Silver Stain (Audi 5000 effect/All at once)

[rhubner at molbiol.ox.ac.uk]

Hi there,
 I used the kit four times with nr. 3 displaying the Audi 5000 effect! I
imagined that I had some dirt in one solution or on the glass... 
 Thanks for pointing out where exactly this effect comes from! Long live the
Net ;-)
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In article <CoH753.5rw at ncifcrf.gov>, pnh at fcs260c2.ncifcrf.gov (Paul N Hengen) writes:
> 18 April 1994
> Connie Rickey
> Bio-Rad Laboratories
> E-mail: crickey at haley.genetics.bio-rad.com
> 
> Dear Connie:
> 
> This week I had an unfortunate experience with a kit I purchased from Bio-Rad.
> I was using the Silver Stain Plus Kit (Cat. No. 161-0449) for staining proteins
> within a polyacrylamide gel.  I followed the procedure outlined in the
> instructions and encountered a problem with STEP 3. Staining and Developing
> Step.
> 
> In the protocol, it is written:
> 
> "While stirring rapidly, add 50 ml of the Development Accelerator Reagent
> to the beaker."
> 
> Since I didn't know that I should add the entire 50 ml of solution at once to
> avoid a milky white precipitate, I added it slowly by pipeting. When I saw some
> precipitates form, I slowed down the pipetting which made matters worse.  I've
> designated this the "Audi 5000 effect" as applying the brake only accelerates
> the precipitation (That's a JOKE!!! ONLY A JOKE!!!) :-)
> 
> My gel was absolutely ruined by the staining solution when it precipitated.
> I called Bio-Rad technical services and found out the problem is in the
> writing of the protocol.  The addition of the three words "all at once" would
> have saved me a week of work and some precious materials. It would be nice if
> Bio-Rad were to correct the wording of this so others are not trapped as I
> was.
> 
> I'm also posting this letter so that others will not make the same mistake.
> 
> Thank You.
> 
> -Paul.
> 
> *******************************************************************************
> * Paul N. Hengen, Ph.D.                           /--------------------------/*
> * National Cancer Institute                       |Internet: pnh at ncifcrf.gov |*
> * Laboratory of Mathematical Biology              |   Phone: (301) 846-5581  |*
> * Frederick Cancer Research and Development Center|     FAX: (301) 846-5598  |*
> * Frederick, Maryland 21702-1201 USA              /--------------------------/*
> *******************************************************************************