Please have look at this:

https://www.thermofisher.com/au/en/home/life-science/protein-biology/protein-biology-learning-center/protein-biology-resource-library/pierce-protein-methods/protein-gel-stains.html

I use the following protocol:

1. Place the gel in a solution [30% ethanol, 10% acetic acid] for 30 min***.

2. Remove the previous solution and add a solution [0.5% glutaraldehyde, 0.1% sodium thiosulfate, 30% ethanol, 0.4M sodium acetate pH 6], for 15 min.

3. Remove the previous solution and perform 5 washes to the gel with distilled water, for 5 min each.

4. Remove the water and place the gel in a solution [0.1% silver nitrate, 0.025% formaldehyde (67.57 microL of formaldehyde 37 wt.%, for 100 ml solution)], for 20 min.

5. Remove the silver solution, and put and remove at the time, a solution [2.5% sodium carbonate, 0.1% formaldehyde]. (For this solution, prepare 250 ml).

6. Put again the carbonate solution until bands in the gel appear, controlling the developing to stop the reaction before the gel burnt.

7. Stop the reaction adding a solution 5% acetic acid.

8. Let the gel in distilled water.

***

When you suspect that determined proteins could be eluted from the gel, the first step can be replaced by this fixer solution [3.5 % sulfosalicylic acid, 11.5% trichloroacetic acid (TCA)], for 30 min.

Then, remove solution and perform 4 washes the gel with distilled water for 5 min each, and continue the protocol in the step number 2.

Just guessing: "silver staining of WHAT? " ( Leong Chee Yan has not said anything about the used technique)...

NB: Edit 28th DEC. 2020: another use of silver staining -in addition to staining proteins and/or nucleic acids (DNA, RNA) on (polyacrylamide) gels certainly is histological/ histochemical staining of sectioned tissue specimens (brain, GIT, etc). That is why I thought it would be of benefit for all to know about the nature of the method/technique used / in question.

https://conductscience.com/silver-staining-protocol/

Dear Leong Chee Yan

1.fix the gel in 30 ml distilled water+ 30 ml acetone+0.75 ml TCA +25 micro litres of formaldehyde for 5 min on a rocker.

2.wash with 60 ml of distilled water for 5 min on a rocker.

3.then 30 ml distilled water+ 30 ml acetonefor 5 min on a rocker.

4. crucial step add 100 micro litre of 10 % sodium thio sulphate to 60 ml of distilled water, 1 min on a rocker.

5.then wash with 60 ml of distilled water for 2 min on a rocker.

6.60 ml of distilled water + 0.8 ml of 20 % silver nitrate +0.6 ml of formaldehyde for 8 minutes on rocker.

7.wash with 60 ml of distilled water for 1 min on a rocker.

8. prepare developing solution by mixing 60 ml of distilled water +1.2 grams of sodium carbonate + 25 micro litre of formaldehyde+ 25 micro litre of 10% sodium thio sulphate. develop slowly until you get clear bands generally 1 to 2 minutes.

9. stopper solution : stop the reaction with 60 ml of distilled water + 0.6 ml of glacial acetic acid for 5 minutes on rocker

10. rinse with 60 ml of distilled water and go for imaging or store the gel.

Hope this protocol is useful for you and all the very best for your experiment..

Unfortunately our young colleague, Leong Chee Yan either is not willing to respond, or has left his position and the ResearchGate account is / has been abandoned.

This is the succus of Googe-search for

"Destaining / Staining solution for silver staining...",

Just for another interested colleague with a similar problem I would like to cite the following:

Found, e.g., at:

https://www.bio-rad.com/webroot/web/pdf/lsr/literature/LIT34.pdf,

(this is a Bio-Rad.com SOP/Manual -Technical Data Sheet for a Silver-Staining Kit. Emphases / bold or Italics mine)

"Destaining solution for silver stain

Silver staining is not recommended for agarose gels.

Completely destain the Coomassie stained gel in 40% methanol/10% acetic acid. Begin at step 2 of the silver staining protocol and proceed as usual. Fix the gel in 30% methanol/10% trichloroacetic acid/3.5% sulfosalicylic acid for 1 hour."

and further

(within the pdf, p.-2-, p.-3-).:

" 3.6 Destaining

Gels allowed to develop too long will have high background or surface deposits of silver (mirroring).

Destaining can be performed using a photographic reducer [*#) see bottom] such as the following, which was developed by Switzer, et al.3

• Dissolve 37 g of sodium chloride and 37 g of cupric sulfate anhydrous in 850ml of deionized water.
• Add concentrated ammonium hydroxide until the precipitate that forms is completely dissolved to give a deep blue solution.
• Adjust to 1 liter with deionized water.
• Prepare a second solution containing 436 g sodium thiosulfate pentahydrate in 1 liter deionized water.
• Prepare the destain by combining equal parts of the two solutions immediately prior to use.
• Remove the gel from the destain before complete destaining has occurred.
• Wash several times in deionized water to remove the destain and prevent fogging. Stop the destaining process with 10% acetic acid for 15 minutes.
• Wash the gel for at least 1 hour with several changes of water.
• To restain, begin with step 8, Table 1.

An alternative destain is Kodak rapid fix, solution A.

• Add 12 ml of rapid fix to 88 ml deionized water to prepare the destain.
• Stop the destaining process with 2.4 g Kodak hypo clearing agent dissolved in 100 ml deionized water, for 15 minutes.
• Wash the gel for at least 1 hour with several changes of water.
• To restain, begin with step 8, Table 1.

Ref:

3. Switzer, R. C., Merril, C. R. and Shifrin, S., “A Highly Sensitive Silver Stain forDetecting Proteins and Peptides in Polyacrylamide Gels,” Anal. Biochem., 98, 231(1979).

*#) or search for "Farmer's solution (also a photographic reducer)

e.g.:

• https://www.freepatentsonline.com/y2005/0230255.html (CTRL*F: insert | Farmer |, & return)

also cf:

• https://www.researchgate.net/post/What-is-the-best-way-to-dissolve-silver-stained-1D-PAGE-band-in-order-to-subject-it-to-LC-MS,
• https://www.researchgate.net/post/Repeating_silver_staining_on_same_gel
• http://www.proteomicswiki.com/wiki/index.php/Destaining_Silver-Stained_Spots,
• https://www.chem.ufl.edu/wp-content/uploads/sites/17/2014/05/SDS-PAGE-Stain-Protocol.pdf (destaining Coomassie stain)
• https://patents.google.com/patent/WO2002079771A1/en ( Hydrogen Peroxide Silver Stain Removal )
• http://www.protocol-online.org/biology-forums-2/posts/7116.html

and NOT the least/last one (perhaps interesting for basic reading):

• 'Silver staining of proteins in polyacrylamide gels: a general overview' by Thierry Rabilloud*, Laurent Vuillard+ , Claudine Gilly and Jean Jacques Lawrence, 1994 (2009) = (can be found as a "manuscript" in ResearchGate Archives, cf.:

• Article Rabilloud T, Vuillard L, Gilly C, Lawrence JJSilver-staining...

  Article Silver-staining of proteins in polyacrylamide gels: A general overview

and additional readings:

Article Silver staining of proteins in Polyacrylamide gels

Article Modified silver staining for immobilized pH gradients

Chapter Silver Staining of 2-D Electrophoresis Gels

Article Mechanisms of protein silver staining in polyacrylamide gels...

Article Improvement and simplification of low-background silver stai...