G-Quadruplex Stabilization and Fluorescence Detection

BRACO-19, PDS and TMPyP4 powders were purchased from Sigma, MedChemExpress and TCI, respectively. The compounds were diluted in 10 mM Tris HCl (pH = 7.4) and 100 mM KCl buffer. The sequences of G-quadruplex and G-mut were listed in Table 2. Synthetic RNA oligonucleotides in powder were diluted to 2 μM final concentration in 10 mM Tris HCl (pH = 7.4) and 100 mM KCl buffer, heated at 95°C for 5 min and slowly cooling down to room temperature. The RNA solution was incubated at 4°C overnight in the absence or presence of compounds. ThT powder was bought from Aladdin Industrial Corporation. Oligonucleotides and ThT were mixed at 1:0.5 M ratio to a final concentration of 1 and 0.5 μM, respectively. Fluorescence emission was recorded at 495 nm after excitation at 425 nm using a TECAN SPARK microplate reader (30 (link)).