RESEARCH ARTICLE Synthesis and application of ion-imprinted polymer for the determination of mercury II in water samples Janaina E. Francisco 1 & Fernanda N. Feiteira 1 & Wanderson A. da Silva 1,2 & Wagner F. Pacheco 1 Received: 16 November 2018 /Accepted: 12 April 2019 # Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract In this study, an innovative analytical methodology capable of selectively identifying and quantifying mercury contamination by the association of solid-phase extraction using ion-imprinted polymers as a sorbent phase and differential pulse anodic stripping voltammetry is proposed. To this end, the ion-imprinted polymers were synthesized and characterized by infrared spectroscopy and atomic force microscopy. The sorption capacities and the selectivity of the ion-imprinted polymers were compared to the ones related to the non-imprinted ones. Next, the experimental parameters of this solid-phase extraction method (IIP-SPE) were evaluated univariately. The selectivity of this polymeric matrix against other cations (Cd II, Pb II, and Cu II) was also evaluated. Limits of detection (LOD) and quantification (LOQ) obtained for the here proposed methodology were 0.322 μgL -1 and 1.08 μgL -1 , respectively. Also, the precision of 4.0% was achieved. The method was finally applied to three water samples from different sources: for the Piratininga and Itaipu Lagoon waters, Hg II concentrations were below the LOQ and for Vargem River waters a concentration equal to 1.35 ± 0.07 mg L -1 was determined. These results were confirmed by recovery tests, resulting in a recovery of 96.2 ± 4.0%, and by comparison with flame atomic absorption spectrometry, resulting in statistical conformity between the two methods at 95% confidence level. Keywords Ion-imprinted polymer . SPE . Mercury . Voltammetry Introduction Due to population growth and the development of the indus- trial sector, the supply and availability of potable water have become a global concern. Increased industrial activities lead to the production of contaminated effluents, rich for instance in toxic metals that are placed directly into the environment. In that sense, the toxicity, persistence, and high bioaccumulation potential of metals are the most dangerous points to deal with. Cadmium, lead, arsenic, and mercury are the metals that stand out based on their toxicity levels. Mercury is considered the most dangerous among them by the US Environmental Protection Agency (EPA - United States Environmental Protection 1985). It is a natural element that can be found in the four subsystems of planet Earth (geosphere, hydrosphere, biosphere, and atmosphere) in several possible forms. The organic forms, such as methyl mercury and ethyl mercury, and the elemental form are neurotoxic, and the inorganic forms, such as mercury chloride, are mainly nephrotoxic (Oliveira et al. 2007; UNEP, 2013). Many methodologies have been developed for the determi- nation of mercury in aqueous matrices. The techniques employed are the most diverse such as UV-Vis molecular absorption (Babu and Reddy 2012), molecular fluorimetry (Liang et al. 2018), atomic fluorescence spectrometry (AFS) (Schlathauer et al. 2017), inductively coupled plasma optical emission spectrometry (ICP-OES) (Wuilloud et al. 2002), in- ductively coupled plasma mass spectrometry (ICP-MS) (Allibone et al. 1999), atomic absorption spectrometry (Sobhi et al. 2017), or voltammetry (Martín-Yerga et al. 2013). However, the instrumentation necessary to many of these methodologies is expensive, making them inaccessible to some research groups. Also, for most of these techniques, except for ICP-MS, the quantification of mercury species in effluents is strongly affected by concomitants present in the Responsible editor: Severine Le Faucheur * Fernanda N. Feiteira fnfeiteira@id.uff.br 1 UFF - Universidade Federal Fluminense, Niterói, RJ, Brazil 2 CEFET/RJ - Centro Federal de Educação Tecnológica Celso Suckow da Fonseca, Petrópolis, RJ, Brazil Environmental Science and Pollution Research https://doi.org/10.1007/s11356-019-05178-y