Extraction and quantification

LiGGiNS J, GRIMWOOD R, BINGHAM s A (2000) Extraction and quantification of lignan ph)doestrogens in food and human samples. naZ Biochem. 287 102-9. 

The wide distribution of chlorophylls throughout the plant kingdom facilitates the scrutiny of chlorophyll-rich vegetables for human nutrition with a view to their direct consumption. However, until now, little standardized information was available in the literature regarding the absolute total chlorophyll contents and the ratios of chlorophylls a and b in raw materials. The different analytical methods of extraction and quantification and the lack of data about moisture contents (that may vary considerably among varieties and preparations) can also influence the final contents of pigments. These factors have largely contributed to the discrepancies found in similar food samples. 

DNA Extraction and quantification Indicates total biological structure time-consuming expensive equipment determined in nonstandard laboratory with specialized equipment difficult for complete extraction Arbeli and Fuentes (2007)... 

Artemisinin, a tetracyclic 1,2,4-trioxane isolated from Artemisia annua L., is currently recommended as a first-line agent against Plasmodium falciparum malaria. Artemisinin and its synthetic derivatives have also been shown to be promising prototypes for the development of new antiproliferative agents. This chapter presents the recent advances on the analytic methods for extraction and quantification of artemisinin from A. annua plants as well as the biological properties of this natural product. 

FDA) for use in humans to treat malaria because this drug is considered a safe drug with few side effects.These features prompted various scientists around the world to evaluate the potential of artemisinin (1) and derivatives to control cancer cells proliferation. This chapter reviews the recent advances on analytical methods for extraction and quantification of artemisinin (1) from A. annua. Examples of artemisinin-derivatives with antiproliferative activities are listed, describing the structure-activity relationships of 96 compounds. This knowledge is essential for future development and use of artemisinin derivatives in cancer therapy. The mechanism of action of artemisinin and derivatives on cancer cells have been well reviewed in literature and therefore is not discussed in this chapter. 

Analytic Methods for Artemisinin Extraction and Quantification from Artemisia annua... 

The adaptation of methods for lipid extraction and quantification by colorimetric determination of either ester or cholesterol in egg yolk with some contamination of egg white is described. Results are compared with those obtained by a conventional enzymatic determination. 

MH Akhtar, M Wong, SRH Crooks, A Sauve. Extraction of incurred sulphamethazine in swine tissue by microwave assisted extraction and quantification without clean-up by high performance liquid chromatography following derivatization with dimethylaminobenzaldehyde. Food Additiv Con-tarn 15 542-549, 1998. 

Further speculation however is unwarranted at this time as it is likely that choice of body site, the nature of induction of xerosis (natural versus surfactant/solvent induced), differing methods of RT-PCR and filaggrin extraction and quantification protocols may all contribute to the current lack of clarity in our understanding. 

Extraction and Quantification of the Residue. When gas chro-matography is used as the method of quantification, extraction provides the most information of any of the residue analysis methods since both qualitative and quantitative information can be obtained. In this way any changes in ratios or the presence of degradation products in the residue can also be detected. 

Kuhnle, G. Dell Aquila, C. Low, Y. Kussmaul, M. Bingham, S. 2007. Extraction and quantification of phytoestrogens in foods using automated solid-phase extraction and LC/MS/MS. Anal. Chem. 79 9234-9239. 

Liggins, J., Bluck, L.J., Coward, A., and Bingham, S.A. 1998. Extraction and quantification of daidzein and genistein in food. Anal. Biochem. 264 1-7. 

A first Interlaboratory comparison on PCBs in sludges was performed In 1983- 84. The results have shown the importance of the extraction and quantification steps for the comparability of results obtained by different laboratories. A second interiaboratory comparison was performed in 1987-88 to test these specific points of the analytical process. An other aim was to investigate the capability of european laboratories to analyse other organic micro-pollnlants in sewage sludges. Three types of samples were sent to the laboratories ... 

Skopec, Z. V., Clark, R., Harvey, P. M. A., and Wells, R. J., Analysis of organophosphorus pesticides in rice hy supercritical fluid extraction and quantification using an atomic emission detector, J. Chromatogr. Set, 31, 445-449, 1993. 

In some cases SFE, MAE, or PFE cannot be used because of the weakness of the targeted compounds. An analytical method based on a soft extraction procedure was applied to the extraction and quantification of the OXA and ESA acid metabolites of the acetochlor and metolachlor herbicides in soil samples. The extractions were performed by using 50 or 100 g of soil and a solvent extraction method with a mixture of acetonitrile/water (60/40) in acid medium. Each of the four different soil matrixes was spiked in triplicate with standards of each degradation compound, at three concentration levels between 2 and 80 /rg/kg. The average recoveries range from 90 to 120% for both metabolites, with relative standard deviations lower than 15%. The limits of detection were about 0.5 and 2 /rg/kg for the ESA and the OXA metabolites, respectively. Sample preparation and chromatographic analysis of acidic herbicides in soils and sediments were recently reviewed by Macutkiewicz et al. ... 

Mohamed R, Richoz-Payot J, Gremaud E, Mottier P, YRmaz E, Tabet JC, Gut PA, Advantages of molecularly imprinted polymers LC-ESI-MS/MS for the selective extraction and quantification of chloramphenicol in milk-based matrixes. Comparison with a classical sample preparation. Anal. Chem. 2007 79 9557-9565. 

Barbarino, E. and Lourengo, S. O. (2005). An evaluation of methods for extraction and quantification of protein from marine macro- and microalgae. /. Appl. Phycol. 5,447- 0. 

Cassells, N.P., et al., Microtox testing of pentachlorophenol in soil extracts and quantification by capfllary electrochromatography (CEC)—A rapid screening approach for contaminated land, Chemosphere, 40, 609, 2000. 

Two compounds are currently of particular interest in paper and board. Diisopropyl naphthalene (DIPN) is a mixture of isomers that until recently were widely used in carbonless copy papers as ink solvents. Although it is currently being replaced it occurs as a persistent contaminant in recycled paper and board. Various studies have shown that it is able to migrate from paperboard into food. There is a draft CEN analytical method available. This method involves acetone extraction and quantification by GC-MS using diethyl naphthalene as an internal standard. There is currently no limit for DIPN but levels are being monitored to reduce concentrations in recycled paperboard. 

Comparison of extraction and quantification methods of perfluorinated compounds in human plasma, serum, and 98. 

To verify the suitability of an approach that ensures transferability through recovery rates for complete validation of the extraction and quantification steps, high levels of accuracy should always be accompanied by ideal repeatability in different samples combining precision and accuracy. Good recovery rates (higher than... 

Paixao, J.A. Stamford, T.L.M. Lacteal matrices A single guide for extraction and quantification of fat soluble vitamins. J. Liq. Chromatogr. Relat. Technol. 2002, 25 (2), 217-239. 

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