You say poe-TAY-toe & I say bud-AY-da -- is it glycin or glycine?

[xkaes]

I know a lot of people say or write glycin when they really mean glycine. Is that the case here? At least they didn't just write "pyro".

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DiXactol Ultra (type) Developer Stock Solution A Sodium Sulphite 3 g Glycin 2 g Pyrocatechin 10 g Phenidone 0.2 g Sodium Metabisulphite 5 g Water to 100 ml Stock Solution B Sodium Hydroxide 10 g Distilled water to make 100 ml ​ To make a standard working solution, mix 1 part A with 1 part B with 100 parts water. ​

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[koraks]

I know a lot of people say or write glycin when they really mean glycine. Is that the case here?

No, I think it's meant to be "glycin" here, i.e. the photographically active developer. Not the amino acid 'glycine.'

 

[Don_ih]

Glycine is, far as I know, never present in any film or paper developers.

Glycin, however, is pretty useful, if only for extending the life of developers. Seems to do a great job of that.

 

[melanger]

N-(4-hydroxyphenyl)glycine. See https://en.wikipedia.org/wiki/Glycin.

 

[xkaes]

I figured that was the case. I just wanted to be sure.

 

[DREW WILEY]

Glycine is an amino acid, one of the four which comprises a DNA chain, for example. No relation to the developing agent glycin.

 

[GLS]

Glycine is an amino acid, one of the four which comprises a DNA chain, for example. No relation to the developing agent glycin.

Nucleic acids do not contain amino acids. They contain nucleobases, triplet sets of which code for a specific amino acid once read.

 

[Doremus Scudder]

Adenine (A), guanine (G), thymine (T), and cytosine (C) are the four nitrogenous bases that make up the building blocks of DNA, also known as nucleotides.

Glycine is a nutrient amino acid that your body uses to build proteins. It is not contained in DNA or RNA.

Glycin (not to be confused with glycine) is a photographic developing agent.

Doremus

 

[DREW WILEY]

My slip of memory. Sorry. Still, the same basic distinction from a film developing agent.

 

[Don_ih]

My slip of memory.

Don't you know you're supposed to consult Wikipedia before you say anything?

 

[DREW WILEY]

Well, it's an awfully bad slip of memory for someone who got a Biology degree 54 years ago. That was mostly field biology, plus a lot of microbiology, and back then Genetics was about the boring breeding of fruit flies. My younger wife did work in a modern Biotech R&D quality control position for six years specializing in DNA and protein purification. This neighborhood is the world epicenter of all that Pharmaceutical stuff; and I can hardly even untangle all the acronyms which the University now has for its many tech-oriented "Biology" degrees. Whatever happened to catching badgers and dragonflies and newts? Well, that is still going on too; but they want DNA samples, especially to confirm that the isolated populations are still viable.

 

[Doremus Scudder]

No worries, Drew! I confuse glycine and guanine all the time Guanine makes a horrible developer.

 

[DREW WILEY]

Like I said, I was looking for a career in wildlife biology. Guanine is the fertilizer bats drop onto cave floors. Glycin is what nitroglycin explosive is made of, or something like that. My darkroom hasn't blown up yet, however. I have stepped in bat guano, which does have a color resembling terribly oxidized old glycin. Only Wickipedia knows the truth.

 

[David Lindquist]

Not to be confused with glycerol, glycerine or glycerin which are all, in fact, the same thing.

Unlike, say, sodium sulfite, sodium sulfide or sodium sulfate,,,

My academic background was similar to Drew's (and I'm guessing at the same university, maybe 4 years earlier.) So the chemistry I had helped in fathoming the photographic process. Didn't include Physical Chemistry or "P-Chem" as my chem major school mates in Bowles Hall called it.

David
Cal, class of 66, a bad year to run out your student deferment

 

[GLS]

Redundancy is a common problem with trivial names for compounds. A necessary evil much of the time though, as systematic names quickly become unwieldy for even moderately complex molecules.