Path: utzoo!utgpu!water!watmath!uunet!ig!bionet-20.bio.net!GORDON.BRADSHAW
From: GORDON.BRADSHAW@BIONET-20.BIO.NET (Toby Bradshaw)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: Uniform gels for reading long sequences
Message-ID: <12412697193.39.GORDON.BRADSHAW@BIONET-20.ARPA>
Date: 8 Jul 88 16:22:08 GMT
References: <12412284971.17.EROSENTHAL@BIONET-20.ARPA>
Sender: daemon@presto.ig.com
Lines: 13

Eric:

The blur you see at 300-400 bases is due to an anion formed by the glycerol in
the Sequenase enzyme when electrophoresed in a buffer containing borate ions.
This anion migrates at that position in the gel, screwing up the resolution.
I don't normally care about it, but if you do, I would suggest trying a
buffer other than Tris-borate or (probably too much trouble) a spin column
or precipitation to eliminate the glycerol.  As for the wedge gels, a longer
fixing time will help since its the failure to remove the hygroscopic urea that
makes gels stick to film.  Hope this helps.

Toby Bradshaw
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