Publications by authors named "Sergio de Rooy"

In this study, three magnetic ionic liquids (MILs) were investigated for extraction of four estrogens, i.e., estrone (E1), estradiol (E2), estriol (E3), and ethinylestradiol (EE2), from environmental water.

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There is a continuing need to develop high-performance sensors for monitoring organic solvents, primarily due to the environmental impact of such compounds. In this regard, colorimetric sensors have been a subject of intense research for such applications. Herein, we report a unique virtual colorimetric sensor array based on a single ionic liquid (IL) for accurate detection and identification of similar organic solvents and mixtures of such solvents.

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A novel pH sensitive, colorimetric ionic liquid nanosensor based on phosphonium salts of fluorescein is reported. Herein, fluorescein salts of various stoichiometries were synthesized by use of a trihexyltetradecylphosphonium cation [TTP] in combination with dianionic [FL] and monoanionic [FL] fluorescein. Nanomaterials derived from these two compounds yielded contrasting colorimetric responses in neutral and acidic environments.

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The research literature currently abounds with studies of graphene-related materials as a result of the extraordinary properties of such materials. On the basis of these citations, it is clear that the range of applications for such materials is substantial. In this manuscript, we report the immobilization of graphene oxide (GO) onto a fused-silica capillary to form a potential stationary phase for use in open-tubular CEC.

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The ability to control the morphologies and spectral properties of organic low-dimensional nanomaterials is of paramount importance. The research reported herein demonstrates a template-free approach to tailored morphological and optical properties for a novel class of pseudoisocyanine (PIC)-based fluorescent organic nanoparticles derived from a group of uniform materials based on organic salts (GUMBOS). The synthesized nanoscale PIC-based particles (termed nanoGUMBOS), [PIC][NTf(2)] and [PIC][BETI], exhibit interesting adaptability as a function of the associated anion.

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Groups of uniform materials based on organic salts (GUMBOS), derived from thiacarbocyanine (TC)-based dyes with increasing methyne chain lengths, were prepared through a single-step metathesis reaction between the iodide form of the TC dye and lithium bis(perfluoroethylsulfonyl)imide as the lipophilic anion source. Ionic self-assembly of these fluorescent hydrophobic GUMBOS resulted in aqueous dispersions of one-dimensional micro-and nano-scale molecular aggregates. Blended binary and ternary aggregates containing multiple TC GUMBOS were also prepared.

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Multifunctional phosphonium-lanthanide compounds that simultaneously possess paramagnetism, luminescence, and tumor mitochondrial targeting properties were prepared by use of a facile method. These compounds were fully characterized by use of (1)H, (13)C, (31)P NMR, FT-IR, and elemental analyses. The thermal properties of these compounds including melting points and decomposition temperatures were investigated using DSC and TGA analyses.

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Microstructures of sodium deoxycholate hydrogels were altered considerably in the presence of variable tris(hydroxymethyl)aminomethane (TRIS) concentrations. These observations were confirmed by use of X-ray diffraction, polarized optical microscopy, rheology, and differential scanning calorimetry measurements. Our studies reveal enhanced gel crystallinity and rigidity with increasing TRIS concentrations.

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A hydrophobic magnetic room temperature ionic liquid (MRTIL), trihexyltetradecylphosphonium tetrachloroferrate(III) ([3C(6)PC(14)][FeCl(4)]), was synthesized from trihexyltetradecylphosphonium chloride and FeCl(3) · 6H(2)O. This MRTIL was investigated as a possible separation agent for solvent extraction of phenolic compounds from aqueous solution. Due to its strong paramagnetism, [3C(6)PC(14)][FeCl(4)] responds to an external neodymium magnet, which was employed in the design of a novel magnetic extraction technique.

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Herein we report the synthesis of a fluorescent organic salt through anion exchange and the subsequent fabrication of 1D-nanostructures via a facile templating method.

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We report the synthesis of a series of novel structurally related protic chiral ionic liquids (PCILs) derived from ephedrines. Enantiopure norephedrine, ephedrine, and methylephedrine were neutralized by use of fluorinated acids, bis(trifluoromethanesulfonyl)imide, and bis(pentafluoroethanesulfonyl)imide to afford six PCILs with protonated primary, secondary, and tertiary amines. The goal of this study is to investigate the influence of structure on both chiral recognition abilities and physicochemical properties of these closely related PCILs.

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Template-free controlled aggregation and spectral properties in fluorescent organic nanoparticles (FONs) is highly desirable for various applications. Herein, we report a nontemplated method for controlling the aggregation in near-infrared (NIR) cyanine-based nanoparticles derived from a group of uniform materials based on organic salts (GUMBOS). Cationic heptamethine cyanine dye 1,1',3,3,3',3'-hexamethylindotricarbocyanine (HMT) was coupled with five different anions, viz.

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Novel room temperature magnetic chiral ionic liquids derived from amino acids were synthesized and their magnetic properties as well as chiral discrimination abilities were investigated.

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A parallel library of chiral ionic liquid (CIL)-modified silanes as potential chiral selectors was synthesized, and their enantiomeric discrimination abilities were screened by use of (19)F NMR spectroscopy. The screening method allows for rapid identification of the most enantioselective members of the library and simultaneous investigation of their chiral recognition mechanisms. The library compounds were synthesized using quaternization and anion-exchange reactions.

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