A continuous flow polyurethane foam solid phase microextraction lab-in-syringe platform for the automatic...

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Flame atomic absorption spectrometry (FAAS) is a common technique for metal determination.
• Traditional methods often require extensive sample preparation and can be time-consuming.
• Developing automated and efficient preconcentration techniques is crucial for trace metal analysis.

Purpose of the Study:

• To develop a fully automatic continuous flow polyurethane foam solid phase microextraction lab-in-syringe system.
• To integrate this system as a front-end for flame atomic absorption spectrometry (FAAS).
• To enable on-line sample preconcentration and separation for toxic metal determination.

Main Methods:

• A novel lab-in-syringe system utilizing polyurethane foam was designed for continuous flow microextraction.
• On-line metal complexation with ammonium pyrrolidine dithiocarbamate was performed.
• Elution was achieved using methyl isobutyl ketone (MIBK).
• Optimization of chemical and hydrodynamic parameters was conducted using Cadmium (Cd) and Lead (Pb) as model analytes.

Main Results:

• The system achieved low limits of detection (0.20 μg L⁻¹ for Cd, 1.7 μg L⁻¹ for Pb) with a 90-second preconcentration time.
• Significant enhancement factors were observed (79 for Cd, 150 for Pb).
• Relative standard deviations were below 2.8%, indicating high precision.
• Successful application to environmental water analysis yielded high relative recoveries (94.0–104.4%).

Conclusions:

• The developed continuous flow lab-in-syringe system offers a highly efficient and automated approach for toxic metal determination.
• The method demonstrates reduced environmental impact and high practicality, suitable for routine environmental monitoring.
• This novel system represents a significant advancement in on-line sample preconcentration for trace metal analysis using FAAS.