The Liebermann reagent named after Hungarian chemist Leo Liebermann (1852-1926) is used as a simple spot-test to presumptively identify alkaloids as well as other compounds. It is composed of a mixture of potassium nitrite and concentrated sulfuric acid.[1][2] 1 g of potassium nitrite is used for every 10 mL of sulfuric acid.[3] Potassium nitrite may also be substituted by sodium nitrite.[4][5] It is used to test for cocaine, morphine, PMA and PMMA. The test is performed by scraping off a small amount of the substance and adding a drop of the reagent (which is initially clear and colorless). The results are analyzed by viewing the color of the resulting mixture, and by the time taken for the change in color to become apparent.
Substance | Color |
---|---|
Alprazolam | No reaction |
Cocaine | Yellowish[2] |
Morphine | Black[2][6] |
Atropine | Red - orange[citation needed] |
Yohimbine | Blue[citation needed] |
PMA and PMMA | Purple - brown[7] |
MDMA | Intense brown[8] - black[7] |
Amphetamine | Orange to red[9] |
Methamphetamine | Red[6] |
4-FA | Orange[10][11] |
Cathinone | Bright yellow[8] |
Methcathinone | Bright yellow[8] |
4-MMC | Bright yellow[8] |
N,N-DMC | Faint yellow[8] |
3-FMC | No reaction[8] |
4-MOMC | Faint orange[8] |
Methylone | Orange > brown[8] |
MDPV | Yellow > green[8] |
4-Me-PPP | Orange[12] |
Brephedrone | Yellow[12] |
4-MEC | Orange[12] |
Pentedrone | Yellow[12] |
4-Methylbuphedrone | Yellow[12] |
Buphedrone | Yellow[12] |
Butylone | Yellow > brown[12] or green > brown[8] |
3,4-DMMC | Orange[12] |
Naphyrone | Brown[12] |
Benzedrone | Orange[12] |
JWH-307 | Dark yellow[12] |
AB-001 | Dark yellow[12] |
CB-13 | Dark green[12] |
JTE-907 | Black (bubbling)[12] |
UR-144 | Dark red[12] |
URB-597 | Yellow brown[12] |
URB602 | Dark brown[12] |
URB754 | Light brown[12] |
AM-1248 | Dark yellow[12] |
AB-034 | Red-orange > dark red[12] |
A-796,260 | Red-orange > dark red[12] |
A-834,735 | Red-orange > dark red[12] |
FUR-144 | Dark red[12] |
APINACA | No color change[12] |
JWH-073 | Yellow - brown[12] |
JWH-018 | Yellow - brown[12] |
JWH-200 | Dark yellow - brown[12] |
AM-2201 | Yellow - brown[12] |
JWH-203 | Yellow - orange[12] |
RCS-4-C4 homolog | Brown[12] |
AM-694 | Dark yellow[12] |
MAM-2201 | Green - brown[12] |
AM-2233 | Yellow[12] |
STS-135 (drug) | Brown[12] |
4-MeO-PCP | Brown[12] |
Methoxetamine | Orange - brown[12] |
Ethketamine | Pale yellow[12] |
3-HO-PCE | Dark brown[12] |
5-MeO-DALT | Dark brown - black[12] |
4-methyl-aET | Brown[12] |
4-AcO-DALT | Black[12] |
4-HO-MET | Black[12] |
4-HO-MIPT | Black[12] |
4-AcO-DET | Black[12] |
DPT | Dark brown |
aMT | Black[12] |
5-IT | Dark brown[12] |
5-APB | Black[12] |
6-APB | Dark purple[12] |
Camfetamine | Dark red[12] |
Methiopropamine | Dark brown[12] |
MDAI | Green > black[12] |
5-IAI | Dark brown[12] |
Pethidine | Red - orange[13] |
Mescaline | Black[13] |
Allylescaline | Brown - black[12] |
2C-T-2 | Red[12] |
2C-P | Green[12] |
2C-C | Yellow > black > clear |
2C-B | Yellow → black |
b-methoxy-2C-D | Green[12] |
Original source: https://en.wikipedia.org/wiki/Liebermann reagent.
Read more |