Question

Phosphoric acid is a polyprotic acid in the chromatography system, is this system capable of detecting organic acids such as lactate? Could this capability change based on the pH of the system? Explain.

Answer 1

yes, the phosphoric acid is cable of detecting lactate.

by Reverse phase HPLC , lactic acid ( lactate)can be determined by using phosphoric acid solution at pH 2.5 as mobile pase( 0.01mol/L).This methos id accurate and rapid for the lactic acid determination.

with varying in pH of the mobilephase system the elution of peaks may effect based on the type of compound , here lactic acid is carboxylic acid and the pH may affect the separation of carboxylic group and hydroxyl group.