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This work presents an electrochemical sensor detecting a fungicide-azoxystrobin (AZO) in aqueous environments. This AZO sensor utilizes a thin-film metal electrode (TFME) combined with an AZO-selective molecularly imprinted polymer (AZO–MIP). The AZO–MIP was directly generated on TFME through electrochemical polymerization from the solution containing two functional monomers: aniline (Ani) and m-phenylenediamine (mPD), and the template: AZO, which was afterwards removed to form AZO-selective cavities in the polymer matrix. The AZO–MIP preparation was characterized by electrochemical and ellipsometry measurements. Optimization of the synthesis parameters, including the charge density applied during electrodeposition, the monomer-to-template ratio, was performed to enhance the sensor's performance. The results demonstrated that the AZO sensor achieved a low limit of detection (LOD) of 3.6 nM and a limit of quantification (LOQ) of 11.8 nM in tap water, indicating its sensitivity in a complex aqueous environment. The sensor also exhibited satisfactory selectivity for AZO in both ultrapure and tap-water samples and achieved a good recovery (94–119%) for the target analyte. This study highlights the potential of MIP-based electrochemical sensors for the rapid and accurate detection of fungicide contaminants in water, contributing to the advancement of analytical tools for water-quality monitoring and risk assessment. [ABSTRACT FROM AUTHOR]

This work demonstrates the determination of macrolide antibiotics in aqueous environments using a screen-printed electrode (SPE) combined with a molecularly imprinted polymer (MIP) prepared from dual functional monomers. By employing the reversible covalent interactions between diols of macrolide and boronic acids of 3-aminophenylboronic acid (APBA) as well as the noncovalent interactions between macrolide and m-phenylenediamine (mPD), a dual recognition involving the central macrocyclic lactone exclusive to all macrolides was successfully achieved, thus permitting the possible broad recognition of individual members of the class. The prepared macrolide MIP (mMIP) was characterised by electrochemical and ellipsometric measurements. Following optimization, the sensor demonstrated about four times better recognition for macrolides, including erythromycin (Ery), clarithromycin (Cla), and azithromycin (Azi), than its non-imprinted reference. In addition, low analytical limits were achieved (LOD 1.1–1.6 nM and LOQ 3.8–5.3 nM). Moreover, an excellent selectivity was displayed towards the macrolides in both buffer and tap water samples, and a good recovery (93–108%) of the analytes was achieved. The analytical approach described herein could be further developed as a portable sensing device capable of on-site monitoring of macrolides in environmental water. [Display omitted] • Electrochemical MIP sensor for nanomolar determination of macrolide antibiotics. • Synergy of covalent and noncovalent imprinting enables class-selective recognition. • Successful analysis of antibiotics in environmental water with good recovery. • Potential for rapid and on-site detection of environmental pollutants displayed. [ABSTRACT FROM AUTHOR]