Liquid-liquid extraction or solid-phase extraction followed by gas chromatography (GC) or high-performance liquid chromatography are traditional herbicide residue determination methods for environmental samples. Solid-phase microextraction (SPME) is a solventless, fast, and sensitive alternative herbicide residue extraction method that can be applied to numerous environmental matrices. The obje...

A new, simple, rapid, sensitive and environmentally friendly ultrasound-assisted emulsification dispersive liquid–liquid microextraction (UAE-DLLME) has been developed for trace nickel Ni(II) separation preconcentration in environmental samples prior to spectrophotometric determination. The proposed method based on using non-ionic water-soluble surfactant Triton X-114 (TX-114) as a disperser so...

This study developed an acid hydrolysis coupled to a solid-phase microextraction method employing a semi-microcolumn liquid chromatography system, instead of enzyme hydrolysis with solid-phase extraction for the pretreatment of human urine samples, to detect urinary 1-hydroxypyrene (1-OHP). The complete separation and detection of urinary 1-hydroxyprene was performed using a high-performance li...

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...

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...