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A bis‐tryptophan tweezer was installed on a polyoxometalate (POM) surface via a bis‐amide covalent bond, yielding the enantiopure hybrid POM with C2 symmetry, as a result of the regioselective functionalization of decatungosilicate [γ‐SiW10O36]8– at the lacunary site. The combined polyanionic and receptor properties are instrumental for a POM‐driven solubilization and enrichment of single walled carbon nanotubes (SWCNTs) with diameter <1.1 nm, as demonstrated by Raman and UV/Vis‐NIR evidence, in agreement with the calculated energetics of the tryptophan tweezer–SWCNT interaction. The preference of SWCNT(9,3) to interact within a tryptophan‐based hydrophobic pocket is demonstrated by experimental and computational evidence, addressing the selective binding of a polyoxometalate‐based tweezer [ABSTRACT FROM AUTHOR]

Novel organic‐inorganic polyoxometalates (POMs) decorated with covalent fluorescent tags have been designed for cell internalization. Their localization within model HEK cells is readily accomplished by confocal fluorescence microscopy. While cell internalization is dictated by the formation of the amphiphilic POM‐based nanostructures, their cytoplasmic‐nuclear trafficking appears to be regulated by a subtle interplay of the organic‐inorganic domains of the nanoassemblies which, in turn, impacts their dynamic behavior and capability to interact with cell membranes. Polyoxometalates with appended fluorescent tags form nanoparticles that can internalize into cells, with a localization depending on their composition. [ABSTRACT FROM AUTHOR]

In this study, a new organic–inorganic material, based on an alpha-metatungstate [H 2 W 12 O 40 ] 6 − cluster, was synthesized via the hydrothermal method by using aminopyridinium (APy) + cations as the hybrid material, and characterized by FT-IR and UV spectra analysis. The hybrid composite was immobilized on a gold electrode decorated with gold nanoparticles (AuNPs) and the modified electrode exhibited excellent electrocatalytic activities towards the reduction of H 2 O 2 at neutral pH with a response time of < 10 s. The H 2 O 2 response at the modified electrode displays a linear response ranging from 40 μM to 10 mM. Based on the H 2 O 2 reduction activity, the (APy) 6 [H 2 W 12 O 40 ] composite was successfully used for the fabrication of a novel enzymatic glucose biosensor. The glucose oxidase enzyme (GOx) was immobilized onto the hybrid composite on AuNPs/gold electrodes; the (APy) 6 [H 2 W 12 O 40 ] composites were used as both mediation and bridging molecules. A multilayer architecture was constructed from hybrid POM alternating with (GOx), using glutaraldehyde as a covalent attachment cross-linker. Cyclic voltammetry (CV), SWV and chronoamperometry were used to determine the electrochemical properties of the mediator and characterize its reaction with (GOx). The resulting glucose biosensor exhibits a wide linear response for glucose from 40 μM to 10 mM with a sensitivity of 15.0 μA mM − 1 . [ABSTRACT FROM AUTHOR]

The desulfurization efficiency of various hybrid zinc-substituted polyoxometalates ([PW 11 Zn(H 2 O)O 39 ] 5 − , abbreviated as PW 11 Zn) was here investigated for the first time and optimized using sustainable systems conciliating successfully the liquid–liquid extraction and the oxidative catalytic process. Initially, the desulfurization studies were performed using a model diesel containing a mixture of the most refractory sulfur compounds and later extended to an untreated real diesel. In both cases, acetonitrile was used as extraction solvent and aqueous H 2 O 2 as oxidant. High level of desulfurization was achieved using model and untreated diesels after few hours. The quaternary ammonium catalysts (TBAPW 11 Zn and ODAPW 11 Zn) showed higher catalytic desulfurization efficiency than the ionic liquid catalyst (BMIPW 11 Zn). The TBAPW 11 Zn behaved as a homogeneous catalyst immobilized in the extraction solvent, while the ODAPW 11 Zn with the long carbon chain behaved as a heterogeneous catalyst capable to be recovered from the system. Both quaternary ammonium catalysts showed to be successfully reused/recycled for various consecutive desulfurization cycles. [ABSTRACT FROM AUTHOR]