Solid waste, including petroleum based waste oils, transformer oil or mineral oil are screened for the presence of polychlorinated biphenyls (PCBs). The analysis is typically performed by GC-ECD or GC-MS after clean-up using column chromatography, solid phase extraction (SPE), or dispersive solid phase extraction (d-SPE). Clean-up on silica or acidified silica removes polar constituents that ca...

A method is developed for the determination of melengestrol acetate in bovine fat tissue at or less than the established tolerance level of 25 ppb. The procedure uses a combination of supercritical fluid extraction (SFE) and solid-phase extraction (SPE) techniques to produce an extract suitable for analysis with either high-performance liquid chromatography with ultraviolet detection or gas chr...

Simultaneous quantitative analysis of 10 indole compounds, including indole-3-acetic acid (IAA, one of the most important naturally occurring auxins) and some of its metabolites, by high performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) after solid-phase extraction (SPE) was reported for the first time. The analysis was carried out using a reverse phas...

The most important step for Paraquat analysis in post-mortem human blood (PMB) is its extraction from the specimens, as Paraquat is insoluble in organic solvents due to its ionic form. The most common extraction method, solid phase extraction (SPE), has been used for the extraction of Paraquat from PMB. However, SPE procedures are somewhat time-consuming, and resulted in unsatisfactory recovery...

A liquid chromatographic method with comfirmation by capillary electrophoresis was used to determine 12 sulfonylurea herbicides in agricultural water. Analysis of 3 different water matrixes fortified at 2 levels gave good recoveries with adequate sensitivity at the 0.1 ppb level. A portion of the water was acidified with acetic acid and loaded onto an RP-102 solid-phase extraction (SPE) cartrid...

A simple, semi-automated, microcolumn solid-phase extraction (SPE) system is optimized for the extraction, preconcentration and HPLC analysis of seven different explosives and explosive derivatives contaminating seawater, river water and well water samples. The microcolumns were constructed from 1/16 in. O.D. PTFE tubing (1 in.=2.54 cm) packed with 0.5-1.5 mg of SPE material. LiChrolut EN or Po...

solid phase extraction (spe) cartridge embedded with octadecyl c18 chain bounded to silica particles were used for the isolation and trace enrichment of pesticides from water samples collected from cotton, rice growing and municipal areas. the eluents were analyzed with high performance liquid chromatography (hplc) using methanol (100%) as mobiles phase at different uv-visible wavelengths. ddt ...

A method using ultrasonication extraction and solid phase extraction (SPE) clean-up for determination of US EPA 16 priority pollutant polycyclic aromatic hydrocarbons (PAHs) in soils by reversed-phase liquid chromatography (RP-LC) with ultraviolet (UV) absorption detection was studied. Separation and detection of the 16 PAHs were completed in 31 min by RP-LC with a C18 column (Bakerbond PAH 6 P...

Many modern analytical methods deal with the trace-level determination of compounds of interest in highly complex environmental samples by means of chromatographic techniques. The introduction of a “clean” sample into an analytical instrument can make analyses easier and prolongs the equipment life. The use of solid-phase extraction (SPE) has grown and is a fertile technique of sample prepa...

Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the traditional LLE method. High performance thin layer chromatography (HPTLC) has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over ...