Silicic acid chromatography of organic acids in blood cells and biological fluids.

The separation of organic acids and their elution from silicic acid columns and their quantitative measurement by color change of buffered indicator, a technique mechanized by Kesner and Muntwyler, are applicable to the study of biological materials. As little as 25 g of acid can be measured. Elution times and color yield in terms of peak areas obtained with the commercial apparatus are given for 25 organic acids. Blood, plasma, red cells, and spinal fluid have been analyzed; specimens were either untreated or extracted with ether. The most abundant acids detected were propionic, lactic, hippuric, and acetic. Methylmalonate was measured in body fluids and blood cells of patients with methylmalonic acidemia and pernicious anemia. Concentrations of organic acids in blood and spinal fluid are given.