Fig. 3.

Fluorescence analysis of Rhein-DNA interactions.

(a) Intrinsic fluorescence emission spectra of Rhein (50 μM) at an excitation of 400 nm in the presence of various concentrations (A-K represent 0, 25, 75, 150, 200, 350, 500, 550, 650, 700 and 800 μM respectively) of DNA and L (red dotted line) represents emission spectra of 100 μM DNA alone excited at 400 nm, (b) Stern-Volmer plot for quenching of Rhein by DNA, (c) Modified Stern-Volmer plot for quenching of Rhein by DNA