Investigation of Interaction of Bismarck Brown Y- Palladium Complex with AS1411 G-quadruplex Aptamer

Increased metabolic activity and metastasis are the main and most known characteristics of cancer cells. Increased activity of the cells results in an increase in the transcription, translation, and replication rate of DNA, hence the probability of the formation of G-quadruplex structures increases. The stabilization or destabilization of G-quadruplex with various ligands may cause disruptions in cell proliferation. So, stabilization or destabilization of these secondary structures is important cancer therapy approach. In the present study, Bismarck brown Y-Pd complex was formed in an easy, one-step mixing method. The spectral characteristics and stoichiometry of the BBY-Pd2 were investigated UV-Vis spectrophotometrically. The interaction of the BBY-Pd2 complex with the AS1411 G-quadruplex structure was investigated with spectrophotometric titration. The binding constants were found as 4.38 (± 1.96) × 104 M-1. The effect of the complex on the G-quadruplex conformation of AS1411 was investigated by using circular dichroism (CD) spectrophotometer. The existence of interactions was further supported by DNA polymerase stop assay using a high-sensitivity LED-induced fluorescence detector Qsep100 capillary gel electrophoresis system.