TICT-ICT state change mechanism based acetate fluorescent sensor act as an 'Off-On-Off' switch and logic gate

摘要

A novel sensor LX based on the TICT-ICT state change mechanism has been designed and synthesized. The sensor LX can perform as not only an exclusive-NOR(XNOR) logic gate but also an "Off-On-Off" molecular switch triggered by AcO~- and H~+ ions. By selectivity binding with Y-shape AcO~- via double hydrogen bonds, the sensor LX underwent a TICT-ICT state change and induced a dramatic fluorescent response. However, the addition of H~+ results in the fluorescence decreasing of LX-AcO~-. This "Off-On-Off" switch could be controlled via AcO~- and H~+ cyclically. Moreover, the sensor LX could instantly detect AcO~- in non-aqueous and aqueous solution (water content ≤ 10%) with specific selectivity and high sensitivity, these sense procedures could not interfered by other coexistent competitive anions (F~-, Cl~-, Br~-, I~-, AcO~-, H_2PO_4~-, HSO_4~-, ClO_4~-, CN~-, S~(2-), HSO_3~-, citrate). The detection limits was 4.0 × 10~7 M of AcO~-, which is quite low for the detection of AcO~- ions found in many chemical and biological systems.