Evaluation of 2',7'-Dichlorodihydrofluorescein Diacetate and Dihydrorhodamine 123 for the Detection of Reactive Oxygen Species

Abstract

Exposure to reactive oxygen species (ROS) has been linked to many diseases and is one of the mechanisms suggested for the adverse effects of inhaling airborne particulate matter. The ability to detect and quantify these species collectively could contribute to a better understanding of the mechanisms and the prevention of possible adverse health effects. However, the use of oxidant-sensitive fluorescent probes for ROS detection has been problematic with respect to a reliable, easy-to-use, and related to health outcomes. In the present study, the performance of the commonly used probe 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) for ROS detection in ambient air was compared to a popular probe used in cell culture research, namely dihydrorhodamine 123 (DHR-123). DCFH-DA and DHR-123 were tested with several surrogate compounds from different functional ROS groups (e.g., hydroperoxide and organic peroxide) and a few non-ROS groups. For ROS detection in ambient air, DCFH-DA was often more suitable because it responded to most ROS functional groups. Furthermore, it did not react with many non-ROS. DHR-123, on the other hand, reacted with more species including those that are not oxidizing, and may lead to an overestimation of the ROS present. These results illustrate the species that trigger positive responses from the two probes and could thus be used to understand the mechanisms of these reactions and to decide which probe to choose for ROS detection under different circumstances.