Novel fluorescent cationic benzothiazole dye that responds to G-quadruplex aptamer as a novel K+ sensor

A fluorescent cationic benzothiazole dye that selectively targets a G-quadruplex aptamer was designed and synthesized as a K+ sensor. The K+-driven aptamer sensor is based on the strategy of conformational transition from single-stranded DNA to G-quadruplex structure, leading to an amplified fluorescence signal in the reporter. This fluorescent sensor displayed high selectivity for K+, suggesting great potential for practical applications.