Remove filters from the petri dishes with flat-end tweezers, lifting from one edge and rolling the filter off the agar. Avoid tearing filter and lifting agar from the surface. Chilled plates help to avoid the latter problem. Place filter in base solution for 1 minute, agar side up. Blot filters on dry Whatman 3MM or gel blot paper to remove excess base.
Transfer filters to neutralizing solution for two minutes.
No moisture should be on the glass oven window. It takes about 2 hours for the large filters and an hour for the small filters. After baking, nitrocellulose membranes are very fragile. Before hybridization, wet filters briefly in 2x SSPE and stack filters on top of one another. Allow excess solution to drip from the filters and transfer to Kapak bags.