What makes old Adoflo go cloudy?

[koraks]

Note that this question is really out of curiosity; I'm not trying to solve a problem.

I've got this old (definitely very expired) bottle of Adoflo of which I decanted a bit into a pipette bottle. As you can see, it is quite cloudy, whereas fresh Adoflo is as clear as water:

The SDS for this product lists the following components:

There may be other stuff in there that doesn't require listing, like IDK, plain ethylene or propylene glycol or so?

I wonder what has decomposed or perhaps polymerized here. Again, just curious. I've seen something similar happen with dishwasher rinse agent if you use that in warm water; it tends to go milky in a very similar way.

 

[Rudeofus]

Note that this question is really out of curiosity; I'm not trying to solve a problem.

I've got this old (definitely very expired) bottle of Adoflo of which I decanted a bit into a pipette bottle. As you can see, it is quite cloudy, whereas fresh Adoflo is as clear as water:

View attachment 397831

The SDS for this product lists the following components:
View attachment 397832
There may be other stuff in there that doesn't require listing, like IDK, plain ethylene or propylene glycol or so?

I wonder what has decomposed or perhaps polymerized here. Again, just curious. I've seen something similar happen with dishwasher rinse agent if you use that in warm water; it tends to go milky in a very similar way.

The first compound (also known under the name Triton X-100 appears to degrade into some non-polar and therefore water insoluble compounds. This article's abstract suggests a few degradation pathes.

 

[koraks]

Thanks; that's interesting. I may have to dig up the fulltext on that. The abstract is kind of brief on the actual pathways.

 

[Samu]

I don't know. but I have noticed the same with Kodak's Photo Flo, which I use for my black & white films.

 

[koraks]

Oh, I always believed Kodak Photo Flo was super stable, but I guess it's not necessarily.

 

[Alessandro Serrao]

Note that this question is really out of curiosity; I'm not trying to solve a problem.

I've got this old (definitely very expired) bottle of Adoflo of which I decanted a bit into a pipette bottle. As you can see, it is quite cloudy, whereas fresh Adoflo is as clear as water:

View attachment 397831

The SDS for this product lists the following components:
View attachment 397832
There may be other stuff in there that doesn't require listing, like IDK, plain ethylene or propylene glycol or so?

I wonder what has decomposed or perhaps polymerized here. Again, just curious. I've seen something similar happen with dishwasher rinse agent if you use that in warm water; it tends to go milky in a very similar way.

Probably bacterial growth.

 

[koraks]

Probably bacterial growth.

Probably not; that tends to be stringy and uneven, and tends to settle on the bottom. This is perfectly dispersed, resulting in a stable, milky suspension. Moreover, Adoflo contains a pretty effective biocide as you can see in post #1 (Kathon). See @Rudeofus' post above; that one makes good sense.

 

[Alessandro Serrao]

Probably not; that tends to be stringy and uneven, and tends to settle on the bottom. This is perfectly dispersed, resulting in a stable, milky suspension. Moreover, Adoflo contains a pretty effective biocide as you can see in post #1 (Kathon). See @Rudeofus' post above; that one makes good sense.

You cannot tell just from a single photo. Maybe the bottle has been shaken before and the bubbles has settled. Who knows?
I've had some Adoflo go bad in the past and the bottle just looked like that.
Contrary of what's been spoken here and there, even wetting agents hves a shelf life and inf fact the op says "I've got this old (definitely very expired) bottle of Adoflo"

 

[koraks]

Who knows?

I do. It's my bottle, after all. I know what happened to it from the moment I decanted some AdoFlo into it up to present. It's sitting right behind me in the chemistry cupboard.

I've had some Adoflo go bad in the past and the bottle just looked like that.

Sure. No doubt the bottle this came from (if I still have it somewhere) contains some that has gone bad in the same way. The question is what the pathway of degradation is - again, out of curiosity.

 

[Alessandro Serrao]

I do. It's my bottle, after all. I know what happened to it from the moment I decanted some AdoFlo into it up to present. It's sitting right behind me in the chemistry cupboard.


Sure. No doubt the bottle this came from (if I still have it somewhere) contains some that has gone bad in the same way. The question is what the pathway of degradation is - again, out of curiosity.

Il looks line bacterial growth to me. You should plate it in a petri dish with some minimum agar medium. Make sure it's all sterile.

 

[koraks]

Il looks line bacterial growth to me.

I don't think so. There's also no bacterial smell. And no, I'm not going to incubate it, for lack of interest. We'll just have to disagree on what it is.

 

[BrianShaw]

Does it still work?

 

[Alessandro Serrao]

I don't think so. There's also no bacterial smell. And no, I'm not going to incubate it, for lack of interest. We'll just have to disagree on what it is.

Bacterial smell? LOL

 

[koraks]

Does it still work?

It appears so, yes, although I have the impression it's less effective than it once was.

Bacterial smell? LOL

Yes, "LOL", this is exactly the reason why we evolved a sense of smell to begin with.
Look, I'd appreciate it if you got out of this thread. Thanks.