Trace-level mercury ion (Hg2+) analysis in aqueous sample based on solid-phase extraction followed by microfluidic...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Biotechnology

Background:

• Mercury (Hg(2+)) is a significant heavy-metal pollutant due to its bioaccumulation and toxicity.
• Effective monitoring of Hg(2+) contamination necessitates high-throughput, cost-effective analytical methods for environmental samples.

Purpose of the Study:

• To develop a simple, sensitive, and rapid analytical method for detecting Hg(2+) in environmental aqueous samples.
• To integrate a microfluidic immunoassay with solid-phase extraction (SPE) for enhanced mercury detection.

Main Methods:

• Development of an ultrasensitive microfluidic immunoassay for Hg(2+) with a 10-minute assay time and a 0.13 μg/L limit of detection (LOD).
• Creation of an ion-exchange resin (IER)-based SPE method for selective Hg(2+) extraction from complex aqueous matrices.
• Combined SPE and microfluidic immunoassay approach for analyzing real-world water samples.

Main Results:

• The integrated SPE-microfluidic immunoassay achieved an LOD of 0.83 μg/L for Hg(2+).
• This detection limit meets or exceeds guidelines set by the United States Environmental Protection Agency (USEPA) and the World Health Organisation (WHO).
• The method demonstrated accurate analysis of spiked tap, mineral, and river water samples, with results comparable to traditional atomic adsorption spectroscopy.

Conclusions:

• The developed SPE-microfluidic immunoassay is a robust and efficient tool for monitoring Hg(2+) contamination in environmental water.
• This method provides a high-throughput, cost-effective solution for screening large numbers of samples, aiding in environmental protection efforts.