NON-RADIOACTIVE INSITU Metaphasepretreatment?

[pallderdice at kean.ucs.mun.ca]

We have been treating metaphase spreads on microscope slides with 2XSSC at 
37 degrees C. for 30-60 min and then through alcohol series prior to 
denaturing and insitu hybridization with biotin-labelled DNA probes.  We 
are interested in tryng other pretreatments.  ONCOR stopped recommending 
proteinase treatment.  - other suggestions? the probe we want to see is 1.
(1.5kb).