Development of rare-earth upconversion luminescent nanoprobe for bisulfate sensing and imaging of drug-induced hepatotoxicity

Abnormal levels of bisulfite in living organisms may cause respiratory diseases, cardiovascular diseases and even cancer. Rare-earth upconversion luminescent nanomaterials have anti-Stokes luminescence characteristics, excellent photostability and high chemical stability, while organic fluorescent probe has the advantages of the specific recognition groups. Thus, the combination of luminescent nanomaterials and an organic fluorescent probe can offer a novel approach to detect the content of HSO₃⁻. A NIR-excited nanoprobe (UCNP@PEG@HAM) was developed by assembling HSO₃⁻-sensitive dye (HAM) on the surface of upconversion nanoparticles (UCNP) with the assistance of DSPE-PEG₂₀₀₀-NH₂. Upon being excited by light at 980 nm, UCNP@PEG@HAM could achieve upconversion luminescence response to HSO₃⁻ and has the advantages of short response time, high sensitivity (LOD = 0.652 μM) and good selectivity. It could be used not only in vitro applications, but also in fluorescence imaging in mouse liver injury and the remediation models. The nanoprobe can monitor liver injury in living animals using near-infrared excitation. Furthermore, the nanoprobe could be a simple strategy to quickly check whether synthetic drugs can cause liver damage.