Direct analysis of samples, regardless their origin, is desirable although for the majority of cases unfeasible on account of the complexity of the sample matrix, inadequate concentration of the target analytes, or even incompatibility with the detector. In these cases, a sample pretreatment step is required for interference removal and analytes separation/preconcentration. Despite valuable adv...

A single-drop microextraction (SDME) was developed for the analysis of volatile fatty acids (VFAs) (C2-C7) in water by gas chromatography (GC) with flame ionization detection. The significant parameters affecting the SDME performance such as selection of microextraction solvent, extraction time, stirring rate, sample pH and temperature, and ionic strength were studied and optimized. To lower li...

This paper describes a new approach for the determination of amitriptyline in wastewater by ionic liquid based immersed droplet microextraction (IL-IDME) prior to high-performance liquid chromatography with ultraviolet detection. 1-Hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]) was used as an ionic liquid. Various factors that affect extraction, such as volume of ionic liquid, sti...

Residual solvents (RS) are not desirable substances in the final pharmaceutical product and their acceptable limits have been published in pharmacopoeias and ICH guidelines. The intension of this paper was to review and discuss some of the current analytical procedures including gas chromatographic (GC) and other alternative techniques which are used for residual solvents determination. GC meth...

We have developed a new method for single-drop microextraction (SDME) for the preconcentration of organochlorine pesticides (OCP) from complex matrices. It is based on the use of a silicone ring at the tip of the syringe. A 5 μL drop of n-hexane is applied to an aqueous extract containing the OCP and found to be adequate to preconcentrate the OCPs prior to analysis by GC in combination with tan...

In this work, two approaches based on Dispersive Liquid-Liquid MicroExtraction (DLLME) and Dispersive Liquid-Liquid MicroExtraction based on Solidification of Floating Organic Drop (DLLME-SFO) were compared for the extraction and preconcentration of crocin from saffron and biological samples. Different DLLME and DLLME-SFO parameters influencing the extraction efficiency were studied and opt...

dispersive liquid-liquid microextraction technique based on solidification of a floating organic drop (dllme-sfo) combined with flame atomic absorption spectrometry was developed for determination of thallium in water sample. an appropriate mixture of acetone and 1-undecanol was rapidly injected into an aqueous sample containing tlcl4- which forms an ion pair with brilliant green reagent and as...