Ion-exchange displacement chromatography has been adapted to centrifugal partition chromatography. The use of an ionic liquid, benzalkonium chloride, as a strong anion-exchanger has proven to be efficient for the preparative separation of phenolic acid regioisomers. Multigram quantities of a mixture of three hydroxycinnamic acid isomers were separated using iodide as a displacer. The displaceme...

Column chromatography has evolved to provide a rapid and effective alternative to more laborious methods for preparing high-quality DNA, such as CsCl-gradient centrifugation. This unit describes the use of a column made of a unique anion-exchange resin that selectively binds nucleic acids, allowing rapid separation of DNA from contaminating RNA, proteins, carbohydrates, and metabolites. The pro...

A mixture of a carhoxylic acid type of cation exchange resin and a weakly basic anion exchange resin has been used successfully to control the edema of 42 patients wvith congestive heart failure andl the ascites of 14 patients with cirrhosis of the liver. Approximately one-third of the cation exchanger was supplied in the potassium cycle. Inclusion of the anion exchange resin resulted in a grea...

Simultaneous measurements of all major electrolytes including HCO3(-) and H+ as well as water demonstrated that fluids absorbed by the anterior intestine of the marine gulf toadfish under in vivo-like conditions on an overall net basis are hypertonic at 380 mOsm and acidic ([H+] = 27 mM). This unusual composition of fluids absorbed across the intestinal epithelium is due to the unusual intestin...

LEVEL: INTERMEDIATE C hromatography columns can become contaminated by a variety of protein and nonprotein species during a purification campaign. Consequences of column contamination include an increase in backpressure, loss of signal resolution, altered product yield, and medium discoloration. Common chromatographic contaminants include • residual proteins • nucleic acids • lipids • endotoxin...

Two distinct Cl/anion exchange activities (Cl/HCO(3) and Cl/OH) identified in apical membranes of rat distal colon are distributed in cell type-specific patterns. Cl/HCO(3) exchange is expressed only in surface cells, whereas Cl/OH exchange is localized in surface and crypt cells. Dietary Na depletion substantially inhibits Cl/HCO(3) but not Cl/OH exchange. We determined whether anion exchange ...

Anion-exchange membrane water electrolyzers (AEMWEs) are prepared as catalyst-coated membranes using varying amounts of ionomer in the catalyst layers.