Donna,
We coat our own slides and purchase Poly-L-lysine from Sigma. The dilution is 
1:10, I believe.  We use these slides for our special stains. For IHC we use 
charged slides. Have never tried the Poly-L-lysine for the IHC. For every 
liter of solution, you can coat 900 slides. Reply with any questions you 
might have.

Jeanne Godine
Pathology Consultants
Lynchburg, VA