Rapid-scan hydrodynamic voltammetry and cyclic voltammetry of pharmaceuticals in flow injection analysis conditions

An on-line rapid-scan electrochemical detector is described for HPLC and FIA systems. Its practical use in qualitative analysis is demonstrated for 19 drug substances. The detector can be operated to record convection/diffusion-controlled (S-shaped), or diffusion-controlled (peak-shaped) voltammograms. In the latter mode, on-line cyclic voltammetry measurements are possible. The cell can also be used as an amperometric detector for conventional, microbore and micro-LC methods. Detection limits are of the order of 10 pg (conventional and microbore HPLC), or at the sub-picogram level (micro-LC). For scanning work, drugs can be analysed at mg l-1 levels in an FIA setup.