Investigation of a high-efficiency nebulizer and a thimble glass frit nebulizer for elemental analysis of biological materials by inductively coupled plasma-atomic emission spectrometry

摘要

A high-efficiency nebulizer (HEN) and a demountable thimble glass frit nebulizer are evaluated for argon inductively coupled plasma-atomic emission spectrometry (Ar ICP-AES). Aerosol characteristics for the HEN and the thimble frit are studied using laser Fraunhofer diffraction. Analyte transport efficiencies, mass transport rates, detection limits, and short- and long-term stabilities are measured. Four standard reference materials (trace elements- in water, oyster tissue, bovine liver, and orchardleaves) are analyzed. For comparison, results obtained by a high-solid pneumatic nebulizer (conespray nebulizer) are also presented. Transport efficiencies of up to 50-60% are obtained for the HEN and the thimble frit nebulizer at an uptake rate of 11 mul min~(-1). For the elements tested, short- and long-term precisions and detection limits obtained with the thimble frit are comparable to those of a commonly used pneumatic nebulizer. Good agreement with certified values is obtained for six trace elements in a standard reference material (SRM) water sample nebulized by the thimble frit. However, signal suppression is observed when the biological or plant SRMs are nebulized with the thimble frit nebulizer. In contrast, satisfactory results are obtainedfor the same matrices when the HEN and the conespray nebulizer are used.