and determination of bosentan in biological samples by UV-Vis spectroscopy at 270 nm. The method was validated and applied t...

A fast headspace solid-phase microextraction gas chromatography method for micro-volume (0.1 mL) samples was optimized for the analysis of haloacetic acids (HAAs) in aqueous and biological samples. It includes liquid-liquid microextraction (LLME), derivatization of the acids to their methyl esters using sulfuric acid and methanol after evaporation, followed by headspace solid-phase microextract...

We report the application of the dispersive liquid-liquid microextraction coupled to hollow-fibre membrane-assisted liquid-phase microextraction and its application for extraction of atrazine and triclosan. Under optimum conditions, namely, 25 μL of a 1 : 4 chlorobenzene : ethyl acetate mixture dispersed in 1 mL of aqueous sample, 10% (m/v) NaCl, a magnetic stirrer speed at 600 rpm, and 10 minu...

Abbreviations: AIBN, 2,20-azo-bis-isobutyronitrile; ASE, Accelerated solvent extraction; CAR, Carboxen; DAD, Diode-array detector; DI-SPME, Direct-immersion solid-phase extraction; DSPE, Dispersive solid-phase extraction; EGDMA, Ethylene glycol dimethacrylate; ESE, Enhanced solvent extraction; ESI, Electrospray ionization; FD, Fluorescence detection; FLD, Fluorimetric detection; GC, Gas chromat...

Solid Phase Microextraction (SPME) uses a small volume of sorbent dispersed typically on the surface of small fibres, to isolate and concentrate analytes from sample matrix. After contact with sample, analytes are absorbed or adsorbed by the fibre phase (depending on the nature of the coating) until an equilibrium is reached in the system. The amount of an analyte extracted by the coating at eq...

Thallium is widely found in nature, but the only inorganic stones full of this element are crookesite and lorandit. It isalso found in pyrites of copper, lead and inorganic stones. The element and its compositions are toxic and harmful to theenvironment; therefore, its application requires caution and further research. It is important to develop sensitive andaccurate analytical methods to deter...

43 Solidified floating organic drop micro-extraction (SFODME) for simultaneous separation/pre-concentration and determination of cadmium by atomic absorption spectroscopy R. Parviz, M. Honari Department of Chemistry, Faculty of Science, Islamic Azad University Shahr-E-Rey Branch, Shahr-E-Rey, Iran Department of Plant Breading and Biotechnology, Agriculture and Natural Resources Faculty, Tehran ...

A new, rapid and sensitive microextraction technique named vortex-assisted liquid-liquid-liquid microextraction (VALLLME) is proposed. The complete extraction process involves two steps. First, a vortex-assisted liquid-liquid microextraction (VALLME) procedure was used to extract the analytes from a relatively large volume of sample (donor phase) to a small volume of organic solvent (intermedia...

A simple microextraction method based on solidification of a floating organic drop (SFOD) was developed for preconcentration of lead prior to its determination by electrothermal atomic absorption spectrometry (ETAAS). Ammonium pyrolidinedithiocarbamate (APDC) was used as complexing agent, and the formed complex was extracted into a 20 μL of 1-undecanol. The extracted complex was diluted with et...