Ru Nanozyme-Loaded Fluorinated Strong-Base Anion-Exchange Resin for Dual-Mode Optical Screening of Per- and
Jiali Huang1, Qikun Zhou2, Ke Hu1
1State Key Laboratory for Quality and Safety of Agro-Products, Institute of Quality Standards and Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing100081, P. R. China.
ACS Applied Materials & Interfaces
|August 13, 2026
Summary
A novel Ru nanozyme-based resin efficiently detects perfluorooctanoic acid (PFOA) in water and milk using dual optical modes. This portable method offers sensitive screening for per- and polyfluoroalkyl substances (PFAS) in environmental and food safety applications.
Area of Science:
- Environmental Chemistry
- Analytical Chemistry
- Materials Science
Background:
- Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants impacting water and food safety.
- Existing detection methods for PFAS are often complex and not readily portable.
- There is a critical need for simple, rapid, and field-deployable screening tools for PFAS.
Purpose of the Study:
- To develop a novel dual-mode optical sensor for the sensitive detection of perfluorooctanoic acid (PFOA).
- To create a portable screening method for PFAS in environmental and food samples.
- To investigate the mechanism of PFOA enrichment and detection using a functionalized nanozyme resin.
Main Methods:
- Fabrication of a ruthenium (Ru) nanozyme-loaded per-fluoropolyether (PFPE)-containing strong-base ion-exchange (IEX) resin (PFPE-IEX+@Ru).
- Dual-mode optical sensing utilizing colorimetric changes in 3,3',5,5'-tetramethylbenzidine (TMB) oxidation and fluorescence emission.
- Characterization using X-ray photoelectron spectroscopy (XPS), zeta-potential analysis, and density functional theory (DFT) calculations.
- Development of a smartphone-based RGB analysis program for portable detection.
Main Results:
- The PFPE-IEX+@Ru resin effectively enriched PFOA via electrostatic and fluorous/hydrophobic interactions.
- PFOA adsorption suppressed Ru-catalyzed TMB oxidation, resulting in decreased absorbance (652 nm) and increased fluorescence (405 nm).
- Achieved detection limits of 0.50 μg L-1 (colorimetric) and 0.19 μg L-1 (fluorescence).
- Demonstrated acceptable recoveries in spiked water and milk samples.
- Showed concentration-dependent responses for other PFAS like PFOS and PFBA, indicating broader applicability.
Conclusions:
- The developed PFPE-IEX+@Ru sensor enables sensitive and dual-mode optical detection of PFOA.
- The smartphone-based system offers a portable solution for rapid PFAS screening.
- The method shows promise for on-site monitoring of PFAS in complex matrices.
- Further development is needed to address quantitative analysis of mixed PFAS congeners.
