The carbon black particles of the India Ink may bind so tightly to proteins that
it won't come off under the conditions used for sequencing; kind of like binding
things to charcoal. Lee Olech suggests using 50% formic acid to elute the
proteins from the carbon.
Dale Richardson
Imaging Product Manager
Bio-Rad Labs
Subject: RE: PSQ-India ink stained samples
Author: "Chin David T." <ChinD@missouri.edu>
Date: 11/12/98 2:40 PM
Dan,
As I understand, India Ink is more sensitive than Commassie
staining. In my very limited experience with India Ink staining, it gave
the same result you got -- it gave much less signal then expected.
David Chin
UMC Protein Core
-----Original Message-----
From: Dan Brune [mailto:DBrune@asu.edu]
Sent: Thursday, November 12, 1998 12:25 PM
To: Recipients of ABRF List
Subject: PSQ-India ink stained samples
Dear Colleagues,
I recently have been given some samples to sequence that were on
PVDF blots stained with India ink, but have had little success in
sequencing them. The only exception was a very heavily stained control
band, but even that gave less sequencable protein than I expected from its
staining intensity. Two possible explanations for this come to mind,
namely (1) India ink causes partial blocking of proteins, and (2) India ink
staining is much more sensitive than Coomassie (which is usually used to
stain the PVDF blots that I receive), so that I am overestimating the
amount of protein present. Does anyone else have experience sequencing
proteins stained with India ink who might be willing to comment on these
possibliities?
Sincerely,
Dan Brune
Arizona State University