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Polyfluoroalkyl compounds (PFASs) are synthetic compounds recently classified as permanent and emerging chemicals ever since their bioaccumulation in humans and the environment, due to the presence of carbon–fluorine functional groups. The design of novel screening tools with addressed high response time for the routine quantification of PFASs in water is highly desirable. In this work, we propose the preparation of a new voltammetric sensor based on molecularly imprinted polymer nanoparticle (nanoMIP) receptors for the highly sensitive and selective quantification of PFASs in water. The nanoMIPs were synthesized by the solid phase approach and immobilized onto functionalized screen-printed platinum electrode (SPPtE), chosen as the transduction element for sensor development. Dimensional characterization of nanoMIPs by Dynamic light scattering (DLS) shows small nanosized imprinted particles (<200 nm) with a polydispersity index (PDI) below 0.3. Electrochemical techniques were used for sensor preparation, characterization, and to assess the analytical performance, respectively. Preliminary calibration curves of nanoMIP-based sensors in a wide range of PFAS concentrations (1.5–100 ng/mL) exhibited high sensitivity toward its target. [ABSTRACT FROM AUTHOR]

Here is presented a setup made of a combination of an injection valve, a hand‐made chromatographic microcolumn and an electrochemical detector for the simultaneous separation of Hg2+ and Ag+ ions in water. The microcolumns were packed with exchanger resin and used for the separation of Hg2+ and Ag+ ions, whereas a screen‐printed carbon electrode (SPCE) was the amperometric detector. The performances of the SPCE towards ions were firstly studied in a FIA setup. The efficiency of ion separation was then evaluated. The reproducibility, stability, and the regeneration of the obtained microcolumns were also studied and discussed. [ABSTRACT FROM AUTHOR]

Metal-free and Cu(II)-lipophilic porphyrins [H2Pp and Cu(II)Pp] loaded on titanium dioxide in the anatase phase (TiO2) were prepared and used as a heterogeneous catalyst for the photoreduction of Cr(VI) to Cr(III) in aqueous suspensions under UV–Vis light irradiation. TiO2 impregnated with copper(II) porphyrin [TiO2@Cu(II)Pp] was the most effective in photocatalyst reduction of toxic chromate Cr(VI) to non-toxic chromium Cr(III). We further evaluated an experimental design with the scope of fast optimization of the process conditions related to the use of TiO2 or TiO2-porphyrin based photocatalysts. A full factorial design as a chemometric tool was successfully employed for screening the affecting factors involved in photoconversion catalysis, with the modification of TiO2 both with porphyrin H2Pp and Cu(II)Pp. The studied experimental factors were the catalyst amount, the concentration of Cr(VI) ions, and the pH of the medium. The performed multivariate approach was successfully used for fast fitting and better evaluation of significant factors affecting the experimental responses, with the advantage of reducing the number of available experiments. Thus, the stability of the optimized TiO2 embedded Cu(II)Pp was investigated, confirming the high reproducibility and suitability for environmental purposes. [ABSTRACT FROM AUTHOR]