New Perylene-Based Chemiluminescent Polymer Nanoparticles for Highly Selective Detection of the Superoxide Anion In...

The superoxide anion (O₂^•-) is one of the primary reactive oxygen species in biological systems. Developing a determination system for O₂^•- in vivo has attracted much attention thanks to its complex biological function. Herein, we proposed a new perylene-based chemiluminescence (CL) probe, the SH-PDI polymer, which was capable of generating strong CL signals with O₂^•- in comparison with other ROS. The CL mechanism involved was proposed to be a kind of oxidation reaction induced by the breakage of the S-S and S-H bonds into sulfoxide bonds by O₂^•-. Subsequently, a nanoprecipitation method was introduced, using cumene-terminated poly(styrene-co-maleic anhydride) as the amphiphilic agent, to obtain water-soluble nanoparticles, SPPS NPs, which exhibited not only stronger CL intensity but also higher selectivity toward O₂^•- than the SH-PDI polymer. Moreover, the CL wavelength of the SPPS-O₂^•- system was found to be located at 580 and 710 nm, which was conducive to CL imaging. By virtue of these advantages, SPPS NPs were utilized to evaluate the O₂^•- level in vitro in the range of 0.25-60 μM at pH 7.0, with a detection limit of 8.2 × 10^-8 M (S/N = 3). Moreover, SPPS NPs were also capable of imaging O₂^•- in an LPS-induced acute inflammation mice model and drug-induced acute kidney injury (AKI).