TAGS™ In-Vivo Measurements
The TAGS device was designed to measure transdermal H2S to test the hypothesis that the diffusion rate (and therefore gas phase concentration) of H2S is directly proportional to dermal blood. Healthy volunteers between the ages of 21-65 were recruited. Exclusion criteria included subjects currently treated for hypertension, hyperlipidemia, and diabetes. Smokers and pregnant women were also excluded. 
It’s been demonstrated that there is a linear association between TAGS and LSCI when adjusting for age in the model (r=0.5717, p=0.0132 n=18). Interestingly, the TAGS device is not inferior to laser speckle contrast imaging (LSCI), considered as the gold standard, in healthy individuals using a non-inferiority margin of 5 (p=0.0394). The TAGS device has the potential, therefore, to serve as a more sensitive, economical, and easy to use diagnostic tool to detect H2S and predict dermal blood flow.