Reagent tests to differentiate GHB, GBL, GHV and 1,4-butanediol (14B)

[Aetherius Rimor]

According to "Clarke's Analysis of Drug's and Poisons" there are four methods for detecting GHB and tests 1 through 3 three detect GBL with a different result. Will these give a false positive with GHV or 14B; and are there any reagents capable of performing a colorimetric assay capable of identifying GHV and 1,4-butanediol and differentiating a substance between the four. A multi-step test to identify with a higher degree of accuracy isn't problem if necessary (such as identifying MDxx then using Simon's to differentiate between MDMA and MDA).

I'm finding very little information with regards to reagent testing for the presence of GHB vs an analog to begin with; and struck gold with this book. However finding information on GHV/14B and their responses to the reagents has been so difficult. Here is what I have, quoted from the above book.

Colour test 1

Reagent
Mix chlorophenol red and modified Schweppes reagent in a 3 : 1 ratio.

Method
Place 0.5mL of a liquid sample in a test tube. Adjust to pH 5–8 with
0.01 mol/L sodium hydroxide. Add 2 drops of the test reagent and swirl.
An immediate colour change (orange–red to dark red) indicates GHB.
GBL gives a yellow colour.

Colour test 2

Reagent
Mix bromocresol purple and bromothymol blue in a 1 : 1 ratio and mix
the combined reagent with modified Schweppes reagent in a 7 : 1 ratio.

Method
Same procedure as for colour test 1. GHB gives a purple colour and GBL
gives a yellow colour.

Colour test 3

Reagent
Mix bromocresol green and methyl orange in a 1 : 1 ratio and mix the
combined reagent with modified Schweppes reagent in a 3 : 1 ratio.

Method
Adjust the pH of the test solution to neutral if necessary and add 2 drops
of test reagent. A dark-green colour indicates GHB; GBL gives a yellow–
orange colour.

Colour test 4

Reagent
1% cobalt nitrate solution.

Method
Place 0.5mL of a liquid sample in a test tube. Add a few drops of the test
reagent. A pink-to-violet colour indicates GHB.

AS

 

[Solipsis]

In this thread the quoted directions seem to be a bit more clear:
http://www.bluelight.org/vb/threads/246588-Does-ghb-have-any-reaction

But still from the same book.

When I read your post I thought: never mind colour test 4, not sure if it is coincidence it seems to be omitted in the linked thread.

Schweppe and chlorophenol basically just detect typical organic acids I think. Apparently it is used in studies, if you have those chemicals I'd use that.
The other ones are just variations, but with different color trends depending on pH changes.

I think it should work fine on detecting GHV which is also an organic acid.

As far as I can tell differentiating 1,4-BDO from the other ones involves checking for alcohols but excluding the acids. GHB and GHV may test positive for acids and alcohols but 1,4-BDO only for alcohols.

 

[sekio]

Gas chromatography, my friend!

If you have the pure substances at hand or even an aqueous solution, then melting point is an easy way to differentiate BDO from others. Heat the solution to 100C for a while to ensure it's not mixed with water, then see where the residue melts.

I would imagine any test for GBL would also detect GVL.

 

[Floydsnicklefritz]

According to "Clarke's Analysis of Drug's and Poisons" there are four methods for detecting GHB and tests 1 through 3 three detect GBL with a different result. Will these give a false positive with GHV or 14B; and are there any reagents capable of performing a colorimetric assay capable of identifying GHV and 1,4-butanediol and differentiating a substance between the four. A multi-step test to identify with a higher degree of accuracy isn't problem if necessary (such as identifying MDxx then using Simon's to differentiate between MDMA and MDA).

I'm finding very little information with regards to reagent testing for the presence of GHB vs an analog to begin with; and struck gold with this book. However finding information on GHV/14B and their responses to the reagents has been so difficult. Here is what I have, quoted from the above book.

AS

I am not going to ask, but I can't imagine why you'd want to do that.