Determination of Cr, Cu, Ni and Zn in Soils Using Fast Sequential Mode

Importance of Topic

Soil contamination with heavy metals poses serious environmental and health risks. Reliable, high-throughput methods are essential for monitoring Cr, Cu, Ni and Zn concentrations in various soil matrices. Conventional flame AAS is limited by single-element aspiration, leading to lengthy analysis times and increased resource consumption.

Objectives and Overview of Study

This study evaluates the performance of the Agilent 240FS fast sequential flame atomic absorption spectrometer for simultaneous determination of Cr, Cu, Ni and Zn in certified reference soil samples. The key aims were to assess analytical accuracy, efficiency gains and operational cost reductions compared to conventional AAS methods.

Methodology and Instrumentation

The FS mode enables sequential measurement of all four elements within a single aspiration cycle, reducing the need for repeated sample uptake. Certified reference soils (GSS series) were analyzed to verify method accuracy. Operating conditions included lamp currents of 10 mA for all elements, wavelengths of 324.8 nm (Cu), 213.9 nm (Zn), 232.0 nm (Ni) and 357.9 nm (Cr), slit widths of 0.5 nm (Cu) and 0.2 nm (Zn, Ni, Cr), air–acetylene flame with acetylene flow at 2.0 L/min and air flow at 13.5 L/min.

Main Results and Discussion

Measured concentrations for Cr, Cu, Ni and Zn in all reference samples matched certified values within ±10%, demonstrating excellent accuracy. Fast sequential mode reduced total analysis time by approximately 50%, completing determination of four elements in eight samples in 15 minutes. Gas consumption was similarly reduced. The FS system’s rapid lamp selection and high-speed wavelength drive ensure optimal conditions for each element without manual intervention.

Benefits and Practical Applications

The fast sequential flame AAS approach offers:

• Significant time savings and increased sample throughput
• Lower acetylene and air consumption
• Reduced reagent and handling costs
• Automated multi-element analysis for routine soil testing and QA/QC labs

Future Trends and Opportunities

Advancements in AAS technology continue to focus on further automation, integration with sample preparation modules, and expansion to additional analytes. Coupling FS flame AAS with data management software and remote operation could streamline environmental monitoring programs and support large-scale soil survey initiatives.

Conclusion

The Agilent 240FS fast sequential flame AAS provides a robust, efficient solution for multi-element soil analysis. This method achieves high accuracy and substantial resource savings, making it well-suited for high-throughput environmental laboratories.

Reference

• Agilent Technologies, Inc. (2021) Application Brief: Determination of Cr, Cu, Ni and Zn in Soils Using Fast Sequential Mode