Automated Agitation-Assisted Demulsification Dispersive Liquid-Liquid Microextraction.

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Dispersive liquid-liquid microextraction (DLLME) offers speed and efficiency for sample preparation.
• Full automation of DLLME is crucial for maximizing its analytical potential and applicability.

Purpose of the Study:

• To develop and validate a fully automated agitation-assisted demulsification-DLLME (AAD-DLLME) method.
• To integrate AAD-DLLME with gas chromatography/mass spectrometry for polycyclic aromatic hydrocarbon (PAH) determination in environmental water samples.

Main Methods:

• Utilized a multipurpose autosampler with dual microsyringes for automated liquid handling and sample injection.
• Implemented agitation post-extraction for efficient demulsification, eliminating the need for centrifugation or demulsification solvents.
• Employed a low-density solvent as the extractant for simplified upper-layer extract collection.

Main Results:

• Achieved good linearity across a wide concentration range (0.1-0.5 μg/L to 50 μg/L).
• Demonstrated low limits of detection (0.010-0.058 μg/L) and excellent repeatability (RSD < 5.3%).
• Successfully applied the method to analyze PAHs in real river water samples.

Conclusions:

• The automated AAD-DLLME method provides a convenient, efficient, and flexible approach for PAH analysis.
• This automation significantly reduces manual labor, time, and resource requirements.
• The developed method enhances the accessibility and practicality of DLLME for environmental monitoring.