The Froehde reagent is used as a simple spot-test to presumptively identify alkaloids, especially opioids, as well as other compounds. It is composed of a mixture of molybdic acid or a molybdate salt dissolved in hot, concentrated sulfuric acid, which is then dripped onto the substance being tested.
The United States Department of Justice method for producing the reagent is the addition of 100 ml of hot, concentrated (95–98%) sulfuric acid to 0.5 g of sodium molybdate or molybdic acid. [1]
The Virginia Department of Forensic Science method uses 0.5 g ammonium molybdate per 100 ml H2SO4 (conc.) [2]
Unheated sulfuric acid can be used to prepare the reagent in a less dangerous manner, but 2–4 hours must be allowed for the molybdate to dissolve.
Substance | Color |
---|---|
Amphetamine | No reaction [3] or Red [4] |
Cathinone | No reaction [5] |
Methcathinone | No reaction [5] |
4-MMC | No reaction [5] |
3-FMC | No reaction [5] |
MDMA | Black [3] |
Methylone | Bright yellow [5] |
MDPV | Bright yellow [5] |
Butylone | Yellow > Green [6] |
3,4-DMMC | Light brown [6] |
Naphyrone | Orange [6] |
PMA | Pale green [3] |
PMMA | Pale green [3] |
4-MeO-PCP | Light yellow [6] |
Methoxetamine | Yellow - Green [6] |
3-HO-PCE | Black [6] |
5-MeO-DALT | Yellow [6] |
4-AcO-DALT | Yellow > Green [6] |
4-HO-MET | Yellow > Green [6] |
4-HO-MIPT | Yellow > Green [6] |
4-AcO-DET | Yellow > Green [6] |
aMT | Yellow [6] |
5-IT | Red brown [6] |
5-APB | Dark purple [6] |
6-APB | Purple [6] |
Camfetamine | Tan > Dark yellow [6] |
Methiopropamine | Light brown [6] |
MDAI | Green > Black [6] |
5-IAI | Orange [6] |
Allylescaline | Green > Black (fast) [6] |
2C-T-2 | Orange > Purple [6] |
2C-B | Yellow [2] |
2C-P | Green [6] |
b-methoxy-2C-D | Red [6] |
Acetaminophen | Pale blue [2] |
Aspirin | Greyish purple [1] or Blue > Purple [2] |
Alimemazine | Purple red [4] |
Chlorphentermine | Green [4] |
Chlorpromazine HCl | Very deep red [1] [4] |
Contac HCl | Moderate olive brown [1] |
Dimethoxy-meth HCl | Very yellow green [1] |
Diphenhydramine | Orange [4] |
Doxepin HCl | Deep reddish brown [1] [4] |
Dristan | Light bluish green [1] |
Ephedrine | Brown [4] |
Exedrine | Brilliant blue [1] |
Flurazepam | Orange [4] |
LSD | Moderate yellow green, [1] Yellow Green [4] |
Mace | Light olive yellow [1] |
MDA HCl | Greenish black [1] [4] |
Mescaline | Green or brown or light yellow [4] |
Meperidine | Grey [2] |
Modafinil | Deep orange/red [7] |
Morphine monohydrate | Deep purplish [2] Red [1] > Slate [2] |
Heroin HCl | Deep purplish red [1] [4] > Green [2] |
Opium | Brownish black [1] [4] |
Oxycodone HCl | Strong yellow [1] [2] - Blue [4] or Green [4] |
Codeine HCl | Very dark [1] Green [4] > Red - Brown [2] |
Hydromorphone | Blue > Purple [2] |
Hydrocodone | Light [2] Yellow [4] |
Pentazocine | Blue [2] [4] |
Pethidine | Yellow [4] |
Phenoxymethylpenicillin | Blue [2] |
Phenyltoloxamine | Green [4] |
Promazine | Orange [4] |
Promethazine | Purple red [4] |
Propoxyphene HCl | Dark greyish red [1] [4] or Brown [2] |
Propylhexadrine | Purple red [4] |
Sugar | Brilliant yellow [1] |
Salicylic acid | Purple red [4] |
Tetracycline | Purple red [4] |
Thioridazine | Purple red [4] |
Guaifenesin | Green with purple streaks [2] |
Methapyrilene | Purple [2] |
Pyrilamine | Purple [2] |
Trifluoperazine | Orange [4] |
Triflupromazine | Orange [4] |
Marquis reagent is used as a simple spot-test to presumptively identify alkaloids as well as other compounds. It is composed of a mixture of formaldehyde and concentrated sulfuric acid, which is dripped onto the substance being tested. The United States Department of Justice method for producing the reagent is the addition of 100 mL of concentrated (95–98%) sulfuric acid to 5 mL of 40% formaldehyde. Different compounds produce different color reactions. Methanol may be added to slow down the reaction process to allow better observation of the colour change.
A drug test is a technical analysis of a biological specimen, for example urine, hair, blood, breath, sweat, or oral fluid/saliva—to determine the presence or absence of specified parent drugs or their metabolites. Major applications of drug testing include detection of the presence of performance enhancing steroids in sport, employers and parole/probation officers screening for drugs prohibited by law and police officers testing for the presence and concentration of alcohol (ethanol) in the blood commonly referred to as BAC. BAC tests are typically administered via a breathalyzer while urinalysis is used for the vast majority of drug testing in sports and the workplace. Numerous other methods with varying degrees of accuracy, sensitivity, and detection periods exist.
Classical qualitative inorganic analysis is a method of analytical chemistry which seeks to find the elemental composition of inorganic compounds. It is mainly focused on detecting ions in an aqueous solution, therefore materials in other forms may need to be brought to this state before using standard methods. The solution is then treated with various reagents to test for reactions characteristic of certain ions, which may cause color change, precipitation and other visible changes.
Reagent testing is one of the processes used to identify substances contained within a pill, usually illicit substances. With the increased prevalence of drugs being available in their pure forms, the terms "drug checking" or "pill testing" may also be used, although these terms usually refer to testing with a wider variety of techniques covered by drug checking.
Ammonium heptamolybdate is the inorganic compound whose chemical formula is (NH4)6Mo7O24, normally encountered as the tetrahydrate. A dihydrate is also known. It is a colorless solid, often referred to as ammonium paramolybdate or simply as ammonium molybdate, although "ammonium molybdate" can also refer to ammonium orthomolybdate, (NH4)2MoO4, and several other compounds. It is one of the more common molybdenum compounds.
Presumptive tests, in medical and forensic science, analyze a sample and establish one of the following:
The Duquenois reagent used in the Rapid Modified Duquenois–Levine test, is an established screening test for the presence of cannabis. The test was initially developed in the 1930s by the French Medical Biochemist, Pierre Duquénois (1904–1986), and was adopted in the 1950s by the United Nations as the preferred test for cannabis, and originally claimed to be specific to cannabis.
Mephedrone, also known as 4-methylmethcathinone, 4-MMC, and 4-methylephedrone, is a synthetic stimulant drug of the amphetamine and cathinone classes. Slang names include drone, M-CAT, White Magic, meow meow and bubble. It is chemically similar to the cathinone compounds found in the khat plant of eastern Africa. It comes in the form of tablets or crystals, which users can swallow, snort or inject, producing effects similar to those of MDMA, amphetamines and cocaine.
Ehrlich's reagent or Ehrlich reagent is a reagent containing p-dimethylaminobenzaldehyde (DMAB) and thus can act as an indicator to presumptively identify indoles and urobilinogen. Several Ehrlich tests use the reagent in a medical test; some are drug tests and others contribute to diagnosis of various diseases or adverse drug reactions. It is named after Nobel Prize winner Paul Ehrlich who used it to distinguish typhoid from simple diarrhoea.
Benzedrone (4-MBC) is a designer drug which has been found since 2010 as an ingredient in a number of "bath salt" mixes sold as recreational drugs.
Pentedrone is a stimulant of the cathinone class that has been sold as a designer drug and has been found since 2010 as an ingredient in a number of "bath salt" mixes sold as legal highs.
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 g of potassium nitrite is used for every 10 mL of sulfuric acid. Potassium nitrite may also be substituted by sodium nitrite. It is used to test for cocaine, morphine, PMA and PMMA.
The Mecke reagent is used as a simple spot-test to presumptively identify alkaloids as well as other compounds. It is composed of a mixture of selenous acid and concentrated sulfuric acid, which is dripped onto the substance being tested.
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 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.
Simon's reagent is used as a simple spot-test to presumptively identify alkaloids as well as other compounds. It reacts with secondary amines like MDMA and methamphetamine to give a blue solution.
The Dille–Koppanyi reagent is used as a simple spot-test to presumptively identify barbiturates. It is composed of a mixture of two solutions. Part A is 0.1 g of cobalt(II) acetate dihydrate dissolved in 100 ml of methanol mixed with 0.2 ml of glacial acetic acid. Part B made up of is 5% isopropylamine (v/v) in methanol. Two drops of A are dropped onto the substance followed by one drop of B and any change in colour is observed.
The Zwikker reagent is used as a simple spot-test to presumptively identify barbiturates. It is composed of a mixture of two solutions. Part A is 0.5 g of copper (II) sulfate in 100 ml of distilled water. Part B consists of 5% pyridine (v/v) in chloroform. One drop of each is added to the substance to be tested and any change in colour is observed.
The Gallic acid reagent is used as a simple spot-test to presumptively identify drug precursor chemicals. It is composed of a mixture of gallic acid and concentrated sulfuric acid.
The Chen-Kao reaction is a chemical method for determining the presence of pseudoephedrine, ephedrine, and similar phenylalkylamines. The reaction is used in spot tests and is also known as Chen-Kao test. The test is often used to distinguish ephedrine, pseudoephedrine, norephedrine, cathinone and methcathinone from amphetamine and methamphetamine, which do not react with Chen’s test reagent.