Silver Staining of SDS-PAGE Gels(Ⅰ)
1.Rinse gel on glass plate briefly with distilled water.
2.Wash gel in fresh 50% ETOH-12% HAc,with shaking,3 times,1 hour each.(Fix IEF gel ON in 10% TCA).
3.Wash gel four times with 10% ETOH-5% HAc for one hour each.One wash may be done overnight.
4.Rinse gel with several changes of water over five minutes.
5.Incubate gel in fresh 200 ml of 0.6 g K2CrO4 (0.0034 M)and 40 µl HNO3 (0.0032 M)for 5 minutes.
6.Rinse gel with several changes of water until color fades,approximately 10 min.
7.Incubate in 150 ml of 0.012 M AgNO3 (0.3 g/150 ml)Illuminated for 30 min,rocking several times to incorporate stain.
8.Rinse gel with three changes of water over 1 minute.
9.Rapidly rinse three times with 100 ml 0.28 M Na2CO3 and 0.5 ml 37% formaldehyde (8.9 g Na2CO3 and 1.5 ml formaldehyde/300 ml).Remove the darkened rinse solution quickly each time.
10.Agitate in 100 ml solution in 9 until desired intensity is reached and then stop development with 100 ml of 3% HAc.
11.Wash twice with water and store in water or in 10%MeOH-3% glycerol.Stain will not fade and can be photographed at your convenience.
Color Silver Stain
1.Fix gel in 50% ETOH and 10% HAc for 2 hours or more.
2.Wash gel in 50% ETOH and 10% HAc for 2 hours,then in 25% ETOH-10% HAc for 1 hour two times,and then in 10% ETOH-5% HAc for 1 hour twice.
3.Equilibrate gel in 0.012M AgNO3 solution (0.4 g/200 ml)for 2 hours.
4.Rinse with water for 10-20 seconds.
5.Reduce in the following solution for 10 min.: 200 ml 0.75N NaOH (6 g/200 ml)and dissolve 17.5 mg NaBH4 and 1.5 ml 37% Formaldehyde.
6.Wash gel in 0.75% Na2CO3 for 1 hour and store normally.Color will not fade and can be photographed at some time in the future.