Having demonstrated its feasibility and applicability in Phase I, we propose to construct and support the evaluation of an analytical instrument. The instrument will have the following capabilities based on a combination of series coulometric sensors and liquid chromatography: Single sample analysis of up to 500 components in the 20 fg to 100 ng range in directly injected biological samples. Data reduction, compaction, storage and retrieval. Rapid second-to-minute single component analysis of electroactive drugs and biochemicals. The research plan is: - To complete the basic programming of the production prototype computer based system designed and constructed in Phase I. - To utilize the system in an iterative process of method evaluation designed to optimize the sequencing of writing of additional programs required to make the device generally useable. - To describe general method development rules, and validate two definitive application specific methods. - To utilize the experience with the production prototype to build and support four systems for external evaluations by organizations with both analytical and technical expertise and applications and program requirements to which the instrument capabilities are relevant. - To utilize the feedback from evaluation in the design of production instruments for a Phase III marketing effort.