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sds-page running slowly - (Mar/24/2004 )

hi there,

when i run my protein through an sds-page, it takes almost 2 hours at 200V to run... i've checked my buffer conc is ok, so any ideas why it takes so long to run? dry.gif



are you running your gel in low temperature? e.g. 4C?


no, i'm running it at room temp


low amperage? 200V @ 1mA will take forever! smile.gif

maybe too high concentrated PA-gel for protein size? >100kDA proteins and >15% SDS-PA gels is a bad combination...



i use a 12% gel.... i've tried cltaering the amperage but it's never anywhere near as low as 1mA. running the gel at 240V takes 1 hour and 15 minutes now


The following affect SDS PAGE speeds-

1. A slow leak between the upper and lower reservoirs.
2. A strong sealant has been used at the lower end.
3. Buffer composition has been compromised - bad glycine or bad tris
4. Electode wire is damaged
5. The power supply has a wattage control that has been compromised
6. The gel is too thick
7. An acrylamide premix is being used in which bis quality has deteriroated
8. Water quality is bad due to a compromised deionizer- try a mixed bed resin treatment overnight.

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