Hypochlorous acid triggered fluorescent probes for in situ imaging of a psoriasis model.

Psoriasis is a common skin disease with complex pathogenesis that lacks diagnostic methods. Typically, psoriasis is an inflammation-related disease accompanied by high expression of reactive oxygen species (ROS) in the infected part. However, due to the lack of suitable tools, it is difficult to identify the ROS, especially certain types of ROS (e.g., HOCl) in the psoriasis model. Here, two HOCl-specific fluorescent probes, G1 and G2, were designed and synthesized based on oxazine 1. Both probes could react with HOCl with high selectivity among other ROS under physiological conditions. The selected probe G2 could detect HOCl in HL-60 cells without special stimulation and detect endogenously produced HOCl in the mouse model of arthritis. Thus, G2 was used to identify and image HOCl in situ in the imiquimod induced psoriasis model. The result showed that HOCl was a potential pathological marker of psoriasis.