Developing electrochemical PFAS sensors for soil analysis (CH, CT, ANT)

Developing PFAS sensors based on molecular imprinting polymers and advanced electrochemical sensing for on-site soil analysis.

Detecting per- and polyfluoroalkyl substances (PFAS) in soil is crucial for environmental monitoring due to their persistence and toxicity. Following RIVM (Dutch National Institute for Public Health and Environment), the background contamination of main PFAS contents in Dutch soil has been determined as, 1.4 µg/kg for PFOS and 1.9 µg/kg for PFOA (RIVM, 2020). Quickly determining the contamination level for a specific plot is demanding in practice to evaluate the potential risk. Currently the analysis of PFAS needs laboratory instruments, like chromatography or mass spectrometry that are expensive and unsuitable for on-site analysis. Electrochemical sensing, combined with molecularly imprinted polymers (MIPs), offers a promising alternative for creating cost-effective and portable detection platforms.

In this project, a PFAS sensor will be developed based on MIP-coated electrodes, targeting the detection of a few species of PFAS. We will employ screen-printed electrodes, using o-phenylenediamine (o-PD) as the monomers to electro-polymerize desired MIP layer on the electrode. The approach builds on recent advancements in MIP-based PFAS sensing and we will adapt it for soil analysis (1. ACS Sensors 3.7 (2018): 1291-1298; 2. Environmental Science & Technology Letters 7.7 (2020): 489-495). The MIP layer creates selective recognition sites for PFAS molecules. As shown in the figure, PFAS molecules binding to the MIP cavities reduces the electric current of the redox mediator(Ferrocene noted as “Fc” in the schematic). The project aims to establish a “proof-of-principle” demonstrator for a PFAS sensor. Building a clear correlation between PFAS concentrations and electrochemical signals will be the main task. Characterization of the sensor will involve multiple analytical techniques such as profilometry, IR (infrared) spectrometry and scanning electron microscopy (SEM) etc.

You will assist in electrode preparation, MIP synthesis, and electrochemical measurement on Saxion homemade platform. The work includes determining suitable electrochemical electrodes to improve the reliability and reproducibility. Working in a multidisciplinary team, you will study the electrochemistry, related measurement methods and master the MIP synthesis. In addition, you will master chemistry analysis skills for studying functional nano-materials.

Project duration:
Spring 24/25

Educational Programs:
– Chemistry (CH)
– Chemical Technology (CT)
– Applied Nanotechnology (ANT)

The position is open for:
– Internship
– Graduation project

Interested? please send your motivation letter and CV before the 1st of Feb. 2025 to Bert Swennenhuis, b.h.g.swennenhuis@saxion.nl or Xiaojun Yang, x.yang@saxion.nl