Marquis (210 ml): Add 10 ml of 40% formaldehyde solution to 200 ml of concentrated sulfuric acid.

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1 Introduction Spot tests are color tests used for rapid screening of samples to determine what drugs may or may not be present. The principal behind spot tests is based on the fact that classes of compounds generally react in the same fashion producing a similar color. Thus, after employing a series of spot tests, the chemist can limit the possibilities of what an unknown sample may or may not be. The chemist must also keep in mind that these tests are only presumptive and not specific for any individual drug and that there are numerous false positives for each reagent used. Safety Personal protective equipment (PPE) including safety glasses/safety shield, gloves, and lab coat/scrubs must be worn when working with the potentially hazardous materials in this procedure. A fume hood must always be used when working with hazardous gases, solvents, dust, etc. Additional protective equipment may be used at the discretion of the analyst. Appropriate personal protective equipment is specified in the Safety Section of the Quality Assurance Manual (QAM). Disposal of all chemical and biohazardous waste must be performed in accordance with the procedures detailed in the Safety Section of the QAM. Preparation of Spot Test Reagents Marquis (210 ml): Add 10 ml of 40% formaldehyde solution to 200 ml of concentrated sulfuric acid. Acidified Cobalt Thiocyanate (Scott's) (500 ml): Reagent #1: Add 10 grams of cobalt thiocyanate to 500 ml of deionized (DI) water (2% solution). Reagent #2: Add 50 ml concentrated hydrochloric acid (HCl) to 450 ml DI water (10% HCl solution). Add 175 ml of reagent #1 to 325 ml of Reagent #2 for a total volume of 500 ml. Mecke (100 ml): Add 1.0 gram of selenious acid to 100 ml concentrated sulfuric acid. Dille-Kopanyi (100 ml): Reagent #1: Dissolve 0.1 gram of cobalt acetate in 100 ml of methanol plus 0.2 ml of glacial acetic acid. Reagent #2: Dissolve 5.0 ml of isopropylamine in 95 ml of methanol. VERSION: 1 Page 1 of 5

2 Van Urks (PDAB) (10 ml): Dissolve 0.2 grams of para-dimethylaminobenzaldehyde in 5 ml of 95% ethanol and add 5 ml of concentrated HCl. Ferric Chloride (100 ml): Dissolve 5.0 grams of ferric chloride into 100 ml of DI water (5% solution). Tannic Acid Solution (volume as required): A saturated solution of tannic acid in DI water. Sodium Nitroprusside (Simon's) (50 ml): Reagent #1: Dissolve 0.5 grams of sodium nitroferricyanide in 50 ml of DI water. Reagent #2: Take 9 ml of reagent #1 and add 1 ml of acetaldehyde. Reagent #3: Dissolve 1.0 gram of sodium carbonate in 50 ml of DI water. Sanchez Solution (10 ml): Add 0.5 ml of acetic acid to a saturated aqueous solution of furfural. Janovsky Reagent (100 ml): Reagent #1: Dissolve 2.0 grams of m-dinitrobenzene in 100 ml of methanol. Reagent #2: Dissolve grams of potassium hydroxide in 100 ml of DI water for a concentration of 5 N. GHB Color Test (volume as required): Bromocresol Green: Add 7.5 milligrams of bromocresol green to 25 ml of 4:1 methanol:water adjusting the ph to 7.0 with 0.1 N sodium hydroxide (100 mg in 25 ml of water). Methyl Orange: Add 2.5 milligrams of methyl orange to 25 ml of water adjusting the ph to 7.0 with 0.1 N sodium hydroxide. Modified Schweppes Reagent: Reagent # 1: 0.5 grams of dextrose in 5 ml of DI water Reagent # 2: 0.6 grams of aniline hydrochloride in 5 ml of methanol Mix reagent # 1 and reagent # 2 together and dilute to 20 ml with methanol Mix bromocresol green and methyl orange together in a 1:1 ratio and then mix with the modified Schweppes reagent in a 3:1 ratio (final color is bright orange). Liebermann s Reagent (10 ml): Dissolve 1.0 gram of potassium nitrite in 10 ml of concentrated sulfuric acid. VERSION: 1 Page 2 of 5

3 Must be prepared in a water bath. The concentrated sulfuric acid must be added 1 ml at a time to the potassium nitrite. Performing Spot Tests A spot test is usually performed by first adding one or two drops of the reagent into a clean depression well of a spot plate as a control to ensure no colors are observed due to contamination. Then a small amount of sample is added (approximately 1-5 mg) and the color change is observed. The following is a list of the exceptions to the above procedure: Dille-Koppanyi: Add two drops of reagent #1 to a small depression in a spot plate and add 1-5 mg of the sample. Add two drops of reagent #2. Tannic Acid: Place a small amount of sample in a clear, clean test tube and dissolve the sample in approximately 2.5 ml of DI water. Add the same volume of the tannic acid solution to the same test tube. Note the color of any precipitate formed. Sodium Nitroprusside: Add two drops of reagent #2 to a clean depression well of a spot plate and then add a small amount of sample. Add 2 drops of reagent #3. Janovsky Reagent: Add three drops of reagent #1 and three drops of reagent #2 to a clean depression well of a spot plate and then add a small amount of the sample. Spot tests must be performed on all unknown powders and all tablet pieces where the combination of the piece shape, color and partial identifier is not enough to ensure the piece is the same as the whole tablets. Observation of Color Result Marquis Reagent Orange Amphetamine and some similar types of compounds such as methamphetamine, mescaline, phentermine, pethidine group (slow reaction) Purple Heroin, codeine, morphine and other opiates Reddish-purple Methapyrilene, tri-cyclic anti-depressants Black MDA type compounds Yellow Diphenhydramine, STP, MDPV, Methylone Light pink Aspirin (slow reaction) may add a small amount of sodium bicarbonate to speed up color development VERSION: 1 Page 3 of 5

4 Yellow to Black 5-MeO-DIPT HCl (Foxy) Cobalt Thiocyanate (acidified) Blue precipitate* Cocaine, meperidine, α-pvp Blue Quinine, PCP (slight reaction), lidocaine (slight reaction), methadone, methaqualone (in tablet preparations), MDPV UV Lamp Blue fluorescence Quinine/quinidine Bright Blue in MeOH LSD and other ergot alkaloids Mecke Reagent Green Heroin Blue-Green Codeine, morphine Yellow-Green Dilaudid, dicodid Dille-Kopanyi Reagent Purple - Barbiturates, glutethimide, diphenylhydantoin Ferric Chloride Reagent Purple precipitate - Salicylates Tannic Acid Reagent White precipitate - Caffeine Sodium Nitroprusside Blue - Methamphetamine Slow pink to red - Amphetamine or other primary amines Purple - TFMPP, BZP Blue-Purple MDPV, Mephedrone, Methylone Sanchez Reagent Red - Benzocaine, procaine, other primary aromatic amines VERSION: 1 Page 4 of 5

5 Janovsky Reagent Purple - Flunitrazepam GHB Color Test Green - GHB Van Urks (PDAB) Grey-Purple - LSD Blue-Grey - Psilocyn Red-Brown Psilocybin Liebermann s Reagent Yellow, Orange, Brown - Synthetic Cannabinoid Note: The above list is not inclusive *A precipitate is commonly, but not always, observed for these types of samples. References Analysis of Drugs Manual; DEA, U.S. Department of Justice, Office of Forensic Sciences, 2nd ed. Clarke's Isolation and Identification of Drugs; Moffat, A. C. et al., The Pharmaceutical Press: London, 1986, 2nd ed. SWGDRUG Recommendations 4th Ed., , Basic Training program for Forensic Drug Chemists; DEA, U.S. Department of Justice, Office of Forensic Sciences, 3rd ed. VERSION: 1 Page 5 of 5