Beta-Gal staining in primary neurons

Fix cells w/ 4 ml fix soln/10cm or 60 cm dish, 37 C, 5 min

 Fix soln.:     for 100 ml (use w/i 1 wk) 
   5.4 ml 37 % formaldehyde (Final 2%)
   800 ul 25% Glutaraldehyde (fin. 0.2%)
   94.5 ml PBS

 Stain soln.:  part a. 5 mM Potassium Ferricyamide (K3Fe(CN)6)
       5 mM potassium ferrocyamide (K4Fe(CN)6.3H2O)
       2 mM MgCl2
  in PBS. Store @ R.T., use w/i 1 month or until see ppt.

   For 200 ml of a. : 0.33 g K3Fe(CN)6
      0.42 g K4Fe(CN)6.3H2O
      0.4 ml 1M MgCl2

   Part b. X-gal (5-bromo-4-chloro-3-indolyl-beta-gal)
     40 mg/ml in DMSO
 
 Heat part a & b to 37 C
 Add part b to part a to final 1 mg/ml X-gal. Add part b slowly while mixing, or crystals will form. 
        Filter to remove crystals.