Dansyl chloride, which absorbs maximally at 330 nm and fluoresces maximally at 510 nm, can be used

Question:

Dansyl chloride, which absorbs maximally at 330 nm and fluoresces maximally at 510 nm, can be used to label amino acids in fluorescence microscopy and FRET studies. Tabulated below is the variation of the fluorescence intensity of an aqueous solution of dansyl chloride with time after excitation by a short laser pulse (with Io the initial fluorescence intensity).

10.0 15.0 20.0 Tins 5.0 IfIO 0.11 0.05 0.45 0.21