Mass Spectrometric and Contactless Conductivity Detection Approaches in the Determination of Muscle Relaxants by Capillary Electrophoresis
Abstract
Novel and rapid capillary electrophoresis-coupled tandem mass spectrometry (CE-MS/MS) and capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C(4)D) methods have been developed for the separation and determination of three neuromuscular blocking agents: pancuronium, vecuronium, and rocuronium. In both cases, the separation was conducted in background electrolytes based on acidic acetate-ammonium buffers to avoid possible decomposition of the analytes that are known to be unstable in alkaline media.
Baseline resolution of the analytes was achieved in the presence of modified gamma-cyclodextrin by CE with C(4)D detection. The two detection techniques were compared with regard to analytical figures of merit including linear dynamic range, limit of detection, limit of quantification, precision, and accuracy.
The calibration curves showed good linearity for both detection methods examined (characterized by r(2) >= 0.9908). The LODs of the CE-MS/MS and the CE-C(4)D methods differed at least by two orders of magnitude considering all analytes.
The differences in precision and accuracy of these methods were evaluated and discussed. The assays of pancuronium, vecuronium, and rocuronium in commercial injection solutions by CE-MS/MS and CE-C(4)D were performed and the results compared.