I’m working on the separation of two polar compounds. I’ve been reading up on reversed phase chromatography and just trying to understand one aspect. In an online guide from Waters I read (
https://www.waters.com/webassets/cms/library/docs/wa20756.pdf):
“To retain polar compounds on this non polar surface we reduce the amount of organic in the mobile phase (i.e., 100% water).”
I’m confused because by doing that you’re making the mobile phase even more polar….wouldn’t that make it a better solvent for a polar molecule!? Then why would that cause a polar molecule to bind the nonpolar stationary phase?? What am I missing?
Thanks!