Bio-Rad Silver Stains - Manual (Page 3)

Section 1
Introduction
Silver staining is a highly sensitive method for detecting proteins and nucleic
acids in polyacrylamide slab gels. The Bio-Rad Silver Stain, derived from the
method of Merril,1 is 10-50 fold more sensitive than Coomassie brilliant blue
R-250 for proteins (detection is ~0.1 ng/mm2) and 2-5 fold more sensitive than ethid-
ium bromide for single and double stranded DNA and RNA. Approximately 24 full
size gels or 48 mini gels can be stained with one kit.
Section 2
Silver Stain Kit Components
Oxidizer Concentrate - A 10-fold stock solution. Contains potassium dichro-
mate (CAS 7778-50-9) and nitric acid. Store at 4 ˚C.
Warning: Strong oxidizer - avoid contact with reducing agents.
Irritant - avoid contact with skin and eyes. Wear gloves and eye pro-
tection.
Silver Reagent Concentrate - a 10-fold stock solution. Contains silver nitrate
(CAS 7761-88-8). This solution is heat sensitive. Store at 4 ˚C.
Warning: Poisonous - caustic to eyes, skin, and mucous membranes. Wear
gloves and eye protection.
Developer - Four packages of dry chemical blend. Contains sodium carbonate and
paraformaldehyde (CAS 30525-89-4). Store at 4 ˚C.
Warning: Poisonous
Irritant - vapor and dust irritates eyes, mucous membranes, and skin.
Wear gloves, lab coat, and eye protection. Fume hood recommended.
Section 3
Important Procedural Information
Read the entire protocol, procedural information, and the Troubleshooting
Guide before beginning.
3.1 Water Purity
Deionized water of less than 1 µmho conductivity is recommended for all phas-
es of the procedure. Contaminants such as chloride ions will precipitate silver
ions causing reduced sensitivity and increased background. Water suspected of
containing interfering ions can be thoroughly deionized by passage over a column
of AG
® 501-X8(D) mixed bed ion exchange resin (catalog number 142-6452).
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