ARA-299 Cloudy After Reconstitution + SLU-PP-332 Solubility Questions

cjdilan

cjdilan

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Hoping to hear from folks who have hands-on experience with these two.

I used 2 mL of bacteriostatic water for each reconstitution.

ARA-299 (vial on the left): the result was milky/cloudy. After leaving it overnight it got a bit better, but it still isn't clear. There are no big particles — just a general haziness throughout.

SLU-PP-332 (vial on the right): at first there was some haze/settling, but at this point it looks nearly completely clear and remains clear with gentle swirling. Possibly one tiny speck, but nothing you'd call obvious.





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Questions:

Regarding ARA-299:

Is it normal to stay cloudy like this when using BAC?

Has anyone gotten a better outcome by switching to PBS or some other buffer?

How do you decide when a vial is bad versus simply dissolving slowly?

Regarding SLU-PP-332:

I realize it isn't very water-soluble — when it looks "clear in BAC," does that actually indicate proper dissolution, or is it merely suspended?

For those using it injectable rather than oral — which solvent system do you use?

General:

Do you all give it 24–48 hrs before making a call on clarity?

Are there any tricks other than dilution that genuinely help (without resorting to sketchy solvents)?

This way proofed by AI
 
As far as I understand it, SLU isn't water-soluble at all — it's a strongly polar molecule, which means lipids, DMSO and similar solvents are the only things that will take it up. To my knowledge there's no established safe route for getting it into a human injection, since DMSO itself isn't considered safe to swallow or inject. In water I'd guess it turns cloudy, though it's possible the suspension is simply too fine for the eye to catch; the mannitol, which is the filler normally used, would go into solution without any trouble, and the SLU is present in such minuscule quantities that this could be why no cloudiness shows. ChatGPT may be able to offer something, though it could also decline if it reads the question as a request for self-dosing guidance. Would injecting it subcutaneously as a suspension work? Possibly, if it were mixed thoroughly enough — but that isn't a standard practice. My assumption is that it would be taken up by the subcutaneous tissue, which I'd expect to have solubility properties better suited to polar compounds than water does, though I can't state that with certainty. I'm definitely not recommending it. From what I've read in the research, 5mg is probably a placebo-level dose regardless, judging by mouse dosing of 50mg/kg/dose. That may actually be for the best, since the compound isn't studied or understood well enough to be ready for human trials. If it ever clears at least phase 1 testing in humans, it would be worth revisiting, because the effects seen in rodents do sound interesting.

I haven't checked what the solubility of ara-290 is.
 
cjdilan said:


I think that you know the answer for the cloudy vial. Not for human consumption. The SLU-pp-332 I think that you know the answer to that as well. Just about everything that I've read or seen says not to inject it. Oral seems the way to go. It's so much easier as well.

Click to expand...
Click to expand...
 
cjdilan said:

Hoping to hear from folks who have hands-on experience with these two.

I used 2 mL of bacteriostatic water for each reconstitution.

ARA-299 (vial on the left): the result was milky/cloudy. After leaving it overnight it got a bit better, but it still isn't clear. There are no big particles — just a general haziness throughout.

SLU-PP-332 (vial on the right): at first there was some haze/settling, but at this point it looks nearly completely clear and remains clear with gentle swirling. Possibly one tiny speck, but nothing you'd call obvious.





View attachment 11812

Questions:

Regarding ARA-299:

Is it normal to stay cloudy like this when using BAC?

Has anyone gotten a better outcome by switching to PBS or some other buffer?

How do you decide when a vial is bad versus simply dissolving slowly?

Regarding SLU-PP-332:

I realize it isn't very water-soluble — when it looks "clear in BAC," does that actually indicate proper dissolution, or is it merely suspended?

For those using it injectable rather than oral — which solvent system do you use?

General:

Do you all give it 24–48 hrs before making a call on clarity?

Are there any tricks other than dilution that genuinely help (without resorting to sketchy solvents)?

This way proofed by AI
Click to expand...

The pH in your ARA-290 is incorrect. Introduce a bit of acetic acid to bring the pH into range, and the cloudiness will disappear.
 
cjdilan said:

Hoping to hear from folks who have hands-on experience with these two.

I used 2 mL of bacteriostatic water for each reconstitution.

ARA-299 (vial on the left): the result was milky/cloudy. After leaving it overnight it got a bit better, but it still isn't clear. There are no big particles — just a general haziness throughout.

SLU-PP-332 (vial on the right): at first there was some haze/settling, but at this point it looks nearly completely clear and remains clear with gentle swirling. Possibly one tiny speck, but nothing you'd call obvious.





View attachment 11812

Questions:

Regarding ARA-299:

Is it normal to stay cloudy like this when using BAC?

Has anyone gotten a better outcome by switching to PBS or some other buffer?

How do you decide when a vial is bad versus simply dissolving slowly?

Regarding SLU-PP-332:

I realize it isn't very water-soluble — when it looks "clear in BAC," does that actually indicate proper dissolution, or is it merely suspended?

For those using it injectable rather than oral — which solvent system do you use?

General:

Do you all give it 24–48 hrs before making a call on clarity?

Are there any tricks other than dilution that genuinely help (without resorting to sketchy solvents)?

This way proofed by AI
Click to expand...
My method: 0.5ml of PBS goes into the ARA290 first and I wait for it to dissolve, and only after that do I add 1.0ml BAC.
 
I've been researching this too. As a precaution, I went ahead and ordered Phosphate Buffered Saline. So far my vendor says nobody has complained about reconstitution, so perhaps plain Hospira will work? It's hard to tell — I haven't reconstituted it yet. I might also pick up A.A. just to be safe.
 
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