Design and testing of a low-cost multichannel pseudopotentiostat for quantitative combinatorial electrochemical measurements on large electrode arrays

We describe a simple multichannel pseudopotentiostat based on appropriately chosen resistors, a programmable voltage source, and a scanning multimeter. Our first pseudopotentiostat can perform cyclic voltammetry on 64 channels of a combinatorial electrochemical cell that has 64 working electrodes and common counter and reference electrodes. The performance of the pseudopotentiostat and a 100 channel Scribner model 900B multichannel microelectrode analyzer (MMA) are compared on the same channels of the same cell. We find that for experiments on arrays of lithium-insertion electrodes, the pseudopotentiostat provides equivalent information to the MMA at about 20% the cost. The cost benefits are more significant as the number of channels increases so we believe this represents a good strategy for measurement systems to be used in quantitative combinatorial electrochemistry studies of large arrays. (C) 2003 The Electrochemical Society.