Characterization of Near-Infrared Atomic Emission from a Radio-Frequency Plasma for Selective Detection in Capillary Gas Chromatography

Abstract

A radio-frequency plasma source has been characterized for use as an element-selective detector with capillary gas chromatography using atomic emission in the near-infrared region of the spectrum. With selected compounds introduced at rates similar to those encountered during a chromatographic run, the performance of the plasma has been characterized as a function of several interdependent variables, including plasma makeup gas flow, electrode spacing, and applied power. These settings have been optimized, and detection limits for several nonmetallic elements determined. Detection limits range from 0.2 to 50 pg/s.