Compatibility of cloud point extraction with gas chromatography: Matrix effects of Triton X-100 on GC-MS and GC-MS/MS analysis of organochlorine and organophosphorus pesticides.

Cloud point extraction is an environmentally benign and simple separation/concentration procedure that can be regarded as an alternative to classical liquid-liquid extraction. In the current work, it was studied the compatibility of cloud point extraction followed by back-extraction in low volume of organic solvent with gas chromatography-mass spectrometry (GC-MS and GC-MS/MS). Triton X-100 was preferred than Triton X-114 as a surfactant to produce the clouding phenomenon and hexane or isooctane was found to be appropriate organic solvents which can be used at the back-extraction step.

Serum selenium concentration in patients with autoimmune thyroid disease.

Abstract.

MSIS-МP-АЕS determination of As and Sb in complex matrices by magnetic nanoparticles-assisted hydride generation.

The advantages of the microwave plasma atomic emission spectrometry (MP-AES) for hydride generation (HG) by means of modified Multi Mode Sample Introduction System (MSIS®) have been revealed for analysis of As and Sb in complex real samples. Two main outcomes have been achieved: (i) reliable analysis and higher tolerability to less diluted matrices and (ii) a multifold reduction in the methodological limits of detection (MLOD). For the first time in real samples analysis the HG is assisted by silica-coated magnetic nanoparticles (MNPs) (∼2 mg mL MnFeO@SiO) added to the hydrogenation reagent stream (1.

Determination of calcium, iron and manganese in moss by automated discrete sampling flame atomic absorption spectrometry as an alternative to the ICP-MS analysis.

An automated, fast and reliable procedure has been developed for flame atomic absorption analysis of Ca, Fe and Mn in moss. The method is suitable for routine analysis of a large number of moss samples and allows sequential determination of all three elements in the same solution. In order to inhibit the matrix interference on Ca and to level the diverse analytical behaviour of the moss matrix, approximately 1% La was added to both samples and standard solutions as well.