1. Soak the membrane in a large volume of deionized water for 30 minutes at room temperature to remove sodium azide.

2. Rinse thoroughly in deionized water.

Wet membranes should be stored in an aqueous preservative solution at 4^oC, but not frozen. Suitable preservatives are 0.1% sodium azide, 1% sodium benzoate, 1% hydrogen peroxide and 1% formaldehyde. They should not be allowed to dry out.

Regenerated Cellulose Membranes (dry membranes)

1. Soak the membrane in a large volume of deionized water for 30 minutes at room temperature to remove glycerine.

2. Rinse thoroughly in deionized water.

Unused dry membranes should be stored in a sealed plastic bag as a humidity control measure. They may be stored at room temperature or at 4^oC, but should never be frozen.

After they are wetted, the membranes should be stored in an aqueous preservative solution at 4^oC, but not frozen.

Suitable preservatives are 0.1% sodium azide, 1% sodium benzoate, 1% hydrogen peroxide and 1% formaldehyde. They should not be allowed to dry out.