Glycin stock solution

[mjbovee]

I just mixed up a batch of Ansco 130 and noticed that my glycin is starting to brown a bit (it's about 3 months old, for what it's worth, and has a light beige color). I still have more than 70g left of my current batch, but I understand the shelf life of dry glycin is only around 3-6 months. I don't anticipate going through 70g in the next few months and would hate to have to throw it away; I was wondering if it'd be possible to extend its shelf life by mixing it into a stock solution with some water and sodium sulfite, or something like this?

 

[GregY]

when i buy 130 that i won't use immediately, i store the glycin in the freezer and only take it out when i''m going to mix the developer

 

[bnxvs]

Hello!
First of all, glycine-photo does not lose its activity much longer than 6 months. Some batches of glycine I have stored for more than 3 years. Unless, of course, the glycine was originally pure enough. In this case, the color can be up to a rich coffee color.
Secondly, there is a method to recover and purify oxidized glycine-photo. This method is known from an old USSR patent. If you briefly outline its essence, pure glycine-photo can be isolated from an aqueous solution by adding SO2 or bisulfite (metabisulfite), followed by washing the resulting precipitate with bisulfite solution.
Such glycine-photo is stored for a very long time.
I think that in Albuquerque, with your deep tradition of "home chemistry" (judging from what we saw in "Breaking bad") it would not be difficult to do such operations to purify glycine.

 

[Alan9940]

Like GregY, I have a stock of glycin that has been in the freezer for years with no discoloring.

 

[juan]

I’ve got some mahogany brown glycin that still works. Don Cardwell (where is he?) used to say that glycin aging was an Internet myth.

 

[Alan Johnson]

Glycin Solubility

I've read that Glycin is sparingly soluble in plain water but is readily soluble in alkaline or acidic solutions. Can a liter of 1% solution of Sodium Metabisulphite be used to dissolve 10 or more grams of Glycin? Would such a solution preserve Glycin for a year or more? What's your recipe for...

www.photrio.com

Some methods of preserving glycin here.
However the solvents will likely affect the pH of some working solutions.

 

[mjbovee]

Thanks for the insight everybody. I'll try putting my glycin in an airtight container and throwing it in my garage fridge.

 

[john_s]

Thanks for the insight everybody. I'll try putting my glycin in an airtight container and throwing it in my garage fridge.

freezer if you have it the garage. Otherwise I'd use the house freezer, adequately labelled!