DETERMINATION OF ORGANOMETALLIC AND INORGANIC GERMANIUM BY INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION-SPECTROMETRY

Organometallic and inorganic germanium in aqueous solutions are determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Sodium hydroxide solution is a suitable medium for the determination because of the stability of the analyte in the solution and the suppression of interference from halide ions. The germanium-carbon bonds of organogermanium compounds are so effectively broken in the plasma that monomethyl-, dimethyl-, monoethyl-, diethyl- and monophenylgermanium in alkaline solutions can be determined using the same calibration graph as that for inorganic germanium (Ge(i). Dilute hydrochloric acid is another promising medium for highly sensitive detection by ICP-AES, as the emission intensity for germanium compounds increases to 51-63 times that for Ge(i) in 0.1 M sodium hydroxide solution. Such an effect was not observed with nitric acid or sodium chloride. The enhancement of sensitivity is attributable to the improvement in the efficiency of introduction of the analyte into the plasma caused by the formation of volatile chlorides of germanium compounds.