Jinting Shang

Peroxynitrite (ONOO^-) is a quintessential reactive oxygen species (ROS) and reactive nitrogen species (RNS), renowned for its potent oxidizing and nitrifying capabilities. Under normal physiological conditions, a baseline level of ONOO^- is present within the body. However, its production escalates significantly in response to oxidative stress. ONOO^- is highly reactive with various biomolecules in vivo, particularly proteins, lipids, and nucleic acids, thereby playing a role in a spectrum of physiological and pathological processes, such as inflammation, cancer, neurodegenerative diseases, and cardiovascular diseases. Consequently, detecting ONOO^- in vivo is of paramount importance for understanding the etiology of various diseases and facilitating early diagnosis. Fluorescent probes have become a staple in the identification of biomolecules due to their ease of use, convenience, and superior sensitivity and specificity. This review highlights the recent advancements in the development of fluorescent probes for the detection of ONOO^- in diverse disease models and provides an in-depth examination of their design and application.

In this study, we present a novel near-infrared (NIR) fluorescent probe Nile-ONO designed for the selective and sensitive detection of ONOO⁻. The probe Nile-ONO employed Nile red as the fluorophore, with diphenylphosphinate serving as the reaction site. In the presence of ONOO⁻, the probe Nile-ONO exhibits remarkable fluorescence enhancement at 659 nm, with a response time of less than 20 min and a low detection limit of 0.32 µM. Importantly, MTT assays demonstrate low cytotoxicity in living cells. Furthermore, Nile-ONO has excellent imaging capabilities for endogenous ONOO⁻. Overall, this work introduces a valuable new method for the rapid detection of ONOO⁻ in biological systems.

Due to its favorable excited-state physicochemical properties, indium oxide (In₂O₃) has widely captured attention as a potentially great photocatalyst. However, an inferior charge separation efficiency limits its application. Recently, an increasing amount of evidence has demonstrated that the construction of surface defects is an effective strategy to boost photocatalytic performances. In this work, a ruthenium (Ru) species was successfully introduced into the lattice of In₂O₃ nanoparticles through co-precipitation and thermal treatment. It was found that the content of surface oxygen vacancies was directly related to the amount of Ru³⁺ doping, which further determines the separation efficiency of photogenerated carriers. As a result, the 0.5% Ru-In₂O₃ samples enriched with oxygen vacancies exhibit dramatically enhanced photocatalytic dehalogenation performances of decabromodiphenyl ether and hexabromobenzene, about four times higher than that of the pure In₂O₃ nanoparticles. This study emphasized the significance of the surface defects of the photocatalyst and may provide a valuable strategy to prepare highly active photocatalysts for photocatalytic dehalogenation reactions.