Some of the bands in my filter do not have a straight line compared to other bands even if they all are the same proteins. What can be wrong? One end of the band seemed to move faster than the the other end.

Thanks for any ideas!

few things to consider:
the same volume for all the samples
cleaning your wells before loading
and when loading try to load into the middle of the wells

check the platinum wire in the gel running apparatus
(consider replacing the platinum wire)
do you have a homogenous electric field?

fill the empty slots with 1x sample buffer

does it slope only on one side (from one side to the other) or do you get a "smile"?

hi
there are so many factors 1.leaving the wells blank, try to fill the empty wells with the loading buffer try to avoid the LAST wells and load sample buffer same volume in that wells
2. try to run the gel in recommended volts dont choose higher voltage
3.use fresh gels dont use stored gels for PAGE
4.blott long time for low voltage

Dear User, I hope you might be getting proper bands by now , if not till now, then kindly scan the image and attach here, it will be easier to detect the accurate problem what you might be having.
Wishes