Why is my GSH concentration greater than my Total GSH concentration? Why is my calculated GSH/TGSH ratio greater than 1?

There are several possible reasons for this kind of result. For example, it could be that there is no statistically significant difference between the [GSH] and the [TGSH], indicative of little to no GSSG in the sample. If such is the case, the GSH concentration may very well be greater than the Total GSH concentration due to experimental bias. Another possible explanation is due to assay activity loss which may lead to inconsistent assay results. The assay components are unstable at room temperature and when exposured to light and should be used within two hours of preparation. For a kit with enhanced stability, we recommend using Amplite® Rapid Fluorimetric Glutathione GSH/GSSG Ratio Assay Kit *Green Fluorescence*.