SDS-PAGE: unstained marker problem - (Feb/16/2007 )
Hi there,
I have been running 10% SDS-page gels using a biorad unstained marker which I was storing at -20 C. My marker used to show up quite well but the stain I was using was very old. So I ordered in new stain and now my protein samples are much clearer but the marker is no where to be seen. Could my marker have degraded? I have only had it for 1 month and always mix well when thawed.
Thanks everyone!
Do you usually aliquot your marker prior running a SDS PAGE? If you didnt, then it might be the marker. or perhaps not enough stain added to your marker? 
I have been running 10% SDS-page gels using a biorad unstained marker which I was storing at -20 C. My marker used to show up quite well but the stain I was using was very old. So I ordered in new stain and now my protein samples are much clearer but the marker is no where to be seen. Could my marker have degraded? I have only had it for 1 month and always mix well when thawed.
Thanks everyone!
how do you stain your protein gels? if CBB was used try silver staining to verify degradation or poor loading
I have been running 10% SDS-page gels using a biorad unstained marker which I was storing at -20 C. My marker used to show up quite well but the stain I was using was very old. So I ordered in new stain and now my protein samples are much clearer but the marker is no where to be seen. Could my marker have degraded? I have only had it for 1 month and always mix well when thawed.
Thanks everyone!
how do you stain your protein gels? if CBB was used try silver staining to verify degradation or poor loading
I had my marker in only 2 aliquots, I have now tried to use both to no avail. I use EZBlue stain from Biorad (a coomassie stain) Will try the silver stain, thanks!
Try to use other markers. Bio-Rads are soo expensive and there are so many other good ones, which will give you the same or even better results. I have used some from fermentas (but prestained) and peqlab, they were both great and cheap.