https://www.selleckchem.com/products/PI-103.html 
  Combining electrospray ionization mass spectrometry (ESI-MS) with circular dichroism (CD) spectroscopy, a G-rich sequence from miR-92a promoter region was discovered to form a parallel G-quadruplex structures in KCl or NH4OAc solution. In case of high concentration of NH4OAc, the ESI mass spectra showed peaks of a dimeric G-quadruplex structure with 4 ammonium ions. Meanwhile, palmatine, a natural alkaloid, was screened by ESI-MS to bind with the miR-92a G-quadruplex affinitively. The variable temperature experiment of CD also proved tha
 
					 
						 
                                     
				    				