This paper describes a simple and quick method for sampling and also for carrying out the preconcentration of pesticides in environmental water matrices using two-phased hollow fiber liquid phase microextraction (HF-LPME). Factors such as extraction mode, time, solvents, agitation, and salt addition were investigated in order to validate the LPME method. The following conditions were selected: ...

polyvinylidene fluoride/polyvinylpyrrolidone (pvdf/pvp) hollow fiber membranes were fabricated by dry-jet wet-spinning process. the correlated effects of the air gap length and pvp concentration ((1) the air gap length effect at the low and high pvp concentration in the dope solutions, as well as (2) the effect of the pvp concentration at the same air gap length) on the cross-section structure ...

membrane technology is used to separate water or solvents from salts or pollutants. this technique could be used for water treatment. for using of polyether sulfone (pes) hollow fiber membranes in water treatment processes, the pes hollow fiber membranes were prepared by dry-wet spinning method and heated in an oven at: 120°c, 150°c and 180°c. the effect of heating on performance of membranes w...

In this study, hollow fiber liquid phase microextraction (HF-LPME) coupled with highperformanceliquid chromatography (HPLC) with UV detection was applied for preconcentrationand determination of Diclofenac sodium in biological fluids. Parameters affecting the extractionprocess including pH of donor phase and acceptor phase, type of extraction solvent, stirring rate,extraction time, and salt add...

In high-throughput ultrasonication enhanced hollow-fiber liquid-phase microextraction (H-U-HF-LPME), ultrasonication was introduced into HF-LPME to enhance the mass transfer rate of the analytes in the two immiscible liquid phases, which resulted in a very short time for extraction equilibrium and a high-throughput analysis. Several parameters were investigated and optimized (such as extraction...

Surfactant-enhanced hollow fiber liquid phase (SE-HF-LPME) microextraction was applied for the extraction of melamine in conjunction with high performance liquid chromatography with UV detection (HPLC-UV). Sodium dodecyl sulfate (SDS) was added firstly to the sample solution at pH 1.9 to form hydrophobic ion-pair with protonated melamine. Then the protonated melamine-dodecyl sulfate ion-pair (M...

A simple and highly sensitive method that involves miniaturized hollow fiber assisted liquid-phase microextraction (HF-LPME) with in situ acyl derivatization and GC-MS was developed for the determination of benzophenone (BP) and related compounds in human urine samples. The limits of detection (S/N = 3) and quantification (S/N > 10) of BPs in human urine samples are 0.01 to 0.05 and 0.05 to 0.2...

A method termed hollow fiber liquid phase microextraction (HF-LPME) was utilized to extract three chlorophenols, 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP), separately from water. The extracted chlorophenols were then separated, identified, and quantified by UV-Vis spectrophotometry with photodiode array detection (UV-Vis/DAD). In the study, experi...