COMPLETE RESOLUTION OF IMIDODIPEPTIDE MIXTURES IN URINE OF PROLIDASE-DEFICIENT PATIENTS USING MICELLAR ELECTROKINETIC CHROMATOGRAPHY

The use of capillary zone electrophoresis as an efficient method for t he identification of urinary imidodipeptides of prolidase-deficient pa tients has already been reported. However, owing to the complexity of the components excreted, the resolution of electrophoretic patterns ob tained was poor. Here we examine the use of micellar electrokinetic ch romatography to enhance peak resolution in order to obtain better insi ght into the electropherograms of patients' urine. The usefulness of s odium dodecyl sulphate as surfactant is reported: refined electrophero grams were achieved using 35 mM sodium berate, pH 8.3 containing 65 mM sodium dodecyl sulphate. Almost all peaks were baseline separated, co llected and sequenced. This allowed us to define the exact imidodipept ide composition of patients' urine. The possibility of identifying and thus quantifying each single peak means that comparison of urinary im idodipeptide excretion patterns from different patients can be made an d the hypothesis that peptide patterns can be correlated with differin g clinical severity can be investigated.