How to prevent polyacrylamide gels from leaking while casting

Summary: use a viscous polyvinylpyrrolidone (PVP) solution as a sealant

How this works

• This is meant for those who cast there own polyacrylamide gels with glass plates. In our lab’s experience these often leak while casting due to chips in the glass plates.
• A viscous PVP solution seals any gaps.
• PVP is water soluble. It is not so soluble that it will wash away during casting, but a stream of water will remove it.
• Other water soluble polymers that form viscous solutions will likely also work.

Instructions

• Make a 33% solution of PVP in water by weight. (330mg PVP and 670uL water). Stir and let it sit for a day to totally dissolve. It should be viscous.
• The PVP I used had an avg MW of 360,000
• Assemble the glass plates as usual
• Apply a drop of PVP with a toothpick or pipette tip to the bottom corners where the two plates meet
• Put the glass plate on the rubber seal and add the acrylamide solution as normal