Metal-ion-mediated synergistic coordination: construction of AIE-metallogel sensor arrays for anions and amino acids

Abstract

Supramolecular gels with aggregation-induced emission (AIE) are recognized as excellent chemosensors. The combination of gelators and metal ions gives rise to a synergistic effect, which induces functional behaviors of anions and amino acids. The 3,4,5-tris(hexadecyl) benzoyl hydrazine functionalized naphthalimide gelator (G) with multi self-assembly driving forces was devised and synthesized. G could self-assemble into a stable supramolecular organogel (OG) in cyclohexanol solution with blue-green AIE. Notably, the OG could coordinate with different metal ions through coordination bonds to form a series of metallogels (OGMs). In addition, these metallogels (OGMs) could selectively sense various anions (I⁻, N₃⁻, CN⁻) and amino acids (L-Trp and L-His) via synergistic coordination interaction between target ions/amino acids and pre-assembling metal ions in OGMs. Therefore, a six-membered anion and amino acid sensor array based on supramolecular metallogels (OGMs) was successfully constructed. Moreover, anion/amino acid responsive films based on supramolecular metallogels (OGMs) were prepared, which could be used as fluorescence anti-counterfeiting and encryption materials. Therefore, the supramolecular metallogels will be of great application value in the detection of anions and amino acids and as smart materials.