Ion exchange chromatography purification

Water Preconcentration by ion-exchange chromatography purification by ion-exchange and solvent extraction NAA and U) No data No data Gladney et al. 1983... 

The strategy for the synthesis of phosphinate 54a or 54b involves the activation of the phosphoms atom into the P reactant, followed by successive reactions with a Michael acceptor (ethyl acrylate or diethyl maleate), dibromoethane, and an esterification using triethyl orthoformate. The incorporation of the amino acid group accomplished by nucleophilic substitution of the anion of the diethylaceta-midomalonate yielded the branched phosphinates in 50-77% yield. The final deprotected compounds were obtained in 11-21% yield after acidic deprotection and decarboxylation and they were purified by ion exchange chromatography. Compound 54b was synthesized by alkylation of the phosphonite intermediate with acetamidoacrylic acid, followed by acidic deprotection and ion exchange chromatography purification (Scheme 8). 

Hydroxymethyl phosphinates 56 and 57 were obtained starting from phosphinic acid 49a. According to the previous methodology, the silyl-Abramov reaction on various aldehydes led to the formation of the addition products. Acidic deprotection and ion exchange chromatography purification afforded the desired compounds 56 or 57 (Scheme 11). 

The resuspended and formulated Fraction II precipitate normally contains some aggregated IgG and trace substances that can cause hypotensive reactions in patients, such as the enzyme prekail ikrein activator (186). These features restrict this type of product to intramuscular adininistration. Further processing is required if products suitable for intravenous adininistration are required. Processes used for this purpose include treatment at pH 4 with the enzyme pepsin [9001-75-6] being added if necessary (131,184), or further purification by ion-exchange chromatography (44). These and other methods have been fiiUy reviewed (45,185,187,188). Intravenous immunoglobulin products are usually suppHed in the freeze-dried state but a product stable in the solution state is also available (189). 

Amino acids have high melting or decomposition points and are best examined for purity by paper or thin layer chromatography. The spots are developed with ninhydrin. Customary methods for the purification of small quantities of amino acids obtained from natural sources (i.e. l-5g) are ion-exchange chromatography (see Chapter 1). For general treatment of amino acids see Greenstein and Winitz [The Amino Acids, Vols 1-3, J.Wiley Sons, New York 1961] and individual amino acids in Chapters 4 and 6. 

Preparation by fermentation of Saccharomyces cerevisiae (baker yeast) with addition of L- or DL-methionine, lyse of cells with ethyl acetate and purification by ion-exchange chromatography. 

Early measurements of " Th were on seawater samples and Th was co-precipitated from 20-30 L of seawater with iron hydroxide (Bhat et al. 1969). This procedure may not recover all of the " Th in the sample, and an alpha emitting Th isotope (e g., °Th or Th) is added as a yield monitor. Following chemical purification of the Th fraction by ion exchange chromatography, the Th is electrodeposited onto platinum or stainless steel planchets. The planchets are then counted in a low background gas-flow beta detector to measure the beta activity and subsequently with a silicon surface barrier detector to determine the alpha activity of the yield monitor. The " Th activity is thus determined as ... 

Puma, P., Duffey, D., and Dawidczyk, P., U.S. Patent appl. 94,944, Purification of oligodeoxyribonucleotide phosphorothioates using DEAE-5PW anion ion-exchange chromatography and hydrophobic interaction chromatography, 1994. 

Torres, J.L., Piera, E., Infante, M.R., Clapes, P. (2001). Purification of non-toxic, biodegradable arginine-based gemini surfactants, bis(Args), by ion exchange chromatography. Prep. Biochem. Biotechnol. 31(3), 259-274. 

Ion-exchange chromatography may be used for either purification of an individual component or fractionation of a mixture. In order to isolate a particular component... 

G. Wang, Isolation and purification of phycoeryhtrin from red alga Gracilaria verrucosa by expanded-bed-adsorption and ion-exchange chromatography. Chromatogaphia 56 (2002) 509-513. 

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