The computer aided design and experimental development of a new device forthe measurement of electrochemiluminescence

A new hydrodynamic technique is presented which provides quantitative spati al resolution of electrogenerated chemiluminescence (ECL) under steady stat e voltammetric operating conditions. Specifically a channel flow cell arran gement was employed exploiting a double electrode configuration. The two el ectrodes were utilized to electrogenerate different reactants separately an d the solution velocity exploited to bring the generated reactants together The ECL spectra were recorded using a charge coupled device (CCD) which pe rmits the full spectrum to be measured in intervals of approximately 10 ms. Alternatively the CCD permits the variation of intensity to be recorded as a function of the cell position and this was also exploited within these i nvestigations. The cell configuration and volume flow rate range were optim ized for maximum ECL detection sensitivity using a computer aided design st rategy. This was achieved by the use of a finite difference model which pre dicts the concentration profiles within the channel cell for a range of ele ctrode arrangements. The validity of the new strategy is evaluated by exper imental studies utilizing the well documented 9,10-diphenylanthracene (DPA) system. The variation of ECL intensity as a function of the volume flow ra te permits kinetic and mechanistic data to be derived via comparison with a ppropriate numerical modeling for candidate mechanisms. Good agreement is o btained between theory and experimental measurements.