FLOW INJECTION ANALYSIS WITH RETICULATED VITREOUS CARBON FLOW-THROUGH ELECTRODES

The Reticulated Vitreous Carbon flow-through electrode is demonstrated to be a useful detector for flow injection analysis in both an amperometric and a coulometric mode of operation. A relative precision of a few ppt was achieved in the latter mode, but the sampling rate was limited to about 24 samples per hour. A liquid chromatographic internal sampling valve was used to inject the sample into the supporting electrolyte stream. With amperometric operation, sampling rates as high as 264 samples per hour were achieved with a relative precision of ±0.5%. A peak current detector is described which stores the peak current in a 10-bit A/D converter. The reduction of ferricyanide ion and the oxidation of ascorbic acid, epinephrine, and L-Dopa were investigated. Detection limits for these analytes are a few tenths of a nanogram. © 1979, American Chemical Society. All rights reserved.