Purity - GBL turns into an acid in long-term?

[MrTommyGun]

Hello guys! My uncle used to think he knows everything about GHB, GBL and their chemistry, metabolism whatsoever. However, recently he got really surprised. A few months ago he had come to an idea that the best way of storage and daily usage of GBL is diluting it with water 1:5 and storing it in a glass bottle. He usually measured the required amount of the solution into a cup of juice using a medical dosing cup with 5 ml scaling. Well, everything went smoothly until the point my uncle got out of juice one day and tried to mix his 1:5 GBL solution with a glass of water. It tasted surprisingly acidic. For a purely controlled experiment, he compared this solution with the solution of the same proportion prepared from pure GBL. The tastes were awesomely different. The fresh solution 1:100 had a taste partially astringent with a solid "pepper" flavor. A 1:100 solution prepared by diluting 1:5 solution twentyfold tasted greatly astringent and seriously acidic, but almost completely lacked "pepper". At the same time, the physiological actions were almost the same or barely noticeable.
Ladies and gentlemen, here is the question: what happened to GBL in a 1:5 solution over a span of about one month? Did it convert to GHB-COOH? Or partially to succinic acid? Or semialdehyde? Or?

MrTommyGun added 1389 Minutes and 10 Seconds later...

upd: pH=7

[Quantum Dude]

Gammabutyrolactone (GBL) is a tricky substance. If diluted as an aqueous solution (especially if distilled water is used) it will slowly form an equilibrium with gamma-hydroxybutyric acid (GHB), see scheme provided. This is actually the reaction that occurs in the stomach when GBL is ingested. Therefore, it explains the acidic taste of the stored GBL aqueous solution. It simply contains a GBL/GHB mixture.

Swim is strongly opposed to the method of storage, the best one is to generate the conjugated salt (such as the sodium salt) of GHB by hydrolysis of GBL with a strong base. The powder should be stored within a vacuum sealed container, in a dark and dry environment.

Reputation Comments on this post:

Superb job, as ever.

[MrTommyGun]

Thx dude! Swiy wouldn't have to explain that in such a detailed way, because Swim is a chemist and pharmacologist. However, it is still doubtful whether it is an acid, because pH is equally 7.

[Quantum Dude]

What was the method of pH measurment ? According to this study [1]:

the form that predominates depends on the pH of the matrix. GHB predominates when the pH is made >4.72, while GBL predominates when the pH is made <4.72. This is often taken advantage of when analyzing various matrices for either GHB or GBL. Complete conversion to GBL is favored in dehydrating conditions at pH’s below
2.0 in a concentrated acid solution.

[1]http://www.drugs-forum.com/forum/loc...atid=1&id=6336



Also not sure what is the difference between succinic acid and GHB-COOH that swiy was referring to, arent they the same but just defined diferently ? Besides, this theory should be discarded as well if pH is completely neutral.

[MrTommyGun]

Under GHB-COOH swim meant GHB itself, GHB-acid))
The method of measurement was indicator paper.
It seems that the shift from pure GBL-water to a final mixture system takes two-three days under room temperature. During these days the pepper is reducing and the astringency is growing. The experiment is easy to set up in controlled conditions