Fluorescent switch constructed based on hemin-sensitive anionic conjugated polymer and its applications in...

Here, a fluorescent switch is constructed combining hemin, hemin aptamer, and a newly synthesized anionic conjugated polymer (ACP), poly(9,9-bis(6'-phosphatehexyl) fluorenealt-1,4-phenylene) sodium salt (PFHPNa/PFP). In the "off-state", the fluorescence of PFP is sensitively quenched by hemin, with a high K(sv) value of approximately 10(7). While in the "on-state", the formation of the aptamer/hemin complex recovers the fluorescence intensity. The fluorescent switch is sensitive and selective to hemin. To testify the universality and practicality of the fluorescent switch, a series of label-free DNA-related sensing platforms are developed, containing three DNA sensing strategies and one ATP recognition strategy. The fluorescent switch developed is simple, sensitive, and universal, which extends applications of the anionic conjugated polymers.