| RESEARCH |
CO2 used to process carbs In a new demonstration of carbon dioxide's utility as a "green" solvent, postdoc Poovathinthodiyil Raveendran, assistant chemistry professor Scott L. Wallen, and their colleagues at the University of North Carolina, Chapel Hill, report that carbohydrates and other macromolecules can be readily separated, crystallized, and otherwise processed in gaseous, liquid, and supercritical CO2 (Green Chem. 2005, 7, 129). Carbohydrates generally are insoluble in CO2, but Raveendran and Wallen previously have shown that the compounds can be made soluble by replacing CO2-phobic hydroxyl groups with acetate groups. One process the researchers have focused on is using supercritical CO2 (110 bar and 40 ºC) to prepare single crystals of acetylated -D-galactose (-Gal) for X-ray analysis. They believe that this is the first time supercritical CO2 has been used for bulk crystallization. The researchers also used CO2 to prepare dispersions of a protein (cytochrome C) and a drug (ibuprofen) in the acetylated -Gal, and they made porous acetylated cyclodextrin materials for use as sustained-release drug carriers. |
|
Want more information ? Interested in the hidden information ? Click here and do your request. |