The extraction efficiency of stimulant drug, namely caffeine, was investigated using a 23 central composite design. values optimum condition were set at 468 ?L 1-dodecanol, 1 piece effervescent tablet, and 22 °C temperature. An enrichment factor calculated as 72 for 80 mL water sample. run time conducted in less than 6 min non-polar C18 column an isocratic mobile phase (methanol: 40:60 (v/v)) c...

a sensitive, selective and effective ionic liquid-based single drop microextraction technique was developed by using ionic liquid, 1-hexyl-3-methylimidazolium hexafluorophosphate, c6mimpf6, coupled with electrothermal atomic absorption spectrometry (etaas) for the determination of copper and silver in environmental samples. dithizone was used as chelating agent. several factors that influence t...

Bisphenol A (BPA), an alkylphenolic compound, is one of the most polluting and hazardous organic chemicals. Its routine detection is, however, still rather expensive due to high-cost equipment. In this context, we applied effect caused by BPA optical properties surfactant-stabilized silver nanoparticles further modified with use ammonia (AgNP-NH3) develop a simple quantitative approach for dete...

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...

the volatile components of citrus aurantium l. flowers were characterized by gc-ms with two different extraction techniques, hydrodistillation (hd) and ultrasonic-assisted headspace solid phase microextraction (ua-hs-spme). in the spme method, the volatile components of the samples, irradiated by ultrasonic radiation, were collected on a polydimethyl siloxane (pdms) commercial fiber as well as ...

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...