Potentiometric detection for capillary electrophoresis: Determination of organic acids

摘要: A potentiometric detector was developed for CE and applied to the determination of aliphatic carboxylic acids (up C10). The electrodes used were “coated wire” type. Insulated Cu wires (from 100 250 μm diameter), with only tip wire exposed, directly coated “liquid membrane” phases. quaternary ammonium salt a lipophilic macrocyclic pentaamine as carrier molecules. positioned at end capillary (“wall-jet” type construction). best compromise between separation detection characteristics obtained HEPES buffer system. Detection limits fmol (injection by electromigration). Calibration curves linear in range 0−25 pmol injected. behavior system is discussed theoretically.