Fig. 7.
a Intensity weighted mean fluorescence lifetimes of Coumarin 6 and Coumarin 307 solutions and comparison with values expected from theory. Data of pure solutions were fitted to a single exponential decay model, while data of mixture solutions were fitted to double exponential decay models. The total number of photons detected was approximately 2,000,000 in the cuvette based system and 350,000 in the low-cost system. b Fluorescence lifetimes extracted from Coumarin 6 and Coumarin 307 measured with both instruments. Dashed lines represent the expected fluorescence lifetimes the pure compounds in ethanol (τC6 = 2.5 ns; τC307 = 5.3 ns). c Relative proportion calculated for Coumarin 6 (a1/(a1 + a2)) from the fitting results