Anion Recognition Triggered Nanoribbon-Like Self-Assembly: A Fluorescent Chemosensor for Nitrate in Acidic Aqueous Solution and Living Cells

A water-soluble π-conjugated bispyridinium phenylenevinylene-based fluorogenic probe has been developed as a novel fluorescent chemosensor for highly selective, sensitive, and rapid detection of NO₃^– anion in acidic aqueous media. This system self-assembles to a nanoribbon as a result of ionic interaction. The positively charged chemosensor generates a nearly instantaneous significant fluorescence signal (475 vs 605 nm) in response to NO₃^– in the green/yellow spectral region, with a large Stokes shift (130 nm). The fluorescence changes can be attributed to the self-aggregation of the sensor triggered by ionic interaction, which occurs as a consequence of the subtle cooperation of electrostatic ionic bonding, van der Waals forces, and π-stacking of the π-conjugated aromatic moieties. Importantly, this chemosensor has been employed for the first time for the fluorescence detection of intracellular NO₃^– anion in cultured cells

White Light Emission from Cucurbituril-Based Host–Guest Interaction in the Solid State: New Function of the Macrocyclic Host

Energy transfer and interchange are central for fabricating white light-emitting organic materials. However, increasing the efficiency of light energy transfer remains a considerable challenge because of the occurrence of “cross talk”. In this work, by exploiting the unique photophysical properties of cucurbituril-triggered host–guest interactions, the two complementary luminescent colors blue and yellow for white light emission were independently obtained from a single fluorophore dye rather than energy transfer. Further study suggested that the rigid cavity of cucurbiturils efficiently prevented the aggregation of the dye and improved its thermal stability in the solid state by providing a regular nanosized fence for each encapsulated dye molecule. As a result, a novel macrocycle-assisted supramolecular approach for obtaining solid, white light-emitting organic materials with low cost, high efficiency, and easy scale-up was successfully demonstrated

White Light Emission from Cucurbituril-Based Host–Guest Interaction in the Solid State: New Function of the Macrocyclic Host

Energy transfer and interchange are central for fabricating white light-emitting organic materials. However, increasing the efficiency of light energy transfer remains a considerable challenge because of the occurrence of “cross talk”. In this work, by exploiting the unique photophysical properties of cucurbituril-triggered host–guest interactions, the two complementary luminescent colors blue and yellow for white light emission were independently obtained from a single fluorophore dye rather than energy transfer. Further study suggested that the rigid cavity of cucurbiturils efficiently prevented the aggregation of the dye and improved its thermal stability in the solid state by providing a regular nanosized fence for each encapsulated dye molecule. As a result, a novel macrocycle-assisted supramolecular approach for obtaining solid, white light-emitting organic materials with low cost, high efficiency, and easy scale-up was successfully demonstrated

Through-Space Conjugated Supramolecular Polymer Radicals from Spatial Organization of Cucurbit[8]uril: An Efficient Approach for Electron Transfer and Smart Photochromism Materials

Electron transfer-based long-lived radicals are highly challenging because of the limited control over relative orientation, distance, electronic coupling, and nonradiative recombination channels of the donor and acceptor on a molecular level. Herein, the cavity of macrocyclic cucurbit[8]uril (Q[8]) was found to exhibit excellent advantages in controlling the relative orientation and distance of the donor and acceptor moieties via the spatial organization, i.e., the 4-carboxylphenyl appended viologen-derived guest (BcpV2+) was elegantly rearranged as a rigid linear J-type supramolecular polymer by the Q[8] host via noncovalent interactions. Thus, an unprecedented photoinduced electron transfer (PET) triggered through-space conjugated organic radical with distinct photochromism and a NIR-II photothermal effect was observed. Further studies have indicated that the Q[8] encapsulation-triggered PET cycle exhibited good repeatability without significant loss of its efficiency and had potential application in the fabrication of smart windows and erasable printing under photoirradiation or sunlight. These results suggest that the Q[8] host can be used as a new tool in light-energy conversion and photochromism materials science

Through-Space Conjugated Supramolecular Polymer Radicals from Spatial Organization of Cucurbit[8]uril: An Efficient Approach for Electron Transfer and Smart Photochromism Materials

Electron transfer-based long-lived radicals are highly challenging because of the limited control over relative orientation, distance, electronic coupling, and nonradiative recombination channels of the donor and acceptor on a molecular level. Herein, the cavity of macrocyclic cucurbit[8]uril (Q[8]) was found to exhibit excellent advantages in controlling the relative orientation and distance of the donor and acceptor moieties via the spatial organization, i.e., the 4-carboxylphenyl appended viologen-derived guest (BcpV2+) was elegantly rearranged as a rigid linear J-type supramolecular polymer by the Q[8] host via noncovalent interactions. Thus, an unprecedented photoinduced electron transfer (PET) triggered through-space conjugated organic radical with distinct photochromism and a NIR-II photothermal effect was observed. Further studies have indicated that the Q[8] encapsulation-triggered PET cycle exhibited good repeatability without significant loss of its efficiency and had potential application in the fabrication of smart windows and erasable printing under photoirradiation or sunlight. These results suggest that the Q[8] host can be used as a new tool in light-energy conversion and photochromism materials science

Through-Space Conjugated Supramolecular Polymer Radicals from Spatial Organization of Cucurbit[8]uril: An Efficient Approach for Electron Transfer and Smart Photochromism Materials

Electron transfer-based long-lived radicals are highly challenging because of the limited control over relative orientation, distance, electronic coupling, and nonradiative recombination channels of the donor and acceptor on a molecular level. Herein, the cavity of macrocyclic cucurbit[8]uril (Q[8]) was found to exhibit excellent advantages in controlling the relative orientation and distance of the donor and acceptor moieties via the spatial organization, i.e., the 4-carboxylphenyl appended viologen-derived guest (BcpV2+) was elegantly rearranged as a rigid linear J-type supramolecular polymer by the Q[8] host via noncovalent interactions. Thus, an unprecedented photoinduced electron transfer (PET) triggered through-space conjugated organic radical with distinct photochromism and a NIR-II photothermal effect was observed. Further studies have indicated that the Q[8] encapsulation-triggered PET cycle exhibited good repeatability without significant loss of its efficiency and had potential application in the fabrication of smart windows and erasable printing under photoirradiation or sunlight. These results suggest that the Q[8] host can be used as a new tool in light-energy conversion and photochromism materials science

Through-Space Conjugated Supramolecular Polymer Radicals from Spatial Organization of Cucurbit[8]uril: An Efficient Approach for Electron Transfer and Smart Photochromism Materials

Electron transfer-based long-lived radicals are highly challenging because of the limited control over relative orientation, distance, electronic coupling, and nonradiative recombination channels of the donor and acceptor on a molecular level. Herein, the cavity of macrocyclic cucurbit[8]uril (Q[8]) was found to exhibit excellent advantages in controlling the relative orientation and distance of the donor and acceptor moieties via the spatial organization, i.e., the 4-carboxylphenyl appended viologen-derived guest (BcpV2+) was elegantly rearranged as a rigid linear J-type supramolecular polymer by the Q[8] host via noncovalent interactions. Thus, an unprecedented photoinduced electron transfer (PET) triggered through-space conjugated organic radical with distinct photochromism and a NIR-II photothermal effect was observed. Further studies have indicated that the Q[8] encapsulation-triggered PET cycle exhibited good repeatability without significant loss of its efficiency and had potential application in the fabrication of smart windows and erasable printing under photoirradiation or sunlight. These results suggest that the Q[8] host can be used as a new tool in light-energy conversion and photochromism materials science

Through-Space Conjugated Supramolecular Polymer Radicals from Spatial Organization of Cucurbit[8]uril: An Efficient Approach for Electron Transfer and Smart Photochromism Materials

Electron transfer-based long-lived radicals are highly challenging because of the limited control over relative orientation, distance, electronic coupling, and nonradiative recombination channels of the donor and acceptor on a molecular level. Herein, the cavity of macrocyclic cucurbit[8]uril (Q[8]) was found to exhibit excellent advantages in controlling the relative orientation and distance of the donor and acceptor moieties via the spatial organization, i.e., the 4-carboxylphenyl appended viologen-derived guest (BcpV2+) was elegantly rearranged as a rigid linear J-type supramolecular polymer by the Q[8] host via noncovalent interactions. Thus, an unprecedented photoinduced electron transfer (PET) triggered through-space conjugated organic radical with distinct photochromism and a NIR-II photothermal effect was observed. Further studies have indicated that the Q[8] encapsulation-triggered PET cycle exhibited good repeatability without significant loss of its efficiency and had potential application in the fabrication of smart windows and erasable printing under photoirradiation or sunlight. These results suggest that the Q[8] host can be used as a new tool in light-energy conversion and photochromism materials science

Through-Space Conjugated Supramolecular Polymer Radicals from Spatial Organization of Cucurbit[8]uril: An Efficient Approach for Electron Transfer and Smart Photochromism Materials

Electron transfer-based long-lived radicals are highly challenging because of the limited control over relative orientation, distance, electronic coupling, and nonradiative recombination channels of the donor and acceptor on a molecular level. Herein, the cavity of macrocyclic cucurbit[8]uril (Q[8]) was found to exhibit excellent advantages in controlling the relative orientation and distance of the donor and acceptor moieties via the spatial organization, i.e., the 4-carboxylphenyl appended viologen-derived guest (BcpV2+) was elegantly rearranged as a rigid linear J-type supramolecular polymer by the Q[8] host via noncovalent interactions. Thus, an unprecedented photoinduced electron transfer (PET) triggered through-space conjugated organic radical with distinct photochromism and a NIR-II photothermal effect was observed. Further studies have indicated that the Q[8] encapsulation-triggered PET cycle exhibited good repeatability without significant loss of its efficiency and had potential application in the fabrication of smart windows and erasable printing under photoirradiation or sunlight. These results suggest that the Q[8] host can be used as a new tool in light-energy conversion and photochromism materials science

Facile Cucurbit[8]uril-Based Supramolecular Approach To Fabricate Tunable Luminescent Materials in Aqueous Solution

Light-emitting materials with tunable properties may offer fascinating applications in optoelectronic devices, fluorescent sensors, and imaging agents. Herein, a new supramolecular approach based on host–guest interactions that greatly decreases the number of required synthetic steps and produces a system with tunable and dynamical photophysical properties was developed. Because of the novel electronic distributions of the chromophore guest within the rigid hydrophobic cavity of the cucurbit[8]­uril host in this system, color tuning of emissions such as cyan, yellow, green, and white light with efficiency increased fluorescence lifetime, and quantum yield was easily achieved by simple addition of the host in aqueous solution. Stimulus-responsive tuning of color has long been an important area of research into light emissions. The current study distinguishes itself by its combination of simple steps using a single synthetic receptor and a single organic fluorophore guest in a single solution. Our results may provide a promising advancement of the fabrication of smart and tunable luminescent materials