Levamisole is usually added to the substrate reagent, however there are
more ways.  A kit is the easy way to do this, Vector or DAKO, etc as just
two that work well.  Gut alk phos (murine) is blocked with 15% glacial
acetic acid for 5 minutes. There are a couple more ways, but these are very
easy to deal with.

 
Gayle Callis
Histopathology Supervisor
Veterinary Molecular Biology
Montana State University - Bozeman
Bozeman MT 59717-3610

406 994-6367
404 994-4303 (FAX)