HyPer is the genetically encoded biosensor of intracellular hydrogen peroxide (H2O2), the most stable of the reactive oxygen species (ROS) generated by living cells. HyPer has a high sensitivity and specificity for detecting intracellular H2O2 by confocal laser microscopy. However, it was not known whether high speed ratiometric imaging of H2O2 by HyPer is possible. We thus investigated the sensitivity of HyPer in detecting changes to the intracellular H2O2 levels in HEK293 and PC12 cells using a microfluorometer imaging system. Increase in the HyPer ratio were clearly evident on stimulations of more than 100 μM H2O2 and fast changes in the HyPer ratio were observed on ratiometric fluorescent images after H2O2 treatment. These results suggest that HyPer is a potent biosensor of the fast temporal production of intracellular H2O2.

• Yu-Mi Yang(Department of Oral Biology, BK21 PLUS Project, Yonsei University College of Dentistry)
• Sung Jun Lee(Department of Oral Biology, BK21 PLUS Project, Yonsei University College of Dentistry)
• Dong Min Shin(Department of Oral Biology, BK21 PLUS Project, Yonsei University College of Dentistry) Correspondence