Electrochemically pretreated graphite:glass thick films for ultra-trace detection of neonicotinoids in surface water and honey

Dekleva, Maksimiljan (author), Repič, Barbara (author), Kuščer, Danjela (author), Tasić, Nikola (author), Kolar, Mitja (author), Prosen, Helena (author), Marolt, Gregor (author)

Neonicotinoids (NNIs) pose a significant threat to pollinator populations and environmental health due to their widespread use and adverse effects on non-target organisms. Despite regulatory efforts, monitoring of NNIs in natural ecosystems remains challenging. In contrast to conventional chromatographic methods, integrated electrochemical sensors provide a rapid and on-site detection of NNIs. In this study, we report on a novel voltammetric sensor based on the electrochemical pretreatment of an in-house screen-printed graphite:glass electrode for a sensitive and selective detection of clothianidin (CLO), imidacloprid (IMI), and thiamethoxam (TMX). Electrochemical characterization via cyclic voltammetry and impedance spectroscopy demonstrated a significant enhancement in electrode performance after the pretreatment, offering strong adsorption properties and detection limits in the nanomolar level, achieving the lowest reported LODs for CLO (26 nmol L$^{−1}$) and IMI (12 nmol L$^{−1}$). For all three NNIs, two linear ranges between 0.5 and 40 μmol L$^{−1}$ were observed, alongside great sensitivity (8.1–13.1 μA μmol$^{−1}$ L, depending on the analyte). Notably, the recoveries obtained for NNIs in surface water and honey samples, ranging from 96.3 % to 107.8 %, indicate its applicability for real-sample and on-field monitoring. Utilizing one-step voltammetric electrode pretreatment and adsorption-based pre-concentration offers a cost-effective, fast, and ultra-sensitive platform, thus addressing a critical need in environmental analysis and pesticide regulation.

• Language: English
• Keywords: screen-printed electrode, voltammetric sensor, neonicotinoids, environmental monitoring, surface water, honey
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 10 str.
• Numbering: Vol. 50, art. 100890
• PID: 20.500.12556/RUL-174667
• UDC: 543.552:661.16
• ISSN on article: 2214-1804
• DOI: 10.1016/j.sbsr.2025.100890
• COBISS.SI-ID: 252228611
• Publication date in RUL: 08.10.2025

Record is a part of a journal

• Title: Sensing and bio-sensing research
• Publisher: Elsevier
• ISSN: 2214-1804
• COBISS.SI-ID: 520394521

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: sitotiskana elektroda, voltametrični senzor, neonikotinoidi, okoljski monitoring, površinska voda, med