Flow-injection analysis with chemiluminescence detection.
Abstract In "flow-injection analysis," the sample is inserted into a stream of reagent by use of a sample-injection valve. Mixing occurs downstream from the valve in a coil of tubing. With chemiluminescence detection this coil is positioned in front of a photomultiplier. We have evaluated the system for detection of hydrogen peroxide, using the luminol reaction with cupric ion as a catalyst. The effects of flow rate, sample volume, and reaction kinetics on the magnitude, duration, and repeatability of the chemiluminescent response have been evaluated. Precisions of 1 to 2% relative standard deviation on replicate measurements are readily achievable. A sample throughput of six samples per minute is possible with very little peak overlap. This detection system can be coupled to any process in which peroxide is generated.