نتایج جستجو برای: liquid microextraction
تعداد نتایج: 219504 فیلتر نتایج به سال:
PURPOSE Fluoxetine is the most prescribed antidepressant drug worldwide. In this work, a new dispersive liquid-liquid microextraction (DLLME) method combined with spectrofluorimetry has been developed for the extraction and determination of FLX in pharmaceutical formulations and human urine. METHODS For FLX determination, the pH of a 10 mL of sample solution containing FLX, was adjusted to 11...
A simple and efficient method for speciation and determination of iron in different water samples was developed. The method is based on ionic liquid ultrasound assisted dispersive liquid–liquid microextraction (IL-USADLLME) followed by spectrophotometric determination. Fe(II) is complexed with 2,4,6-tri(2’-pyridyl)-l,3,5-triazine (TPTZ), neutralized through ion pair formation with sodium dodecy...
Vortex-assisted liquid-liquid microextraction (VALLME) coupled with high-performance liquid chromatography (HPLC) is proposed here for the rapid determination of octanol-water partitioning coefficients (Kow). VALLME uses vortex agitation, a mild emulsification procedure, to disperse microvolumes of octanol in the aqueous phase thus increasing the interfacial contact area and ensuring faster par...
2 Introduction An important part of any analytical process is sample preparation, which involves isolation and preconcentration of various analytes of interest.1 Liquid–liquid extraction (LLE) is one of the oldest pretreatment procedures and because of its simplicity and low cost is commonly used. However, conventional LLE requires large volumes of high-purity solvents, which are often expensiv...
An efficient, rapid, simple, and highly selective dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME-SFOD), combined with flame atomic absorption spectrometry was developed for preconcentration and determination of trace amounts of cobalt in water samples. In this method, an appropriate mixture of acetone and 1-undecanol was injected rapidly into th...
Two modes of liquid-phase microextraction (LPME) combined with hollow fiber (HF) were developed for gas chromatography/mass spectrometry (GC/MS). Both methodologies, that is, static LPME with HF and dynamic LPME with HF, involved the use of a small volume of organic solvent impregnated in the hollow fiber, which was held by the needle of a conventional GC syringe. In static LPME/HF, the hollow ...
Ion pair dispersive liquid- liquid microextraction (IP-DLLME) method combined with flame atomic absorption spectrometry was proposed for the determination of trace amounts of copper(II). By using pyrocatechol violet as chelating agent and cetyltrimethyl ammonium bromide as an ion pairing agent, the trace amount of copper(II) was extracted in chloroform. The factors influencing the formation cop...
A simple and rapid vortex assisted ionic liquid based liquid-liquid microextraction technique (VALLME) was proposed for preconcentration of trace levels of cadmium. According to this method, the extraction solvent was dispersed into the aqueous samples by the assistance of vortex agitator. Cadmium preconcentration was mediated by chelation with the 8-hydroxyquinoline (oxine) reagent and an IL, ...
For the first time, hollow-fiber liquid-phase microextraction combined with high-performance liquid chromatography-ultraviolet was used to extract trans,trans-muconic acid, in urine samples of workers who had been exposed to benzene. The parameters affecting the metabolite extraction were optimized as follows: the volume of sample solution was 11 mL with pH 2, liquid membrane containing dihexyl...
Recent increased demand for stingless bee honey in Malaysia have stimulated alternative methods to increase honey yields by using plastic cups as artificial honey pots within the beehives. However, honey’s acidity may lead to possible migration of plastic additives, where prolonged consumption may affect body’s physiological responses. This study was carried out to determine the presence of dib...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید