Electrothermal vaporization inductively coupled plasma mass spectrometry for determination of vanadium and chromium in soils

Ultrasonic slurry sampling electrothermal vaporization dynamic reaction cell™ inductively coupled plasma mass spectrometry (USS-ETV-DRC-ICP-MS) was applied to determine of V and Cr in several soil samples. The influences of instrument operating conditions and slurry preparation on the ion signals were investigated. Ascorbic acid was used as the modifier to enhance the ion signals. In order to save experiment time, an ultrasonic nebulizer was used for the selection of dynamic reaction cell (DRC) operating conditions. The background ions at the vanadium and chromium masses were significantly reduced in intensity by using NH3 as reaction cell gas in the DRC. Standard addition method was used for the determination of V and Cr in these soil samples. This method has been applied to the determination of V and Cr in NIST SRM 2711 Montana soil and NIST SRM 2709 San Joaquin soil reference materials and a soil sample collected from the Kaohsiung area. The analysis results of the reference samples agreed with the certified values. The precision between sample replicates was better than 3% with the USS-ETV-DRC-ICP-MS method. The method detection limits estimated from standard addition curves were approximately 0.24 and 0.16 μg g−1 for V and Cr, respectively, in the original soil sample.