EIA detection of PCR products (streptoavidin capture)

[Jose Alejandro Palacios]

Hi everybody

I am trying to do detection of PCR products in microtiter plantes, it is 
a EIA-PCR system (all home made).
I have tryed coating IMULON 2 plates with streptoavidin 0.1 mg/well, 
usign one primer biotinilated, hydbirdization with a DIG labeled probe 
and developing with antiDIG-AP and dNPP substrate.

The problem is that everything is positive, 

Does somebody know methods for doign a good blocking posibly with sperm 
salm DNA?

Is the conc. of  Spreptoavidin to high?

I need help...

thanks

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Alejandro Palacios   informa at ns.casapres.go.cr
International Center for Medical Research and Training
LSU-ICMRT
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