Determination of Components in Eye Lotion by Capillary Electrophoresis.

Abstract

Capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) with sodium dodecyl sulfate (SDS) as an anionic carrier were applied to the analysis of nine principal components of eye lotion. Simultaneous separation of these components except cyanocobalamin (VB12), which has the same migration time with that of electroosmotic flow, was achieved by CZE using a 72 cm×50 μm i.d. fused silica capillary tube filled with 20 mM borate buffer (pH 10) at 25 kV DC voltage with UV detection at 200 nm. Under these conditions, the peak of chondroitin sulfate (CS) was overlapped with that of aspartic acid in case the latter was contained in the sample as a co-existing component. However, when pH was decreased to 9, CS was separated from other components and also from aspartic acid, and gave a more shapely peak. VB12 could be separated from other components by MEKC with 20 mM borate buffer (pH 10) containing 40 mM SDS. The applicability to the determination of nine principal components of eye lotion is demonstrated.