Does the problem occur in the first loaded of the odd samples? It seems to
me that there is too much time between the loading of the first series of
samples and the starting of the actual run it that time the first loaded
samples experience diffusion in the gel which of course couses broader
bands. So I think the solution here is working faster or using a loading system.
Greetings,
Dieter
>We are currently running 64 lanes on each of two ABI 377XL's and are
>experiencing a rather odd migration problem with the odd numbered samples.
>As most 377 users do, we load the odd lanes first and, after a 5 min.
>prerun, finish with the evens and start the normal electrophoresis
>conditions of a 2X run. On a whole, when we look at the data the next day,
>the odd lanes appear to have less delineated peaks and, once in a while,
>have bands that are so "fuzzy" in the fist 100bp, that we are forced to
>reload the sample. We have found no correlation with the reagents(i.e.
>template and primer) used in these lanes, however, we are consistently
>having three or four of these sample results a day. We have attempted
>modifying cleanup protocols using several different types of columns, and
>have varied the time in which we run the first load in before loading the
>even lanes, but, so far, have seen no improvement. I have attached a JPEG
>file showing the differences in the electropherograms from samples that are
>run on the same gel. Has anyone experienced the same problem or is this
>isolated to our lab? I would much appreciate any suggestions on
>troubleshooting. Thanks.
>
> -Brian Coullahan
*************************************************************
* Dr.Apr. Dieter Deforce *
* Lab Pharmaceutical Biotechnology *
* Harelbekestraat 72 *
* FFW-RUG *
* University of Gent *
* 9000 Ghent *
* E-mail : Dieter.Deforce@rug.ac.be *
* Tel : +32 9 264.80.62 *
* Fax : +32 9 220.66.88 *
* Belgium *
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* Homepage: http://allserv.rug.ac.be/~evdeeckh *
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