The Mandelin reagent is used as a simple spot-test to presumptively identify alkaloids as well as other compounds. It is composed of a mixture of ammonium metavanadate and concentrated sulfuric acid. Its primary use is for the detection of ketamine and PMA[1] Unlike the most common reagent test chemicals, it has a deep red colour that changes to yellow if there is no alkaloid, which occurs within about 48 hours of mixing.[2]
The United States Department of Justice method for producing the reagent is the addition of 100 mL of concentrated (95–98%) sulfuric acid to 0.5[3] -1 g of ammonium metavanadate.[4]
This reagent was invented by the German pharmacologist, Karl Friedrich Mandelin (1854 - 1906) at the University of Dorpat.
| Substance | Color | |
|---|---|---|
| Wine dark to Black[5] | ||
| Moderate olive | ||
| Brilliant yellow green | ||
| Dark olive | ||
| Deep orange yellow | ||
| Dark olive | ||
| Moderate bluish green | ||
| Dark yellowish green | ||
| Diacetylmorphine (Heroin) | Moderate reddish brown | |
| Dark olive brown | ||
| Very reddish brown | ||
| Greyish olive | ||
| Dark olive | ||
| Deep reddish orange | ||
| Moderate olive green | ||
| Bluish black | ||
| Bluish black[6] | ||
| Dark yellowish brown | ||
| Dark greyish blue | ||
| Very orange yellow | ||
| Brilliant orange yellow | ||
| Dark greyish reddish brown | ||
| Olive black | ||
| Dark greenish yellow | ||
| Deep orange | ||
| Dark reddish brown | ||
| Green [7] | ||
| Paramethoxyamphetamine (PMA) | Reddish brown | |
| Paramethoxymethamphetamine (PMMA) | Reddish brown | |
| Salt (NaCl-HCl) | Strong orange |