Columns were used to purify RFP (red) expressing plasmid. Columns were recycled as per the recycling protocol (left) or not (right) and then used to purify AmilCP (blue) expressing plasmid. The elutant was transformed and plated. Recycled columns resulted in 100% AmilCP (blue) producing colonies. Non-recycled columns produced ~ 50% AmilCP (blue) producing colonies and ~50% RFP producing colonies resulted from contaminating plasmid from the previous purification. Recycling works.