l-Proline induced self-assembly of indolicidin derived palindromic tripeptide

Controllable supramolecular self-assemblies (rods–wires–spheres) and ICT/PET based perylene probes for palladium detection in solution and the solid state

AC-PDIshows solvent dependent self-assembly into nanowires, rods and spheres. It could be used for detection of Pd⁰in 50% HEPES buffer–DMSO (39 nM, UV-Vis; 45 nM, fluorescence) and the solid state (0.58 pg cm⁻²).

AIE + ESIPT based red fluorescent aggregates for visualization of latent fingerprints

DPSA shows applications in establishing the individuality of three subjects using the 1st (pattern of arch, loop or whorl) and 2nd (minutiae details of dots, ridge ending, core and delta) level of information.

Perylene diimide-based organic π-motif for differentiating CN− and F− ions by electron-transfer and desilylation mechanisms: applications to complex logic circuits

PDI-SiHQ undergoes electron-transfer and desilylation reactions with CN⁻ and F⁻ ions to differentiate basic anions.

Self-assembled vesicle and rod-like aggregates of functionalized perylene diimide: reaction-based near-IR intracellular fluorescent probe for selective detection of palladium

Aggregates ofPS-PDIafter Pd⁰based depropargylation show de-aggregation and near-IR, ratiometric absorbance changes in water and live HeLa cells.

Tunable control of polyproline helix (PPII) structure via aromatic electronic effects: an electronic switch of polyproline helix

Aromatic rings exhibit defined interactions via the unique aromatic π face. Aromatic amino acids interact favorably with proline residues via both the hydrophobic effect and aromatic-proline interactions, C-H/π interactions between the aromatic π face and proline ring C-H bonds. The canonical aromatic amino acids Trp, Tyr, and Phe strongly disfavor a polyproline helix (PPII) when they are present in proline-rich sequences because of the large populations of cis amide bonds induced by favorable aromatic-proline interactions (aromatic-cis-proline and proline-cis-proline-aromatic interactions). We demonstrate the ability to tune polyproline helix conformation and cis-trans isomerism in proline-rich sequences using aromatic electronic effects. Electron-rich aromatic residues strongly disfavor polyproline helix and exhibit large populations of cis amide bonds, while electron-poor aromatic residues exhibit small populations of cis amide bonds and favor polyproline helix. 4-Aminophenylalanine is a pH-dependent electronic switch of polyproline helix, with cis amide bonds favored as the electron-donating amine, but trans amide bonds and polyproline helix preferred as the electron-withdrawing ammonium. Peptides with block proline-aromatic PPXPPXPPXPP sequences exhibited electronically switchable pH-dependent structures. Electron-poor aromatic amino acids provide special capabilities to integrate aromatic residues into polyproline helices and to serve as the basis of aromatic electronic switches to change structure.