Synthesis of an amphiphilic "turn-on" fluorescent probe for detection of ClO- and photodynamic therapy

Hypochlorite (ClO-) is a powerful oxidant that can react with many biomolecules and plays important roles in various diseases. Selective and sensitive detection of ClO- in living organisms is therefore of great significance and various fluorescent probes have been developed recently. However, the poor water solubility and aggregation caused quenching effect of conventional fluorescent probes have largely restricted their applications in living organisms. In this work, we reported the design and synthesis of an amphiphilic "turn -on" fluorescent probe (named as TPAMP-HCCP-PEG) via conjugating of TPAMP and amino group terminated PEG using hexachlorocyclotriphosphazene (HCCP) as the linkage. The results demonstrated that TPAMP-HCCP-PEG can self -assemble into nanoscale particles with excellent water dispersibility and desirable biocompatibility. TPAMPHCCP-PEG can serve as "turn -on" fluorescent probe for selective and sensitive turn -on detection of ClO- with limit of detection (0.23 mu M). The sensing mechanism is possibly relied on the oxidization of C--C in TPAMP to form TPA-CHO. Moreover, on account of the donor-acceptor (D -A) structure, TPAMP-HCCP-PEG can also be used as the photosensitizer for cancer cell photodynamic therapy.