The RedoxSensor™ Green reagent included in the BacLight™ RedoxSensor™ Green Vitality Kit is an indicator of bacterial reductase activity. This reductase activity is, in turn, a reliable marker for changes in electron transport chain function and for changes in vitality that occurs following antibiotic treatment. RedoxSensor™ Green reagent penetrates both gram-positive and gram-negative bacteria. Following reduction, the RedoxSensor™ Green reagent will produce a stable green-fluorescent signal in 10 minutes that is compatible with formaldehyde fixation techniques.