Promega Gel Purification Kit
Posted 30 January 2005 - 11:32 PM
I have tried to spin the column in a higher speed and more time, but still, there is ethanol residues there...
Did anyone have the same problem?
Posted 31 January 2005 - 02:08 AM
I use this kit all the time. To ensure the column is dry I usually centrifuge at maximum speed for at least five minutes to dry the column after the second ethanol wash, I remove the wash fromt he wash tube and then spin again for 2 minutes at maximum speed.
I have had this problem before when the DNA sample floats out of the well upon loading adding this extra step by removing the wash and then centrifuging again makes things better.
Posted 31 January 2005 - 02:17 AM
its very important to do an extra spin step to your collumn after the the wash step - throw away the flow-through, and spin the collumn, dry, for another minute.
Posted 31 January 2005 - 02:20 AM
i use this kit and after the last centrifugation, i make an additionnal 5' top speed centrifuge and let the column dry RT 30' or 37°C 10' (98°F). I use to make 30' RT due to the fact for miniprep purification (promega kit) drying at 37°C reduce the elution efficiency.
hope being little useful
Good luck !