A colour-tunable chiral AIEgen: reversible coordination, enantiomer discrimination and morphology visualization.

We present a conceptually new approach to synthesise a boron-containing Aggregation-Induced Emissive Luminogen (AIEgen) with a chiral chromophore. An intramolecular N-B coordinating bond results in a low-energy transition that renders the material red-emissive in a solid state. By competitive binding of nucleophiles to the boron atom, this bond is replaced in favour of an intermolecular coordinating bond, which results in a tremendous blue-shift in both the absorption and emission.

Circularly-Polarized Luminescence (CPL) from Chiral AIE Molecules and Macrostructures.

Circularly-polarized luminescence (CPL) has received new attention on the rise of applications to generate devices and biologically active probes. These applications require fluorophores that are not only chiral but also provide strong fluorescence intensity in aggregated state. Thus, a new research branch has opened up a few years ago, which allows CPL-active fluorophores to be emissive in aggregated-state.

Aggregation-induced emissive nanoparticles for fluorescence signaling in a low cost paper-based immunoassay.

Low cost paper based immunoassays are receiving interest due to their fast performance and small amounts of biomolecules needed for developing an immunoassay complex. In this work aggregation-induced emissive (AIE) nanoparticles, obtained from a diastereoisomeric mixture of 1,2-di-(4-hydroxyphenyl)-1,2-diphenylethene (TPEDH) in a one-step top-down method, are characterized through Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Zeta potential. By measuring the Zeta potential before and after labeling the nanoparticles with antibodies we demonstrate that the colloidal system is stable in a wide pH-range.

A Luminescent Nitrogen-Containing Polycyclic Aromatic Hydrocarbon Synthesized by Photocyclodehydrogenation with Unprecedented Regioselectivity.

We present a nitrogen-containing polycyclic aromatic hydrocarbon (N-PAH), namely 12-methoxy-9-(4-methoxyphenyl)-5,8-diphenyl-4-(pyridin-4-yl)pyreno[1,10,9-h,i,j]isoquinoline (c-TPE-ON), which exhibits high quantum-yield emission both in solution (blue) and in the solid state (yellow). This molecule was unexpectedly obtained by a three-fold, highly regioselective photocyclodehydrogenation of a tetraphenylethylene-derived AIEgen. Based on manifold approaches involving UV/Vis, photoluminescence, and NMR spectroscopy as well as HRMS, we propose a reasonable mechanism for the formation of the disk-like N-PAH that is supported by density functional theory calculations.

Chirality transfer in 1D self-assemblies: influence of H-bonding vs metal coordination between dicyano[7]helicene enantiomers.

Chiral recognition as well as chirality transfer in supramolecular self-assembly and on-surface coordination is studied for the enantiopure 6,13-dicyano[7]helicene building block. It is remarkable that, with this helical molecule, both H-bonded chains and metal-coordinated chains can be formed on the same substrate, thereby allowing for a direct comparison of the chain bonding motifs and their effects on the self-assembly in experiment and theory. Conformational flexure and both adsorbate/adsorbent and intermolecular interactions can be identified as factors influencing the chiral recognition at the binding site.

Structural manipulation of colloidal silica.

Structural properties of the nanosized silica Ludox TMA with novel functionalizations have been investigated. Silica is stabilized in aqueous solution at a pH value higher than the pK(a) of silicic acid. A surface modification consisting of poly(p-benzamide)s functionalized with derivatized nucleobases on the C-terminus and cationic pyridinium functions on the N-terminus of the polymer chain was carried out.