Well, in that case I might be doing it with the school's spectrophotometer, it's a standard unit I've seen in most manuals, so I believe I'd be able to test the glycin.
Ascorbic acid seems to be a very useful reducing agent, in the color chem. section I posted my tests of making a color developer with CD1( I know, I know, but it's the only thing I've got, and time, I have some time on my hands ), and I've substituted hydroxylamine, which I am reluctant to purchase in the kg range, as it is offered here, with 500mg/l ascorbic acid, which seems to retard oxidation enough to make a reasonably stable developer. Anyhow, I digress