Solid phase extraction membrane

Rule G, Henion J. 1999. High-throughput sample preparation and analysis using 96-weU membrane solid-phase extraction and liquid chromatography—tandem mass spectrometry for the determination of steroids in human urine. J Am... 

Solid-phase extraction membrane. Solid-phase extraction cartridge. [Courtesy Alhech Associates,... 

RS Plumb, RD Gray, AJ Harker, SJ Taylor. Use of reduced sorbent bed and disk membrane solid-phase extraction for the analysis of pharmaceutical compounds in biological fluids, with applications in the 96-well format. J Chromatogr B 687 457 161, 1996. 

Plumb, R.S. Gray, R.D.M. Jones. C.M. "Use of Reduced Sorbent Bed and Disk Membrane Solid-Phase Extraction for the Analysis of Pharmaceutical Compounds in Biological Fluids, with Application in the 96-Well Format, J. Chromatogr. B 694, 123-133 (1997). 

Rule, G. Henion, J. High-Throughput Sample Preparation and Analysis Using 96-Well Membrane Solid-Phase Extraction and Liquid Chromatography-Tandem Mass Spectrometry for the Determination of Steroids in Human Urine, J. Am. Soc. Mass Spectrom. 10, 1322-1327 (1999). 

Senseman, S. A., Lavy, T. L., Mattice, J. D., Myers, B. M. and Skulman, B. W. 1993. Stability of various pesticides on membranous solid-phase extraction media. Environ. Sci. Tech., 27 516-519. 

Ill. Sojo, L. E. and Djauhari, J., Determination of chlorophenolics in waters by membrane solid-phase extraction comparison between Cig and activated carbon membranes and between modes of extraction and elution, J. Chromatogr. A, 840, 21-30, 1999. 

Chee, K. K., Wong, M. K., and Lee, H. K., Determination of organochlorine pesticides in water by membranous solid-phase extraction, and in sediment by microwave-assisted solvent extraction with gas chromatography and electron capture detector and mass spectrometric detection, J. Chromatogr. A, 736, 211-218, 1996. 

Bedendo GC, Carasek E. Simultaneous liquid-liquid microextraction and polypropylene microporous membrane solid-phase extraction of organochlorine pesticides in water, tomato and strawberry samples. J Chromatogr A 2010 1217 7-13. 

Saito described a quantitative spectrophotometric procedure for iron based on a solid-phase extraction using bathophenanthroline in a poly(vinyl chloride) membrane. ... 

In recent decades the development of preconcentration steps to be implemented prior to analytical determinations of trace level compounds has been explored in considerable depth. With a view to eliminating or at least minimising the use of organic solvents used in conventional liquid-liquid extraction, other methodologies have been developed, such as membrane extraction, solid-phase extraction, solid-phase microextraction, etc. 

C. Aguilar, P. BottuII and R. M. Marce, On-line and off-line solid-phase extraction with styrene-divinylbenzene-membrane extr action disks for determining pesticides in... 

The most widely employed techniques for the extraction of water samples for triazine compounds include liquid-liquid extraction (LLE), solid-phase extraction (SPE), and liquid-solid extraction (LSE). Although most reports involving SPE are off-line procedures, there is increasing interest and subsequently increasing numbers of reports regarding on-line SPE, the goal of which is to improve overall productivity and safety. To a lesser extent, solid-phase microextraction (SPME), supercritical fluid extraction (SEE), semi-permeable membrane device (SPMD), and molecularly imprinted polymer (MIP) techniques have been reported. 

Small molecule size-c Ecluslon chrmutography 441 Soap-film meter (GC) 4, 235 Solid-phase extraction 777 cartridges 777 membranes 780 optimization 777, 783 sorbents 778, 785 trace enrichment 777, 783 Solubility parameters 460 Solvatochromic parameters GC 191... 

Diffusive sampler Membrane extraction (MESI) Liquid-liquid extraction (LLE) Solid-phase extraction (SPE) SPE-PTV-GC Solid-phase microextraction (SPME) Headspace GC (SHS, DHS) Large-volume injection (LVI) Coupled HPLC-GC Membrane extraction (MESI) Difficult matrix introduction (DMI) Conventional solvent extraction methods 1 Pressurised solvent extraction methods Headspace GC (SHS, DHS) Thermal desorption (TD, DTD) Pyrolysis (Py) Photolysis Photon extraction (LD) Difficult matrix introduction (DMI)... 

Due to the predicted and previously detected low concentrations of pesticides in environmental samples (usually around the nanogram per liter level), a preconcentration step of the water samples is necessary prior to measurement. In this way, a preconcentration factor of several orders of magnitude (200-1,000-fold) is mandatory to reach the low detection limits necessary for the identification of pesticides, especially in complex wastewater samples. Also, the use of surrogate standards (e.g., triphenyl phosphate) added before the extraction step is a common practice in order to account for possible errors during the extraction process and for quantitative purposes. The commonly used extraction methods for polar compounds from water matrices involve isolation using liquid-liquid extraction (LLE) and solid-phase extraction (SPE), which are commented on below. Other methods such as semipermeable membrane devices (SPMD) are also mentioned. 

Endocrine disruptors are nowadays considered among the most important emerging pollutants in wastewater, but they are not actually monitored on-line. A recent study [48] described the implementation of a broad-spectrum analytical scheme for the screening of more than 200 compounds (endocrine disruptors, pharmaceutical compounds,...) in urban wastewater. For other specific organic compounds, a study concerning the improvement of immunoassays with a solid-phase extraction (SPE) membrane was reported for the on-site detection in soils and water of energetic materials (i.e. explosives) [49], but unfortunately it was not really tested for wastewater. 

Tap water Extract compound with solid-phase extraction technique that uses a membrane impregnated with reverse-phase particles elute with acetonitrile LC Low ppb (pg/L) 82-93 Hagen et al. 1990... 

The biological applications of NMR include the study of the structure of macromolecules such as proteins and nucleic acids and the study of membranes, and enzymic reactions. Newer methods and instruments have overcome, to a large extent, the technical difficulties encountered with aqueous samples and the analysis of body fluids is possible, permitting the determination of both the content and concentration of many metabolites in urine and plasma. NMR is not a very sensitive technique and it is often necessary to concentrate the sample either by freeze drying and dissolving in a smaller volume cm- by solid phase extraction methods. 

However, the solution obtained after denaturation might include, depending on the application, other components besides the liberated marker ( matrix ). If a small amount of target material is used in the binding assay, the quantity of remaining matrix will be so low that it hardly disturbs the quantitation and the sample can be measured directly by LC-MS without further sample preparation (e.g. membrane filtration or solid phase extraction [78]). 

Elimination of coextracted materials and concentration of tetracyclines have also been accomplished using mixed-phase extraction membranes with both re-versed-phase and cation-exchange properties (294,295), or solid-phase extraction columns packed with cation-exchange materials such as CM-Sephadex C-25 (301), aromatic sulfonic acid (310), and carboxylic acid (283, 300). For the same purpose, metal chelate affinity chromatography has also been employed. In this technique, the tetracyclines are specifically absorbed on the column sorbent by chelation with copper ions bound to small chelating Sepharose fast flow column (278-281, 294-296). 

S. Lubbad, S.A. Steiner, J.S. Fritz, and M.R. Buchmeiser, Metathesis polymerization-derived monolithic membranes for solid-phase extraction coupled with diffuse reflectance spectroscopy, J. Chromatogr. A, 1109(1) 86—91, March 2006. 

Solid-phase extraction uses a small volume of a chromatographic stationary phase or mole-cularly imprinted polymer23 (Box 26-2) to isolate desired analytes from a sample. The extraction removes much of the sample matrix to simplify the analysis. The opening of this chapter shows a solid-phase extraction membrane and extraction cartridges mounted on syringes. 

When samples contain high quantities of interfering material (e.g., sugars, colloids), a sample-cleanup procedure is recommended. A sample preparation with solid-phase extraction cartridges (C18) was found to be quite useful and effective (180,193). Prior to HPLC analysis, all samples should be filtered through a 0.45-/zm or smaller membrane filter. 

Up to now, most efforts have been directed towards the preparation of uniformly sized spherical MIP particles in the micrometre range. This is the obvious consequence of the need for this kind of materials as fillers for high-performance chromatographic columns, capillaries for electrophoresis, cartridges for solid-phase extractions and other applications requiring selective stationary phases. Additionally though, strategies for the preparation of other more sophisticated MIP forms, such as membranes, (nano)monoliths, films, micro- and nanostructured surfaces etc. 

Fluid from solid-phase extraction of wool was placed on simple screen-printed electrodes (an outer membrane was applied with an airbrush) [45]. The solvent was allowed to evaporate and, after an overnight incubation, the activity of the electrodes was measured quickly with reference to that of unexposed electrodes. It was possible to detect the presence of organo-phosphates which had been used to contaminate samples of untreated sheep wool (Fig. 28.3) (see Procedure 41 in CD accompanying this book). 

Subramanian and coworkers developed polymeric sorbents using different support materials (such as Merrifield chloromethylated resin, Amberlite XAD 16) and complexing ligands (amides, phosphonic acids, TTA), and evaluated their binding affinity for U(VI) over other diverse ions, even under high acidities. The practical utility of these sorbents was demonstrated using simulated waste solutions (220-222). Shamsipur et al. reported the solid-phase extraction of ultra trace U(VI) in natural waters using octadecyl silica membrane disks modified by TOPO (223). The method was found satisfactory for the extraction and determination of uranium from different water samples. 

Shamsipur, M. Ghiasvand, A.R. Yamini, Y. Solid-phase extraction of ultratrace uranium(VI) in natural waters using octadecyl silica membrane disks modified by tri-N-octylphosphine oxide and its spectrophotometric determination with dibenzoylmethane, Anal. Chem. 65 (1999)4892 1895. 

Izatt, R. M., Review of selective ion separations at B YU using liquid membrane and solid phase extraction procedures, J. Incl. Phenom. Mol. Rec. Chem., 29, 197-220, 1997. 

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