We load samples for 64 wells in every third well, and then run in, etc., and
have experienced no problems. Loading like this can be done with an
8-channel multipipettor with good success. It takes a little extra time to
work out your sample sheet, but you get used to it fairly quickly.
We have also found that using Flowgen's Longranger gel solution gives better
results (wrt resolution) than standard 19:1 or 29:1 Acrylamide gels.
Regards
Andrew
_______________________________________________________________
ASTRA CHARNWOOD
Molecular Biology, Bakewell Road, Loughborough, Leics, ENGLAND LE11 5RH
Tel: +44 (0)1509 644213 Mobile: +44 (0)778 8595040 Fax: +44 (0)1509
645557
andrew.walding@charnwood.gb.astra.com
> ----------
> From: Dieter Deforce[SMTP:Dieter.Deforce@rug.ac.be]
> Sent: 07 April 1999 07:17
> To: Recipients of ABRF List
> Subject: Re: Odd lanes on 377XL
>
> Hello,
>
> 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 *
> *************************************************************
> * Homepage: http://allserv.rug.ac.be/~evdeeckh *
> *************************************************************
>