Improvement of Metals and Phosphorus Analysis in Water Samples by Inductively Coupled Plasma Optical Emission Spectroscopy, Radio Frequency Power, and Nebulizer Gas Flow Rate Modification

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Abstract

Inductively coupled plasma optical emission spectrometry (ICP‐OES) is a powerful tool for simultaneous multielement analysis. The objective of this study was to determine optimum ICP‐OES operational parameters for aluminum (Al), copper (Cu), iron (Fe), manganese (Mn), sodium (Na), phosphorus (P), and zinc (Zn) in natural water samples. Five radio‐frequency forward powers (RF powers) and four nebulizer gas flow rates were tested. Different RF power values and nebulizer gas flow rates were found to be ideal for each element. Performance was best for Al, Na, and P at 1400 W RF power, whereas the optimal nebulizer gas flow rate for Na, Fe, Zn, and Al was 1 L min⁻¹. The differences in RF power and nebulizer gas flow rates were found to be driven by changes in 1) element emission lines for different RF powers and 2) evaporation rates, mean diameter drop sizes, solvent loading, and analyte signal intensities for different nebulizer gas flow rates and analyte concentrations. Grouping the elements with similar parameters will avoid reading delays.

Keywords:

• Analyte concentration
• nebulizer gas flow rate
• RF power

Notes

Mention of a trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the USDA and does not imply its approval to the exclusion of other products that may be suitable.