[Histonet] DAB black/brown

[Boor Peter]

Can anybody help?
 
For our IH we're using DAB with Ni chloride to get black color (especially
for double stains with AEC). 
In the last period however we get also brown coloured stainings and even in
one run we get some slides with brown some with black color (very bad for
our double stains).
We used new DAB, made fresh Ni chloride solution and H2O2 but nothing helped
till now...we now even got some slides stained half black half brown...
This is especially bad for our double stainings (it's very hard to
distinguish brown from red).
 
Where could be the problem? 
 
Thanks a lot for any suggestions!
 
Peter Boor
 

Peter Boor

University Clinic of Aachen, Dept. of Nephrology and Immunology, Pauwelsstr.
30;  52074 Aachen; Germany   

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