FIGURE 5.

SPR sensorgrams of the interaction between the porphyrin TmPyP4 and different oligos (panels A, C, E, and G for poly(T), T10-loop, c-MYC, and G10-loop, respectively) and their corresponding Scatchard plots (panels B, D, F, and H). A, poly(T), from bottom to top of the panel [TmPyP4] = 1600, 800, 400, 200, 100, 50, and 25 nm. Experimental data are reported as dashed lines with circles (where the concentration was measured twice, also as dashed line with squares); best fit assuming a 1:1 interaction is reported as a solid line. B, poly(T), Scatchard plot, open circles are experimental data points and the solid line is the fit assuming a single binding site. C, T10-loop, from bottom to top of the panel [TmPyP4] = 1600, 800, 400, 200, 100, 50, and 25 nm. Symbols used are the same as in panel A. D, T10-loop, Scatchard plot, the continuous line represents the best fit according to 1:1 interaction model. E, c-MYC, from bottom to top of the panel [TmPyP4] = 1600, 800, 400, 200, 100, 50, 25, 12.5, 6.25, and 3.125 nm. Experimental data are reported as solid lines. F, c-MYC, concentrations used in the Scatchard plot are [TmPyP4] = 1600–25 nm. Open circles are experimental data points and the dashed line represents the best fit assuming a single binding site, whereas the solid line is the best fit assuming two independent binding sites. G, G10-loop, from bottom to top of the panel [TmPyP4] = 1600, 800, 400, 200, 100, 62.5, 31.25, 25, and 15.625 nm. Experimental data are reported as solid lines. H, G10-loop, the concentrations used in the Scatchard plot are [TmPyP4] = 1600–31.25 nm. Symbols used are the same as in panel F.