Zwitterion-functionalized polymer microspheres-based solid phase extraction method on-line combined with HPLC-ICP-MS...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Mercury contamination in water poses significant environmental and health risks.
• Accurate speciation of mercury is crucial for risk assessment and environmental monitoring.
• Existing methods for mercury speciation often require complex procedures and lack sensitivity.

Purpose of the Study:

• To develop a novel zwitterion-functionalized polymer microsphere (ZPM) adsorbent.
• To establish an on-line solid-phase extraction (SPE) method for selective mercury enrichment.
• To achieve sensitive and accurate speciation of inorganic and organic mercury species in environmental waters.

Main Methods:

• Preparation of zwitterionic S-ZPMs and N-ZPMs from Merrifield resin.
• On-line solid-phase extraction (SPE) using a mini-column packed with ZPMs.
• Mercury species separation and detection via High-Performance Liquid Chromatography coupled with Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS).

Main Results:

• Quantitative adsorption of inorganic mercury (In-Hg), methylmercury (MeHg), and ethylmercury (EtHg) by ZPMs.
• Achieved high enrichment factors (up to 105 for In-Hg, 98 for organic mercury) with 40 mL sample volume.
• Obtained low detection limits (0.49–0.78 ng/L) and good precision (RSD < 4.1%) for mercury species.

Conclusions:

• The developed ZPMs are effective adsorbents for selective and rapid mercury enrichment.
• The on-line SPE-HPLC-ICP-MS method offers a sensitive, selective, and facile approach for mercury speciation.
• The method's feasibility and accuracy were validated in real environmental water samples.