Simple, Affordable Distance-Based Paper Analytical Device for the Quantitative Perfluorooctane Sulfonate Detection in...

Area of Science:

• Analytical Chemistry
• Environmental Science
• Materials Science

Background:

• Global concern over per- and polyfluoroalkyl substances (PFAS) contamination in water and food necessitates simple, cost-effective monitoring methods.
• Perfluorooctanesulfonate (PFOS) is a prevalent and concerning PFAS compound requiring sensitive detection techniques.

Purpose of the Study:

• To develop and validate a novel distance-based paper analytical device (dPAD) for the sensitive and cost-effective detection of PFOS.
• To demonstrate the dPAD's utility in analyzing PFOS levels in consumable samples like drinking water and beverages.

Main Methods:

• Utilized silver nanoparticles (AgNPs) and hydrogen peroxide (H2O2) to generate hydroxyl radicals (•OH).
• Leveraged the oxidative decomposition of PFOS by •OH to reduce the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB).
• Quantified PFOS by measuring the change in uncolored distance length on the paper substrate, enhanced by hydrophobic wax lines in a delay channel.

Main Results:

• Achieved a linear detection range of 3.0-15.0 ng L−1 with R2 = 0.9972 and a limit of detection (LOD) of 3.0 ng L−1.
• Demonstrated high accuracy and precision in beverage and water samples, with recoveries between 95.0-107.5% and a maximum relative standard deviation (RSD) of 7.89%.
• Results showed strong correlation with high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) at a 95% confidence level.

Conclusions:

• The developed dPAD sensor is the first of its kind for PFOS detection, offering a promising, instrument-free approach for real-world applications.
• The dPAD method is significantly cheaper and easier to use than conventional techniques requiring expensive instrumentation and skilled operators.
• This technique enables rapid PFOS monitoring in water and beverages, crucial for assessing food quality in resource-limited settings and developing countries.