Controllable self-assembling of gold nanorods via on and off supramolecular noncovalent interactions

Cucurbit[7]uril Induced Formation of FRET-Enabled Unilamellar Lipid Vesicles

A unique fluorescence resonance energy transfer (FRET) process is found to be operational in a unilamellar lipid self-assembly in the aqueous phase. A newly synthesized naphthyl based long chain lipid derivative [N-(naphthalene-1-ylmethyl)tetradecane-1-ammonium chloride, 14NA⁺] forms various self-assembled architectures in the aqueous phase. Controlled changes in lipid concentration lead to a transition of the self-assemblies from micelles to vesicles to rods. In the presence of cucurbit[7]uril (CB7), 14NA⁺ forms a host-guest [2]pseudorotaxane complex (CB7∋14NA⁺) and secondary interactions lead to the formation of a lipid bilayer with hydrophobic pockets situated in between the layers. The change in the structure of 14NA⁺ assemblies, interaction with CB7 and formation of supramolecular assemblies of CB7∋14NA⁺ were examined using light scattering, spectroscopic, and microscopic techniques. Entrapment of a luminescent dye, anthracene within the hydrophobic bilayer of the supramolecular assembly CB7∋14NA⁺ favors a modified luminescent response due to an efficient FRET process. Further, the FRET process could be controlled by thermal and chemical stimuli that induce transformation of unilamellar vesicles.

End-to-end assembly and disassembly of gold nanorods based on photo-responsive host–guest interaction

The end-to-end assembly and disassembly of gold nanorods were realized via HS-β-CD recognition and controllable by both UV light irradiation and guest competition.

Synthesis of a disulfide-bridged bispillar[5]arene and its application in supramolecular polymers

A disulfide-bridged bispillar[5]arene was synthesized efficiently and applied to fabricate supramolecular polymers, which were redox-responsive and could be used to prepare fluorescent water-dispersible nanospheres.

A pillar[6]arene-based [2]pseudorotaxane in solution and in the solid state and its photo-responsive self-assembly behavior in solution

A pillar[6]arene-based [2]pseudorotaxane was constructed in solution and studied in the solid state, and its photo-responsive self-assembly behavior in solution was investigated.

A simple pincer-type chemosensor for reversible fluorescence turn-on detection of zinc ion at physiological pH range

A dihydrazone based pincer-type chemosensor (Y) which could detect zinc at physiological pH range with reversible fluorescence “Off–On–Off”.

Strong plasmon-exciton coupling in a hybrid system of gold nanostars and J-aggregates

Hybrid materials formed by plasmonic nanostructures and J-aggregates provide a unique combination of highly localized and enhanced electromagnetic field in metal constituent with large oscillator strength and extremely narrow exciton band of the organic component. The coherent coupling of localized plasmons of the multispiked gold nanoparticles (nanostars) and excitons of JC1 dye J-aggregates results in a Rabi splitting reaching 260 meV. Importantly, broad absorption features of nanostars extending over a visible and near-infrared spectral range allowed us to demonstrate double Rabi splitting resulting from the simultaneous coherent coupling between plasmons of the nanostars and excitons of J-aggregates of two different cyanine dyes.

Porphyrin metal complex monolayer-protected gold nanorods: a parallel facile synthesis and self-assembly

Porphyrin metal (Zn, Cu, and Mg) complex monolayer-protected gold nanorods (GNRs) were, for the first time, synthesized. Their synthesis was easy to access by mixing porphyrin encapsulated GNRs with corresponding excess soluble metal salts in solution, followed by the facile purification through centrifugation and sonication due to the gravity of the GNRs and their solubility in organic solvents. Furthermore, the resulting three GNRs exhibited distinct spectroscopic properties and were able to self-assemble into side-by-side arrays driven by π-π intermolecular interactions of the surface metal porphyrin chromophores.