PART 3Forensic Drug Analysis

CONFIRMATION TESTS

LABORATORY BASED DRUG TESTS

Confirmation TestsTests that are performed after screening tests are complete to signify exactly what the unknown substance is.

Qualitative and Quantitative Tests are performed.

A Qualitative test is performed first (to tell what type of drug is present)

A Quantitative test is done second (to tell how much drug is present.) Example: A white powder maybe 20% cocaine, 80% baking soda

FIVE tests used by Forensic Chemists to determine an

unknown drug

1. COLOR TEST (5) PRESUMPTIVE TEST

2. MICORCRYSTALLINE TEST CONFIRMATION TEST

3. CHROMATOGRAPY TEST (2) CONFIRMATION TEST

4. SPECTROPHOTOMETRY (2) CONFIRMATION TEST

5. MASS SPECTROMETRY CONFIRMATION TEST

COLOR TEST (5)1. Marquis Test= Identifies alkaloid drugs (pH 8.2-11.0). A mixture of

formaldehyde and sulfuric acid drips into the drug for a color change. The color indicates the drug. MOST ECSTACY DRUG KITS have the contents of the Marquis Test. Dark purple= Ecstacy, Orange-brown= Meth, Excederin= dark red

2. Dillie-Koppanyi Test= reagent= methanol Barbiturates turn violet-blue

3. Duquenois-Levine Test= in the test is Ethanal, Vanillin, HCl,

chloroform. Marijuana turns purple

4. Van Urk Test=an aldehyde in HCl/ H2SO4 LSD= purple, Psilocybin (mushrooms)= red-brown

5. Scott Test= reagent= Cobalt thiocyanate/HCl/Chloroform Cocaine turns blue, pink, blue

Spot tests IdentificationReagent Positive Result Possible Drugs Present

Marquis Purple Orange-Brown

Heroin, Morphine, & most opium derivatives

Mixture of Amphetamines and Methamphetamines

Dillie-Koppanyi Violet-Blue Barbiturates

Duquenois-Levine Purple Marijuana

Van Urk Blue-Purple LSD

Scott Test Blue Cocaine

Marquis Dillie-Koppanyi Duquenois-Levine

MICROCYSTALLINE TEST

MICROCYSTALLINE TESTA test in which the scientist adds a drop of the suspected substance to a chemical on a slide. The mixture will begin to form crystals. Each type of drug has an individual crystal pattern when seen under a polarized light microscope.

COCAINE METHAMPHETAMINE

CHROMATOGRAPHY

Forensic Chromatography Lab

LC or GCHigh performance liquid chromatography and gas chromatography are extremely sensitive techniques utilized in the analysis of drugs, body fluids, fire accelerants.

Types of Chromatography

• Paper Chromatography

• Gas Chromatography

• Liquid Chromatography

• Thin-Layer Chromatography

• Ion Exchange Chromatography

• Affinity Chromatography Chromatography is used extensively in forensics, from

analyzing body fluids for the presence of illicit drugs, to fiber analysis, blood analysis from a crime scene, and at airports to detect residue from explosives

CHROMATOGRAPY1. Separate and Identify components

of a drug.

2. It involves passing a mixture dissolved in a "mobile phase" through a stationary phase, which separates the compound to be measured from other molecules in the mixture based on differential partitioning between the mobile and stationary bases

Chromatograph of THC

Thin-Layer Chromatography

• Thin layer chromatography (TLC) is a chromatography technique used to separate mixtures.

• Thin layer chromatography is performed on a sheet of glass, plastic, or aluminum foil, which is coated with a thin layer of adsorbent material, usually silica gel.

• This layer of adsorbent is known as the stationary phase

Gas Chromatography

• Book on chromatography

• $100

• 300 pages of graphs

GC machine• GC machines can cost $600- $30,000

• Average cost is $16,000

GC analysis

Spectrophotometry

Mass Spectrometry

• A band of charged particles of different masses formed when a beam of ions is passed through the deflecting fields of a mass spectroscope, from which the masses of atoms, molecules, or isotopes can be determined.

Mass Spectrum of Ephedrine and Pseudoephedrine

UV-visible light spectrometers

UV-visible light spectrometers are employed for accurate quantitative analysis of colored samples

Infrared (IR) Spectrophotometry

• Equivalent to a human’s fingerprint in terms of drug identification

IR spectrum of Cocaine base

How much does a Mass-Spec cost?

$100,000 to $800,000 depending on functions

Mass Spec of Caffeine

GC/MSGas chromatography/mass

spectrometry• Isolates the drug from any mixing agents or other substances

that might be combined with it. • A small amount of the substance is injected into the gas

chromatograph. • Different molecules move through the chromatograph's column

at different speeds based on their density. • For example, heavier compounds move more slowly, while

lighter compounds move more quickly. • Then the sample is funneled into a mass spectrometer, where

an electron beam hits it and causes it to break apart. • How the substance breaks apart can help the technicians tell

what type of substance it is.

GC/MSGas Chromatograph Mass Spectrometer, is used to separate, detect, identify and determine the content of chemicals in a large variety of samples.

GC/MS is the preferred confirmatory method of analysis by the National Institute on Drug Abuse