Fig. (4). Ratiometric reduction of the signal output data.

The specific signal at 665 nm may be affected by light transmission. The ratio (i.e. 665nm/620 nm) will normalize the signal measured and generate a variable that is independent of the optical properties of the medium in which the interaction is studied. In the case shown above, the 665 nm fluorescence decreases proportionally to the transmission, whereas the ratio corrects this interference and is equivalent in both situations.