At the end of last week my HPLC data was not looking so great. Instead of the nice straight baseline I wanted I had a very messy baseline. So on Monday we tried to figure out what was wrong by rerunning part of my samples I had tried to run the week before. This did not work and my base line was still messy. Next we had the flush the column and that took a long time. Then we switched out the phosphate buffer I made and put the old one back on. This seemed to fix things until we run the mello yellow. We think there was something in the mello yellow that messed up the baseline. So mostly my week has been flushing the HPLC column with water and methanol to try and clean the column. On friday I ran a standard and the baselines were almost perfect. After that I tried running two caffeine standards, but the baselines were very messy.