I am working as a summer research student at a lab right now. I tried to use acetonitrile: methanol (50:50) mixture and also acetonitrile (100) to extract 5-Fluorouracil, uracil, dihydrouracil. I centrifuged the samples and took the supernatant which I then dried down to reconstitute in 0.1% Formic acid as I am using formic acid as my mobile phase. But my reconstituted solution is cloudy, so it might clog my column in the LC-MS/MS