Thiol-SiOx nanodot-based fluorescent probes for the detection of trace hydrogen peroxide

Hydrogen peroxide (H₂O₂) is one type of reactive oxygen species (ROS) that can lead to a variety of forms of oxidative stress damage in human beings. Numerous methods have been used to detect H₂O₂ concentrations in various environments, however, these often suffer from inadequate detection limits, instrumental complexity, and multi-step experimental design, which may render them unfeasible for the required application. Herein, we report on a novel method for H₂O₂ detection that utilizes thiol-based SiOx nanodots (S-SiOx NDs) to initiate a sol-gel phase transition which can be observed by naked eye. This approach could lead to a very simple, rapid, and low cost method for H₂O₂ detection down to 5.8 μM, which is lower than the FDA regulation for H₂O₂ in food packaging. Furthermore, using a PL spectrometer allows H₂O₂ detection down to 0.01 μM. This S-SiOx NP system allows researchers the flexibility to choose between rapid visible detection of H₂O₂, or very high sensitivity detection by PL spectrometry. (paper)