Novel self-assembled spirochiral nanofluorescent probe for fipronil detection efficiently by PET mechanism

A novel spirochiral compound S-SPINOL-Y1 (S-6,6'-bis (thiophen-2-yl)-2,2', 3,3'-tetrahydro-1,1'-spirobis[indinee]-7,7'-diol) was synthesized via a Suzuki reaction and self-assembled into nanospheres in ethanol solution. Nano or micron vesicles could be formed by changing the concentration of ethanol solvent. The resulting nanoprobe demonstrated rapid and effective recognition of fipronil (FIP) through the photoinduced electron transfer effect (PET mechanism), as evidenced by complete fluorescence quenching. Concurrently, the spiral chiral S-SPINOL-Y1 and FIP co-assembled into vein-like nanotubes within the ethanol solution by covalent bonding and intermolecular hydrogen bonding.