Multiple Applications\nof Chiral Self-Assembled H<sub>8</sub>–BINOL Nanoprobes with\nAIE-ESIPT Characteristics: Chiral\nSwitching and pH Visualization Detection

<i>R</i>-<b>BTOBD</b> exhibited significant\naggregation-induced\nEmission (AIE) characteristics, including high brightness (αAIE\n≈ 40), robust light stability, a substantial Stokes shift (128\nnm), and a high signal-to-noise ratio, effectively overcoming aggregation-caused\nquenching (ACQ). Derived from the axially chiral <i>R</i>-H<sub>8</sub>–BINOL, <i>R</i>-<b>BTOBD</b> was synthesized via nucleophilic cyclization and exhibited pronounced\nself-assembly properties. Through robust intra- and intermolecular\nhydrogen bonding interactions, <i>R</i>-<b>BTOBD</b> formed diverse supramolecular structures, including spherical flower-like\naggregates, hollow-core triangular tubules, hexagonal tubules, and\nirregular white block-like stacks. The specific morphology was influenced\nby factors such as solvent and pH. For fluorescence applications, <i>R</i>-<b>BTOBD</b> can be employed as an effective visual\npH detector through an AIE-enhanced excited-state intramolecular proton\ntransfer (AIE-ESIPT) mechanism. When incorporated into pH paper, it\nexhibited a bright yellow fluorescence across a wide pH range (pH\n1–11), transitioning to an intense bright blue fluorescence\nunder strongly basic conditions (pH 12–14). In chiral applications, <i>R</i>-<b>BTOBD</b> demonstrated potential as a chiral\nswitching agent, leveraging the pronounced changes and inversions\nin its circular dichroism (CD) signals under varying aggregation states\nand pH conditions. Additionally, it serves as a specific chiral enantioselective\nfluorescence probe for l-lysine, demonstrating high efficiency\nand a low detection limit. Given its exceptional fluorescence and\nchiral properties, this fluorescent material has significant potential\nfor diverse applications in fluorescence, chirality, and visual inspection.