Self-assembly of A Rosin-Based Stimuli-Responsive AIE Amphiphile for Multi-level Encryption, and Ultrasensitive Detection of 4-Nitrophenol

Stimuli-responsive aggregation-induced emission (AIE) materials that enable dynamic emission control and adaptive applications in dynamic information encryption and advanced anti-counterfeiting via external stimuli have attracted considerable attention. A bio-based AIE amphiphile ( CSMPANa ) was synthesized by integrating maleopimaric acid (MPA) with a α-cyanostilbene, which exhibited typical AIE characteristic and obvious solvatochromism. Importantly, the fluorescence emission of CSMPANa showed dual stimuli-responsiveness. Adding alkali caused the cyano group turned into an amide, red-shifting the fluorescence emission. Subsequent adding acid resulted in a blueshift. Furthermore, 365 nm UV light induced a [2+2] cycloaddition to form a dimer, leading to a redshift. The obvious solvatochromism and dual stimuli-responsiveness of CSMPANa were exploited for multi-level information encryption. AIE wormlike micelles were further prepared by mixing CSMPANa and cetyltrimethylammonium bromide (CTAB). The viscoelasticity and optical physical properties of CSMPANa /CTAB wormlike micelles could be modulated by varying its concentration, pH, or UV light irradiation. Additionally, the system exhibited selective recognition to 4-Nitrophenol in aqueous media with high anti-interference capability, enabling ultrasensitive visual detection (LOD = 17.29 μM). Density functional theory (DFT) calculations elucidated the sensing mechanism, revealing that the specific recognition originates from the synergistic effect of the strongest binding affinity and minimized steric hindrance of the 4-NP para-isomer. This work developed a system that is not solely dependent on organic solvents and possesses dual responsiveness.