LAUSR

The authors developed a simple method to measure angiotensin-converting enzyme (ACE) activity using capillary electrophoresis (CE). With hippuryl-L-histidyl-L-leucine (HHL) as the substrate, we separated and quantified the enzymatic product, hippuric acid (HA) using capillary zone electrophoresis (CZE). CZE was performed with a 65 cm fused-silica capillary (55 cm effective length, 75 µm I.D.), using a 10 or 20 mM phosphate solution (pH 6.0) as the running buffer with an applied voltage of 20 kV at room temperature. The HA was identified and monitored at 228 nm.