Solid Sampling in Analysis of Various Plants Using Two-Jet Plasma Atomic Emission Spectrometry

Area of Science:

• Analytical Chemistry
• Environmental Science
• Plant Science

Background:

• Accurate elemental analysis of diverse plant matrices is crucial for environmental and agricultural monitoring.
• Traditional methods often require complex sample preparation and may not be suitable for all plant types.

Purpose of the Study:

• To investigate the efficacy of two-jet plasma atomic emission spectrometry for analyzing trace elements in various plant samples.
• To develop a unified approach for solid sample preparation and calibration applicable to different plant matrices.
• To optimize sample preparation techniques, including carbonization, for enhanced analytical sensitivity and accuracy.

Main Methods:

• Utilized certified reference materials of wheat, maize, rice, potato, grass mix, birch leaves, and Elodea canadensis.
• Classified plants into starch-containing (cereal/root crops) and leaves/grass groups based on plasma behavior.
• Employed direct analysis for leaves/grass and pre-sample carbonization for starch-containing plants and low-concentration analysis.
• Developed a calibration method using graphite powder and a spectroscopic buffer for both direct and carbonized samples.

Main Results:

• Successfully estimated concentrations of B, Ba, Be, Cd, Co, Cr, Cu, Ga, Fe, Mn, Ni, Pb, Si, Sr, V, and Zn in various plant types.
• Achieved low limits of detection (LODs), with direct analysis LODs at n×0.1 µg·g⁻¹ for Cd, Cu, Mn, and n×10 µg·g⁻¹ for Si.
• Carbonization significantly improved LODs, reaching n×0.01 µg·g⁻¹ for Be, Cd, Cu, Mn, and n×0.1 µg·g⁻¹ for several other elements.
• The developed techniques are rapid, simple, and do not require hazardous chemical reagents.

Conclusions:

• The two-jet plasma atomic emission spectrometry method, with optimized sample preparation (carbonization or direct analysis), provides a robust and efficient means for trace element determination in diverse plant species.
• The unified calibration approach simplifies analysis across different matrices.
• While generally effective, potential matrix effects and varying element species require consideration for complete accuracy, warranting further investigation.