Clean-up for Ethidium Bromide

Caution: EtBr is a powerful mutagen and is moderately toxic. Wear gloves when working.

When EtBr conc. is >0.5 mg/ml:

1.Add sufficient water to reduce the concentration of EtBr to <0.5 mg/ml.

2.Add 1 volume of 0.5 M KMnO₄. Mix, add 1 volume of 2.5 N HCl (210 ml HCl in 1 L water) .

Mix and allow the solution to stand for several hr at room temperature.

3.Add 1 volume of 2.5 N NaOH (100 g NaOH in 1 L water). Mix, and discard the solution.

When EtBr conc. is  >0.5 µg/ml:

* electrophoresis buffer contains 0.5 µg/ml EtBr

1.Add 29 g Amberlite XAD-16 (Rohm and Hass) for 1 L of solution.

2.Store the solution for 12 hr at room temperature, shaking it intermittently.

3.Filter the solution through a Whatman No. 1 filter, and discard the filtrate.

4.Seal the filter and Amberlite resin in a plastic bag, and dispose of the bag in the hazardous waste.