How can staining from the DPD reagent be removed from plastic sample tubes or cells?
Cleaning stained plasticware
Pink stained viewing tubes or sample cells can be cleaned with hot water and a detergent such as Liquinox or Alconox. If the stain persists, it is best to get new tubes and prevent staining by rinsing immediately after using the DPD reagents. Acid or alcohols may cause the plastic to turn white.