COMPARATIVE-STUDY OF ARGON AND HELIUM PLASMAS IN A TM(010) CAVITY ANDA SURFATRON AND THEIR USE FOR HYDRIDE GENERATION MICROWAVE-INDUCED PLASMA ATOMIC EMISSION-SPECTROMETRY

Argon and helium microwave-induced plasmas (MIPs) operated in a TM010 Beenakker resonator and in a surfatron were investigated for the deter mination of hydride-forming elements. The MIPs in both devices were op timized with elemental mercury vapour. The analytical figures of merit were determined for As, Sb and Se in the case of hydride generation f ollowed by trapping in a hot graphite furnace and subsequent evaporiza tion of the analyte into the plasma. The long-term stability of the pl asmas obtained in both devices was found to be very good. With the sur fatron the absolute detection limits for the determination of As, Sb a nd Se (0.1-0.2 ng) were half those with the TM010 cavity.