PRO-F is a photoactivable H 2 S donor with ROS scavenging ability. PRO-F can be activated by light to produce fluorescent signal, for real-time tracking of released H 2 S. PRO-F activation doesn’t consume endogenous substances. deliver H 2 S in an intracellular environment to protect cells from excessive reactive oxygen species (ROS) induced damage. PRO-F shows enhancement on chronic wound healing, researched in diabetic models as well.