On-line electrogenerated Ru(bpy)33+ chemiluminescent detection of β-blockers separated with capillary electrophoresis

A novel chemiluminescence (CL) detection scheme for capillary electrophoresis (CE) has been developed based on the Ru(bpy)33+ CL reaction. Ru(bpy)32+ is incorporated into the CE electrolyte and an electrode inserted into the outlet end of the capillary electrochemically oxidizes the Ru(bpy)32+ into the active Ru(bpy)33+ form, which then reacts with analytes at the end of the CE column and produces light. The performance of the system is characterized for a series of β-blockers, with an LOD for oxprenolol of 0.6 μg mL−1 and a separation efficiency of 15 000.