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Synthesis of materials for testing PAS

G.Patton

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This article is created as an additional material to an article about materials and methods of PAS (psychoactive substances) testing (Drugs testing reagents) and is intended for a wide range of readers.

Marquis reagent.
The Marquis reagent is obtained by adding of 50 ml of concentrated sulfuric acid (95-98%) to 10 ml of 37% formalin. Important notice: add sulfuric acid to formalin and not vice versa! It is also possible to use 40% formalin, but in this case you need to add 100 ml of concentrated sulfuric acid to 5 ml of 40% formalin. The obtained reagent has a transparent color, but eventually it will turn to the black one. The color of reagent does not affect the efficiency of solution.​

Mecke reagent.
The Mecke reagent is obtained by dissolution of 0,25 g of selenous acid (0,34 g of sodium selenite) in 25 ml of concentrated sulfuric acid (95-98%). Dissolution does not occur immediately and would take some time. The obtained reagent has a transparent color, but eventually it will turn to the black one.​

Mandelin reagent.
The Mandelin reagent is obtained by dissolution of 1 g of ammonium metavanadate in 100 ml of concentrated sulfuric acid (95-98%). The obtained reagent has an orange color, but eventually it will turn to the yellow one.​

Simon’s reagent (consists of two parts).
A: mixture of equal volumes of 1% sodium nitroprusside (water solution) and 10% acetaldehyde (water solution). Add 1 g of sodium nitroprusside in 100 ml of distilled water. Mix 10 ml of acetaldehyde with 90 ml of distilled water. Mix 10 ml (1:1) of each solution (sodium nitroprusside and acetaldehyde) and stir it thoroughly.
B: dissolve 2 g of sodium carbonate in 100 ml of distilled water (2% sodium carbonate solution). Add firstly one drop of A component, then one drop of B component to the examined sample.​

Ehrlich’s reagent.
The Ehrlich’s reagent is obtained by dissolution of 0,5-2 g of p-dimethylaminobenzaldehyde (p-DMAB) in 50 ml of 95% ethanol and 50 ml of concentrated hydrochloric acid (38%).​

Hofmann (Van Urk-Salkowski) reagent.
To a cool solution of 65 mL of H2SO4 (conc.) in 35 ml H20, add 0.125 g para-dimethylaminobenzaldehyde (p-DMAB), dissolve,add 1-2 drops of FeCl3 (9 g of FeCl3 in 100 mL H20).

Liebermann reagent.
It is composed of a mixture of potassium nitrite and concentrated sulfuric acid. 1 g Of potassium nitrite is used for every 10 mL of concentrated sulfuric acid. Potassium nitrite may also be substituted by sodium nitrite.​

Froehde Reagent.
100 ml Of hot, concentrated (95–98%) sulfuric acid add to 0.5 g of sodium molybdate or molybdic acid. 2–4 Hours must be allowed for the molybdate to dissolve.

Robadope Reagent.
The formulation of Simon's Reagent can be altered such that it gives a positive test with primary amines instead of secondary amines. The reagent is made up of two solutions, A and B, each of which is added to the sample being tested. Solution A: Dissolve 1 g of sodium nitroprusside in 50 mL of distilled H2O and add 2 mL of acetone to the solution. Solution B: 2% Na2CO3 in distilled water. Procedure: Add 1 volume of solution A to the sample, followed by 2 volumes of solution B.

Zimmermann reagent.
It is a two-component reagent, with the first component composed of 1,3-dinitrobenzene (1% w/v) in methanol and the second component composed of 15% potassium hydroxide in water. One drop of each component is added to the sample being tested and the resulting colour change is observed to give an indication of the identity of the compound.​
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Cocojamba

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Why are these reagents produced on such a small scale? Is it possible to enlarge them proportionally?
 

G.Patton

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Why are these reagents produced on such a small scale? Is it possible to enlarge them proportionally?
The fact is that some reagents usable for short time period (~7-10 days). After, you need prepare fresh ones.
 
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woohoo

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Where i can find tests database with compounds and drop colors?
 

ASheSChem

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Robadope Reagent.
The formulation of Simon's Reagent can be altered such that it gives a positive test with primary amines instead of secondary amines. The reagent is made up of two solutions, A and B, each of which is added to the sample being tested. Solution A: Dissolve 1 g of sodium nitroprusside in 50 mL of distilled H2O and add 2 mL of acetone to the solution. Solution B: 2% Na2CO3 in distilled water. Procedure: Add 1 volume of solution A to the sample, followed by 2 volumes of solution B.​
it's the Simon recipe; it is the same or an error?
 

G.Patton

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it's the Simon recipe; it is the same or an error?
Robadope is similar to Simon's reagent, replacing acetaldehyde with acetone. This variant is selective toward primary amines.
 
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