FIXATION FOR ISH

Fixative: 4% Paraformaldehyde in 70 mM Phosphate Buffer, pH 7.3.

Add fresh glutaraldehyde (EM grade) to the above fixative (10 ul to 5 ml). Final concentration 0.2%. Prepare prior to fixation.

Place fresh tissue into fixative. Cut into small pieces if very large. Fix at 4 C for 48 hr. Wash tissue pieces in cold, sterile PBS (to remove aldehydes which can interfere with hybridization). Change the solution 2-3 times/day for 3 days. Keep tissues at 4 C.

Embed tissue in paraffin.