"Turn-on" fluorescent sensor for oleanolic acid based on o-phenyl-bridged bis-tetraphenylimidazole.

Fluorescent sensors had been extensively applied on sensing various biomolecules effectively, but no fluorescent sensor for oleanolic acid was presented up to now. In this work, the first fluorescent sensor for oleanolic acid was designed and synthesized based on o-phenyl-bridged bis-tetraphenylimidazole (PTPI). PTPI was prepared by bridging two tetraphenylimidazole units and o-phenylenediamine via Schiff-base condensation in yield of 86%.

An effective fluorescent sensor for ClO in aqueous media based on thiophene-cyanostilbene Schiff-base.

Although some reports on sensing ClO had been presented, the ClO sensor with high selectivity and sensitivity in aqueous media was still expected. Herein, an effective fluorescent sensor for ClO in aqueous media was designed and synthesized by simple procedure based on cyanostilbene derivative (TCS). TCS exhibited strong fluorescence in aqueous media, which could be selectively quenched by ClO among various species.