DETERMINATION OF DEXAMETHASONE IN TEARS BY CAPILLARY ELECTROPHORESIS

selective capillary zone electrophoresis (CZE) microassay was develope d for the simultaneous determination of dexamethasone phosphate and it s major metabolite, dexamethasone, in tears. The calibration was carri ed out in the biological matrix with indoprofen as an internal standar d which allowed the separation of dexamethasone phosphate and dexameth asone from the tear constituents. The limits of detection and quantifi cation of the assay were 0.5 and 2.0 mu g ml(-1), respectively. This q uantification method is essential for the in vivo determination of dex amethasone concentration-time profiles in tears after application of t he antiinflammatory drug.