DataSheet1_Cucurbituril—assisted sensitive fluorescence detection and quantitation of naproxen drug in wastewater samples: Guest-host characterization and HPLC investigation.PDF

Sensitive spectrofluorometric and liquid chromatography with fluorescence detection methods have been developed for detection and determination of naproxen drug in the presence of cucurbit7uril (CB7). Fluorescence signals have been improved with the addition of CB7 to the drug aqueous solution. Fluorescence spectroscopy, mass spectrometry, 1H-NMR, and liquid chromatography with fluorescence detection were used to investigate the guest-host interaction of naproxen drug and cucurbiturils. Naproxen was found to form a supramolecular complex with CB7 that had a high formation constant. The optimal conditions for the interaction were discovered using spectroflurometry to be 0.2 mg/ml of CB7, 2.4 μg/ml of naproxen drug, and pH10. A 1:1 complex between naproxen and CB7 is revealed by proton NMR and tandem mass spectrometry. Using the standard addition calibration method, an HPLC with a fluorescence detector was used to detect naproxen in influent and effluent wastewater samples. Finally, it was discovered that the measured concentrations of naproxen in the influent and the effluent wastewater were 1.87 × 10−4 ppb and 2.1 × 10−5 ppb, respectively. This was done by sample enrichment, which reduced the 1000 mL into 1 ml.</p

DataSheet2_Cucurbituril—assisted sensitive fluorescence detection and quantitation of naproxen drug in wastewater samples: Guest-host characterization and HPLC investigation.docx

Sensitive spectrofluorometric and liquid chromatography with fluorescence detection methods have been developed for detection and determination of naproxen drug in the presence of cucurbit7uril (CB7). Fluorescence signals have been improved with the addition of CB7 to the drug aqueous solution. Fluorescence spectroscopy, mass spectrometry, 1H-NMR, and liquid chromatography with fluorescence detection were used to investigate the guest-host interaction of naproxen drug and cucurbiturils. Naproxen was found to form a supramolecular complex with CB7 that had a high formation constant. The optimal conditions for the interaction were discovered using spectroflurometry to be 0.2 mg/ml of CB7, 2.4 μg/ml of naproxen drug, and pH10. A 1:1 complex between naproxen and CB7 is revealed by proton NMR and tandem mass spectrometry. Using the standard addition calibration method, an HPLC with a fluorescence detector was used to detect naproxen in influent and effluent wastewater samples. Finally, it was discovered that the measured concentrations of naproxen in the influent and the effluent wastewater were 1.87 × 10−4 ppb and 2.1 × 10−5 ppb, respectively. This was done by sample enrichment, which reduced the 1000 mL into 1 ml.</p

Model for Photoinduced Bending of Slender Molecular Crystals

The growing realization that photoinduced bending of slender photoreactive single crystals is surprisingly common has inspired researchers to control crystal motility for actuation. However, new mechanically responsive crystals are reported at a greater rate than their quantitative photophysical characterization; a quantitative identification of measurable parameters and molecular-scale factors that determine the mechanical response has yet to be established. Herein, a simple mathematical description of the quasi-static and time-dependent photoinduced bending of macroscopic single crystals is provided. This kinetic model goes beyond the approximate treatment of a bending crystal as a simple composite bilayer. It includes alternative pathways for excited-state decay and provides a more accurate description of the bending by accounting for the spatial gradient in the product/reactant ratio. A new crystal form (space group <i>P</i>2₁/<i>n</i>) of the photoresponsive azo-dye Disperse Red 1 (<b>DR1</b>) is analyzed within the constraints of the aforementioned model. The crystal bending kinetics depends on intrinsic factors (crystal size) and external factors (excitation time, direction, and intensity)

Bioinspired Molecular Lantern: Tuning the Firefly Oxyluciferin Emission with Host–Guest Chemistry

Fireflies generate flashes of visible light via luciferase-catalyzed chemiexcitation of the substrate (luciferin) to the first excited state of the emitter (oxyluciferin). Microenvironment effects are often invoked to explain the effects of the luciferase active pocket on the emission; however, the exceedingly complex spectrochemistry and synthetic burdens have precluded elucidation of the nature of these interactions. To decipher the effects of microenvironment on the light emission, here the hydrophobic interior of cucurbit[7]­uril (CB7) is used to mimic the nonpolar active pocket of luciferase. The hydrophobic interior of CB7 induces shifts of the ground-state p<i>K</i>_as by 1.9–2.5 units to higher values. Upon sequestration, the emission maxima of neutral firefly oxyluciferin and its conjugate monodeprotonated base are blue-shifted by 40 and 39 nm, respectively, resulting in visual color changes of the emitted light

Redox-Responsive Viologen-Mediated Self-Assembly of CB[7]-Modified Patchy Particles

Sulfonated surface patches of poly­(styrene)-based colloidal particles (CPs) were functionalized with cucurbit[7]­uril (CB[7]). The macrocycles served as recognition units for diphenyl viologen (DPV²⁺), a rigid bridging ligand. The addition of DPV²⁺ to aqueous suspensions of the particles triggered the self-assembly of short linear and branched chainlike structures. The self-assembly mechanism is based on hydrophobic/ion-charge interactions that are established between DPV²⁺ and surface-adsorbed CB[7]. DPV²⁺ guides the self-assembly of the CPs by forming a ternary DPV²⁺⊂(CB­[7])₂ complex in which the two CB[7] macrocycles are attached to two different particles. Viologen-driven particle assembly was found to be both directional and reversible. Whereas sodium chloride triggers irreversible particle disassembly, the one-electron reduction of DPV²⁺ with sodium dithionite causes disassembly that can be reversed via air oxidation. Thus, this bottom-up synthetic supramolecular approach allowed for the reversible formation and directional alignment of a 2D colloidal material

Redox-Responsive Viologen-Mediated Self-Assembly of CB[7]-Modified Patchy Particles

Sulfonated surface patches of poly­(styrene)-based colloidal particles (CPs) were functionalized with cucurbit[7]­uril (CB[7]). The macrocycles served as recognition units for diphenyl viologen (DPV²⁺), a rigid bridging ligand. The addition of DPV²⁺ to aqueous suspensions of the particles triggered the self-assembly of short linear and branched chainlike structures. The self-assembly mechanism is based on hydrophobic/ion-charge interactions that are established between DPV²⁺ and surface-adsorbed CB[7]. DPV²⁺ guides the self-assembly of the CPs by forming a ternary DPV²⁺⊂(CB­[7])₂ complex in which the two CB[7] macrocycles are attached to two different particles. Viologen-driven particle assembly was found to be both directional and reversible. Whereas sodium chloride triggers irreversible particle disassembly, the one-electron reduction of DPV²⁺ with sodium dithionite causes disassembly that can be reversed via air oxidation. Thus, this bottom-up synthetic supramolecular approach allowed for the reversible formation and directional alignment of a 2D colloidal material