For a long time, sample preparation was unrecognized as a critical issue in the analytical methodology, thus limiting the performance that could be achieved. However, the improvement of microextraction techniques, particularly microextraction by packed sorbent (MEPS) and solid-phase microextraction (SPME), completely modified this scenario by introducing unprecedented control over this process....

Sample preparation is important for the isolation and concentration of desired trace components from complex matrices. Sample preparation is the most labor-intensive and error-prone process in analytical methodology, and greatly influences the reliable and accurate determination of analytes. The integration of sample preparation with various analytical instruments is most conveniently achieved ...

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...

Size effects during phase transformations change the composition of coexisting phases in ternary mixtures. The consequence is a distribution coefficients components, which interest for microextraction. concentration dependence degree extraction separable mixtures (aniline-methylcyclopentane-hexane and water-phenol-toluene) submicron drops was simulated by methods equilibrium chemical thermodyna...

BACKGROUND AND THE PURPOSE OF THE STUDY Ofloxacin is a quinolone synthetic antibiotic, which acts against resistant mutants of bacteria by inhibiting DNA gyrase. This antibacterial agent is widely used in the treatment of respiratory tract, urinary tract and tissue-based infections, which are caused by Gram-positive and Gram-negative bacteria. In this work, an efficient modified ionic liquid co...

An efficient and environmentally friendly sample preparation method based on the application of hydrophobic 1-Hexylpyridinium hexafluorophosphate [Hpy][PF(6)] ionic liquid (IL) as a microextraction solvent was proposed to preconcentrate terazosin. The performance of the microextraction method was improved by introducing a common ion of pyridinium IL into the sample solution. Due to the presence...

The requirement to monitor the chemical quality of water has become one of the major issues in environmental analytics. Ionmobility spectrometry (IMS), a fast, sensitive method traditionally used in security and military applications, is also suitable for environmental analysis and detection of organic pollutants from aqueous matrices, when combined with advantageous methods to isolate analytes...

Phthalate esters are endocrine disrupters or mutagens. They are widely used as plasticizers and can be usually found in environmental samples, such as food, soil and polluted air. However, it is difficult to directly determine phthalate esters owing to their relatively low concentration and complex matrices. Therefore, preconcentration and separation have become increasingly important. In recen...

In this study, an analytical methodology based on a combination of dispersive liquid–liquid microextraction with laser-induced breakdown spectrometry was evaluated for simultaneous pre-concentration, speciation and detection of Cr. The microextraction procedure was based on the injection of appropriated quantities of 1-undecanol and ethanol into a sample solution containing the complexes formed...