FIG 7 .

Addition of magnesium chloride to the Rd 13 aptamer enhances G-qudruplex folding (A), but addition of posazonazole alone does not (B). This is seen in an increase in the maximum at 260 nm and a decrease in the minimum at 240 nm. Both Rd 13 and Rd 9 exhibit G-quadruplex structure in 0.2 mM magnesium chloride salt (C). The structure changes drastically in the presence of magnesium chloride and 100 μM posaconazole (D). The Rd 13 Scrambled aptamer does not change, but Rd 9 now contains a peak of 230 nm and a minimum at 280 nm and Rd 13 contains two peaks at 230 nm and 260 nm with a new minimum peak above 300 nm.