P-082

Pamela Rivera

pamela.rivera@ftmc.lt

Aswad Munir, Justina Stonytė, Rasa Pauliukaitė

Department of Nanoengineering, Center for Physical Sciences and Technology (FTMC), Lithuania

Electropolymerized Polydopamine Films for Enhanced Electrochemical Detection of Heavy Metals

Heavy metals (HMs) are persistent environmental pollutants that bioaccumulate in the body, causing cellular damage and leading to severe health issues, including cancer, immune deficiencies, and developmental disorders [1], [2]. Produce consumption is a major exposure route, making agricultural monitoring crucial to mitigate contamination risks in the food chain. Electrochemical sensors offer a sensitive, portable, and robust platform for HM detection, yet challenges in sensing material fabrication hinder their scalability and reproducibility, limiting their widespread adoption in routine analysis.

Polydopamine (PDA) is a bioinspired polymer that mimics the adhesive and metal-binding properties of mussel proteins [3]. This makes it an ideal candidate for enhancing metal ion adsorption at electrode interfaces. Its catechol and amine functional groups facilitate strong chelation with metal ions, improving preconcentration and sensor response [3], [4]. Additionally, PDA enhances surface hydrophilicity, reducing electrode fouling and improving sensors’ stability.

To evaluate the impact of PDA modification, films are electropolymerized onto conductive electrode surfaces (screen printed electrodes) via cyclic voltammetry. Optimization of deposition parameters such as polymerization time, potential range, and dopamine concentration, enables precise control over film morphology and electrochemical properties. The modified electrodes are characterized using atomic force microscopy (AFM) for surface topography, infrared spectroscopy (IR) for functional group analysis, and electrochemical impedance spectroscopy (EIS) for charge transfer resistance evaluation.

The electrochemical performance of PDA-modified electrodes is  tested for Zn²⁺, Cd²⁺, and Pb²⁺ detection using square wave anodic stripping voltammetry (SWASV). This study examines how variations in polymerization conditions affect metal ion preconcentration, selectivity, and electrochemical response in the presence of common interfering ions. Additionally, sensor stability and reproducibility will be assessed over multiple measurement cycles.

References

[1] A. Alengebawy et al., Toxics, vol. 9, no. 3, 2021, doi: 10.3390/toxics9030042.

[2] D. Witkowska et al., Molecules, vol. 26, no. 19, p. 6060, 2021, doi: 10.3390/molecules26196060.

[3] S. Li et al., Mater. Adv., vol. 2, no. 7, pp. 2216–2230, 2021, doi: 10.1039/D1MA00053E.

[4] Y. H. Ding et al., Biosurf. Biotribol., vol. 2, no. 4, pp. 121–136, 2016, doi: 10.1016/j.bsbt.2016.11.001.