Determination of organophosphorous pesticides in wastewater samples using binary-solvent liquid-phase microextraction and solid-phase microextraction: A comparative study

Principais técnicas de preparo de amostra para a determinação de resíduos de agrotóxicos em água por cromatografia líquida com detecção por arranjo de diodos e por espectrometria de massas

“…Basheer et al 67 estudaram a influência do pH da amostra na extração de agrotóxicos organofosforados por SPME e constataram que o pH também é um parâmetro importante que deve ser ajustado. O grau de ionização dos analitos afeta sua solubilidade em água e, portanto, sua adsorção na fibra.…”

Highlights of Mass Spectrometric Methodologies in Environmental Pollution

“…The chemical-biological and slow degradation properties together with unscrupulous and extensive uses of this class of pesticides have led to the occurrence of several cases of environmental pollution and food contamination. Basheer et al, (2007) developed a simple binary solvent-based two-phase hollow fiber membrane (HFM)-protected liquid-phase microextraction (BN-LPME) technique followed by analysis under GC/MS selective ion monitoring mode. This method was compared with a classical SPME procedure and both techniques were applied in water samples to determine the presence of six moderately polar organophosphorus pesticides (OPPs): triethylphosphorothioate, thionazin, sulfotep, phorate, disulfoton, methyl parathion and ethyl parathion.…”

Analysis of Matrine Alkaloids in Human Urine by Hollow Fiber Liquid-phase Microextraction with High-performance Liquid Chromatography

“…In three-phase LPME, the unionized analytes are first extracted from the aqueous sample, entering into a thin layer of an organic phase inside the wall pores of the hollow fiber, and are then further extracted into the lumen of the hollow fiber, which holds a small volume of an aqueous-based acceptor phase. HF-LPME methods have been applied widely in many fields, such as pesticides, 15,16 tetracycline antibiotics, 17 diuretics 18 and other analytes. [19][20][21] In this study, a HF-LPME method was used to extract matrine alkaloids from urine samples for the first time.…”