Understanding the likely source of contamination is important to determine the type of cleaning solution that may be required. Often, it is sufficient to simply flush the column sequentially with water, isopropanol (propan-2-ol), and then water. Washing should be performed at a reduced flow rate with a minimum of 20 column volumes per solvent. Flushing the column with water containing a chaotropic salt (to disrupt protein structure) may be beneficial, but should be followed with a water wash