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This pilot study suggests that FPP AOT is a feasible intervention and the research protocol designed would be suitable, with minor modifications, for the conduction of a subsequent stage 2 trial designed to verify the hypothesis that the adjunct of FPP AOT might improve motor performance in individuals with IPD.

This work focuses on the extraction and determination of contaminants of environmental concern belonging to the classes of benzotriazoles and benzothiazoles from tap and raw river water samples. The sorbent, recently proposed by this research group, prepared by pyrolysis of humic acids (HAs) onto silica microparticles (HA-C@silica), was tested for fixed-bed SPE of benzotriazole and benzothiazole compounds by modulating its sorption affinity through the carbon loading. This was successfully increased from 10 to 20 wt% HAs and the obtained material, characterized by different techniques, provided quantitative adsorption at the sample native pH (7.5-8), for 50-250 mL samples spiked with each compound at the micrograms per litre levels. After extraction, the analytes were simultaneously desorbed by 4 mL methanol, even more reducible to small volume before HPLC-HESI-MS/MS analysis. Recovery was satisfactory for all compounds, ranging from 70 to 114%, with RSD values ≤ 16% (n = 3). The developed procedure allows quantitation of benzotriazoles at concentrations far below the environmental trigger limits. HA-C@silica turned out to be appealing in comparison with the commercial sorbents in terms of cost, recovery and pre-concentration for determination of such pollutants in actual surface waters. Good reproducibility was observed on independent HA-C@silica preparations.

We report the investigation of dicopper(II) bistren cryptate, containing naphthyl spacers between the tren subunits, as a receptor for polycarboxylates in neutral aqueous solution. An indicator displacement assay for dicarboxylates was also developed by mixing the azacryptate with the fluorescent indicator 5-carboxyfluorescein in a 50:1 molar ratio. Fluorimetric studies showed a significant restoration of fluorophore emission upon addition of fumarate anions followed by succinate and isophthalate. The introduction of hexyl chains on the naphthalene groups created a novel hydrophobic cage; the corresponding dicopper complex was investigated as an extractant for dicarboxylates from neutral water into dichloromethane. The liquid–liquid extraction of succinate—as a model anion—was successfully achieved by exploiting the high affinity of this anionic guest for the azacryptate cavity. Extraction was monitored through the changes in the UV–visible spectrum of the dicopper complex in dichloromethane and by measuring the residual concentration of succinate in the aqueous phase by HPLC-UV. The successful extraction was also confirmed by 1 H-NMR spectroscopy. Considering the relevance of polycarboxylates in biochemistry and in the environmental field, e.g., as waste products of industrial processes, our results open new perspectives for research in all contexts where recognition, sensing, or extraction of polycarboxylates is required.