BT FIX

4.0 ml 10% paraformaldehyde
5.0 ml 2x fix buffer

Adjust pH to 7.3 if necessary. Add dH2O to a final volume of 10.0 ml. Final concentration is 4% paraformaldehyde, 0.15 mM CaCl2, 4% sucrose in 0.1 M PO4 buffe