Rapid electrochemical chemosensor for acrylamide detection in drinking water

Overview

Acrylamide is a probable human carcinogen that can form in drinking water and certain foods during high-temperature processing. Regulatory bodies have established stringent maximum allowable concentrations, making sensitive and rapid detection essential for water safety monitoring. This offering presents an electrochemical chemosensor platform designed for the rapid, simple, and cost-effective analysis of acrylamide in drinking water.

The core innovation is a gold electrode modified with gold nanoparticles (AuNPs) and dithiothreitol (DTT), which together create a high-surface-area sensing interface capable of selectively binding acrylamide. Detection is achieved through differential pulse voltammetry (DPV), enabling straightforward measurement without the need for complex laboratory instrumentation. The approach has already demonstrated a limit of detection (LOD) of 3.11 nM without any analyte enrichment, approaching the maximum allowable acrylamide concentration in drinking water of 2.8 nM.

Technical specifications

Key features:

• Gold electrode substrate enhanced with electrochemically deposited gold nanoparticles to increase surface area and enable self-assembly of the DTT recognition layer
• Dithiothreitol functionalization provides selective binding sites for acrylamide at the electrode surface
• Differential pulse voltammetry (DPV) enables direct, label-free electrochemical readout
• Impedance spectroscopy as a complementary detection mode with expected lower detection limits
• No requirement for sample pre-enrichment in the baseline configuration
• Future integration of preconcentration coatings such as carbowax/divinylbenzene (CW/DVB) for solid-phase microextraction directly on the electrode surface
• Exploration of soy protein isolate (SPI) coatings, leveraging hydrogen bonding, hydrophobic interactions, and van der Waals forces to capture acrylamide and further lower detection limits

Performance targets:

• Current LOD without enrichment: 3.11 nM
• Target LOD with surface enrichment: well below 0.2 µg/L regulatory threshold
• CW/DVB-coated fiber SPME with GC-MS reference method achieves 0.1 µg/L, indicating feasibility of similar performance on the electrochemical platform

Technology readiness level

The chemosensor fabrication and characterization have already been reported in a peer-reviewed publication (Nanomaterials 2021, 11, 2610), establishing proof-of-concept validation of the Au/AuNPs/DTT electrode design and DPV-based acrylamide detection. The current effort represents a continuing research program aimed at extending the platform's sensitivity through novel surface enrichment strategies. Planned validation includes impedance-based detection and the integration of CW/DVB and SPI coatings for on-electrode preconcentration, with the goal of achieving detection limits well below regulatory thresholds. The technology is at an early-to-mid stage of development, with demonstrated analytical performance and a clear pathway toward enhanced sensitivity suitable for routine water-quality monitoring applications.