During RNA extraction of larval stage nematodes, upon addition of isopropanol the solution turned yellow and after centrifuging, the pellet was yellow too. After washing with 75% EtOh the yellow pellet remained the same colour and even dissolved as yellow in H2O. I think it must be the isopropanol. The 260/280 values were ok but the 260/230 values were very very low making me think the isopropanol retained salts or something with the pellet. Any idea why this is and if there's anything I can do to fix it?