Characterization of a High-Efficiency Helium Microwave-Induced Plasma as an Atomization Source for Atomic Spectrometric Analysis

Abstract

Characterization studies of a He high-efficiency microwave-induced plasma, He-HEMIP, utilizing direct sample introduction with pneumatic nebulization for atomic emission and atomic fluorescence spectrometry are presented. These studies include diagnostic measurements and analytical characterization of the 150-W He-HEMIP. Diagnostic measurements include excitation temperatures with the use of aqueous and organic nebulized thermometric species, electron number densities, and ionization temperatures for the plasma. The effect of sample uptake rate on the emission intensity is investigated. Ionization interferences are minimal, and phosphate interferences were found not to occur. In addition, the He-HEMIP is characterized as an atom source for metals and nonmetals with the use of atomic emission spectrometry and atomic fluorescence spectrometry. With AES, detection limits for metals and nonmetals are in the sub-ppm range. With AFS, detection limits for metals were determined to be in the low to sub-ppb range and were found to be not statistically different from those reported for HCL-ICP-AFS. Linear ranges for AES and AFS ranged from four up to five and one-half orders of concentrative magnitude.

Characterisation of a Microwave-induced Plasma Atomic Emission Spectrometry System Using a Modified Plasma Torch Coupled With Pneumatic and Hydraulic High-pressure Nebulization

“…Generator Several attempts to use the MIP for the analysis of aqueous A microwave generator with a working frequency of 2450 MHz aerosols have been reported. 4,8,9,12,[17][18][19]26,[28][29][30][31][32][33][34][35][36][37][38] To date, a was used. The power supply provides a maximum power of serious problem has been the ineÃcient introduction of the 800 W. The maximum power could be used only in short-term aerosols into the plasma zone, since in contrast to the ICP mode because of overheating problems.…”

A low-flow low-power helium microwave induced plasma for optical and mass spectrometry with solution nebulization

“…Plasma robustness of the new helium MIP is also observed for Cl and Br ionic lines compared to the results obtained by Perkins and Long. 17 Obviously, those detection limits are higher compared to data from Okamoto and Okamoto, 16 who used a high power MIP system. In addition, an aerosol desolvation was employed.…”

“…The DLs are compared with our previous results obtained with HeMIP 12 and ArMIP 14 by TE 101 resonant cavity as well as for various helium and argon MIPs used by others. [15][16][17][18] The present helium MIP system provides limits of detection between 12 and 70 ng ml À1 for metals and metalloids. The relative standard deviation of the background as well as of the signals was typically below 2% owing to the high plasma stability.…”

Evaluation of figures of merit for Zn determination in environmental and biological samples using EDL excited AFS in a new radiofrequency capacitively coupled plasma

“…[7][8][9] Another highly sensitive and selective analytical technique for Zn determination is fluorescence atomic spectrometry (AFS) with or without hydride generation and different atomization cells (argon-hydrogen flame, ICP, microwave induced plasma-MIP, microwave plasma torch-MPT). 2,[10][11][12][13][14][15] Atomic emission spectrometry using different radiofrequency capacitively coupled plasma sources (r.f.CCP-AES) was proposed as an alternative to ICP-AES because of the advantages related to versatility of the geometry operation, low Ar(He) consumption (<1 L min À1 ), low power operation level (<300 W), similar analytical performance for easily volatile and excitable elements and torch miniaturisation. [16][17][18][19][20][21][22][23] In our laboratory a r.f.CCP torch with single or double ring electrode (SRTr.f.CCP or DRTr.f.CCP) placed outside a quartz tube has been developed during the last 10 years as multielemental source for atomic emission spectrometry with the advantage of high stability of plasma for pneumatic nebulization without desolvation.…”