Hydride Preconcentration for Inductively Coupled Plasma Optical Emission Spectrometry

Abstract

Studies are presented describing an improved application of the NaBH4 reduction of soluble arsenite to form arsine as a preconcentration approach for ultra-trace level arsenic determination by inductively coupled plasma optical emission spectrometry. Specialized analyte introduction techniques are described for elimination of reaction by-products that would normally extinguish a medium power plasma discharge. An approach is presented to minimize the need for background correction and facilitate a superior arsenic detection limit (≤0.03 ng/ml) in a relatively inexpensive 1.2 kW inductively coupled plasma system.

A hydride generator system for a 1-kW inductively coupled plasma

“…1930, 20, 701-718. (18) Geary, J. C.; Kent, S. M. INTRODUCTION There are several valuable analytical characteristics that make inductively coupled plasma atomic emission spectroscopy (ICP-AES) a widely utilized atomic emission technique for single and multielement major, minor, and trace analysis. These include low detection limits for a large number of elements, calibrations that are linear over a very wide range (generally 5 to 6 orders of magnitude), low matrix or chemical interference effects, fast operation, and multielement determination capability (1)(2)(3)(4)(5)(6)(7)(8).…”

Plasma optical emission and mass spectrometry

“…Due to the small droplet size, aerosol generation efficiencies of up to 30% are possible and thus increased sensitivities as compared to pneumatic nebulization can be expected. In the case of weak plasmas such as the MIP, the excess of hydrogen must mostly be removed and an isolation of the hydrides by freezing them out and a subsequent sweeping into the plasma may solve the problem, as it was already described by Fry et al [66] for the case of the ICP. Further, memory effects occur and accordingly, the clean-up times a e long.…”

Ultra-sensitive, simultaneous determination of arsenic, selenium, tin, and antimony in aqueous solution by hydride generation gas chromatography with photoionization detection

“…Of the four systems that did not employ a drying agent prior to the trap, two employed a tube of NaOH pellets after the trap to remove C02, which otherwise interfered with the emission discharge tube response to arsine. Selenium hydride could not be determined with these two systems, because it is removed from the gas stream by NaOH pellets (7,8). Carbon dioxide scrubbing is also sometimes performed prior to the cold trap to avoid clogging it with dry ice when residual carbonates are acidified and degassed from solutions as C02 (9,10).…”