1. Chapter 7
Drugs
Kendall/Hunt

2. Chapter 7
Drugs and Crime
A drug is a natural or synthetic substance designed to affect the subject psychologically or physiologically.
“Controlled substances” are drugs that are restricted by law.
The Controlled Substances Act is a law that was enacted in 1970; it lists illegal drugs, their categories, and penalties for possession, sale, or use.
Kendall/Hunt

3. Controlled Substances Act
Chapter 7
Controlled Substances Act
Schedule I—high potential for abuse; no currently accepted medical use in the U.S.
Examples: heroin (diacetylmorphine), LSD, marijuana, ecstasy (MDMA)
Schedule II—high potential for abuse; currently accepted medical use with severe restrictions;
Examples: cocaine, morphine, amphetamines (including methamphetamines), PCP, Ritalin
Schedule III—lower potential for abuse than the drugs in I or II; currently accepted medical use
Examples: intermediate-acting barbiturates, anabolic steroids, ketamine, codeine
Schedule IV—low potential for abuse relative to drugs in III; currently accepted medical use
Examples: stimulants and depressants including Valium, Xanax, Librium, phenobarbital
Schedule V—low potential for abuse; currently accepted medical use in the U.S.;
Examples: over-the-counter medications
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4. Stimulants: elevate a person’s mood temporarily, relieve some symptoms of depression, usually not physically addictive but can cause psychological dependence. Examples: cocaine, and methamphetamine.
Depressants: relieve anxiety, nervousness and restlessness; highly addictives; sudden withdrawal can be fatal. Examples: barbiturates, alcohol, diazepam (valium), quaaludes.
Hallucinogens: cause auditory and visual hallucinations. Examples: marijuana, LSD, PCP, mescaline (peyote), psilocybin (mushrooms)
Narcotics: sleep-inducing, central nervous system depressants; derived from the opium poppy. Examples: opium, morphine, heroin, methadone, codeine, oxycodone

5. Human Components Used for Drug Analysis
Chapter 7
Human Components Used for Drug Analysis
Blood
Urine
Hair
Gastric contents
Bile
Liver tissue
Brain tissue
Kidney tissue
Spleen tissue
Vitreous humor of the eye
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6. Physicians’ Desk Reference
Chapter 7
Physicians’ Desk Reference
PDR—A Physicians’ Desk Reference is used to identify manufactured pills, tablets, and capsules. It is updated each year. This can sometimes be a quick and easy identifier of the legally made drugs that may be found at a scene. The reference book gives a picture of the drug and states whether it is prescription, over-the-counter, or a controlled substance; it gives more detailed information about the drug as well.
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7. Screening Tests: add one or more chemical reagents to a suspected drug and observe a color change. Ex: marijuana turns purple, cocaine turns turquoise. Screening tests are not used to confirm the presence of a specific drug because there could be many drugs that give similar positive reactions.
Separation Tests: Most illicit drugs are diluted with other substances. Gas chromatography can separate the pure drug from the cutting agents (sugars, powders, etc.)
Confirmation Tests: Mass spectrometry confirms specific drugs

8. Drug Identification, continued
Chapter 7
Drug Identification, continued
Screening or presumptive tests only tell that the drug is possibly present.
Confirmatory tests tell that the drug is positively present.
(Screening tests are easier, cheaper, and quicker to use.)
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9. Chapter 7
Chromatography
A technique for separating mixtures into their components
Includes two phases—a mobile one that flows past a stationary one
The mixture interacts with the stationary phase and separates
Types:
Paper
Thin-layer (TLC)
Gas (GC)
Pyrolysis gas (PGC)
Liquid (LC)
High-performance liquid (HPLC)
Column
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10. Paper Chromatography Stationary phase—paper
Chapter 7
Paper Chromatography
Stationary phase—paper
Mobile phase—a liquid solvent
Capillary action moves the mobile phase through the stationary phase.
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11. Thin-layer Chromatography
Chapter 7
Thin-layer Chromatography
Stationary phase—a thin layer of coating (usually alumina or silica) on a sheet of plastic or glass
Mobile phase—a liquid solvent
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12. Chapter 7
Retention Factor (Rf)
This is a number that represents how far a compound travels in a particular solvent.
It is determined by measuring the distance the compound traveled and dividing it by the distance the solvent traveled.
If the Rf value for an unknown compound is close to or the same as that for the known compound, the two compounds are likely similar or identical (a match).
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13. Gas Chromatography Phases Stationary—a solid or a
Chapter 7
Gas Chromatography
Phases
Stationary—a solid or a
viscous liquid that lines a tube
or column
Mobile—an inert gas like nitrogen or helium
Analysis
Shows a peak that is proportional to the quantity of the substance present
Uses retention time instead of Rf for the qualitative analysis
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14. Confirmatory Tests: Spectroscopy
Chapter 7
Confirmatory Tests: Spectroscopy
Spectroscopy—the interaction of electromagnetic radiation with matter
Spectrophotometer—an instrument used to measure and record the absorption spectrum of a chemical substance
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15. Infrared Spectrometry
Chapter 7
Infrared Spectrometry
Material absorbs energy in the near-IR region of the electromagnetic spectrum
Compares the IR light beam before and after it passes through a transparent sample
Result—an absorption or transmittance spectrum
Gives a unique view of the substance; like a fingerprint
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16. Chapter 7
Mass Spectrometry
Gas chromatography has one major drawback: It does not give a specific identification. Mass spectrometry cannot separate mixtures. By combining the two (GC-MS), constituents of mixtures can be specifically identified.
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17. Mass Spectra Each molecular species has its own unique mass spectrum.
Chapter 7
Mass Spectra
Each molecular species has its own unique mass spectrum.
Kendall/Hunt