The Synthesis of Phenothiazine Derivatives with Mechanofluorochromism Property and the Fluorescence Detection for 2, 4, 6-trinitrophenol

Two phenothiazine derivatives (SPA and SPN) with significant aggregation-induced emission (AIE) characteristics were designed and synthesized. Photoluminescence spectroscopy showed that these two compounds could specifically recognize TNP in aqueous media. The fiuorescence of SPA was quenched by 89.1% in the presence of TNP with a detection limit as low as 8.62×10^-7 mol/L and a high Stern-Volmer quenching constant (K_sv) of 3.18×10⁴ L/mol. The fluorescence of SPN was quenched by 90.4% after addition of TNP with a detection limit as low as 5.00×10^-7 mol/L and a high Stern-Volmer quenching constant of 4.43×10⁴ L/mol. It indicated that SPA and SPN were expected to work as fiuorescent probe to detection TNP with high sensitivity and selectivity. Moreover, SPA showed reversible mechanofluorochromic properties. It was observed that SPA emitted strong blue fluorescence under 365 nm UV light and the color changed light yellow after grinding. So it can promisingly be applied to the fields of visual pressure sensors or anti-counterfeiting materials.