Ion chromatographic determination of sugar phosphates in physiological samples

Ion chromatography is shown to be capable of simultaneous determination of biologically important anions. Application of this technique is illustrated for the separation and quantification of the major anions present in rat brain and liver tissues. Sugar phosphates and carboxylic acids are separated on high-performance anion-exchange columns and are detected using chemically suppressed conductivity. Detection limits range from 20 to 100 pmol for the anions tested, including inositol phosphates, lactate, pyruvate, glucuronic acid-1-phosphate, fructose-6-phosphate and glucose-6-phosphate. The coefficient of variation for the determination of most anions was in the range 5-10%. Many of these anions are either difficult to separate with other methods, or require expensive radiochemical techniques for detection. This method should be applicable to other biological studies, from the flow of carbons in photosynthesis to the study of synaptic transmission.