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Drugs & 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.
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Drugs & 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.
Controlled Substance Act • Schedule I • high potential for abuse • no currently accepted medical use in the U.S. • lack of accepted safety for use under medical supervision • Examples: heroin (diacetylmorphine) LSD, marijuana, ecstasy (MDMA)
Schedule II • high potential for abuse • a currently accepted medical use with severe restrictions • Abuse may lead to severe psychological or physical dependence • Examples: cocaine, morphine, amphetamines (including methamphetamines), PCP, Ritalin
Schedule III • lower potential for abuse than the drugs in I or II • a currently accepted medical use in the U.S. • abuse may lead to moderate physical dependence or high psychological dependence • Examples: intermediate-acting barbiturates, anabolic steroids, ketamine
Schedule IV • low potential for abuse relative to drugs in III • a currently accepted medical use in the U.S. • abuse may lead to limited physical or psychological dependence relative to drugs in III • Examples: stimulants and depressants including Valium, Xanax, Librium, phenobarbital, Darvon
Schedule V • low potential for abuse relative to drugs in IV • currently accepted medical use in the U.S. • abuse may lead to limited physical or psychological dependence relative to drugs in IV • Examples: codeine found in low doses in cough medicines
Illegal or Illicit? • An illegal drug is a drug that is against the law to have, use, or distribute. • An illicit drug is a legal drug used in an inappropriate or illegal way.
Summary Questions: Read p, • What are the 5 categories of controlled substances? • What are the differences among a controlled substance, an illicit drug, a prescriptive drug, and an OTC drug? • How are illicit drugs classified? • How do hallucinogens affect the body? • What is the most widespread hallucinogen? • How does marijuana affect the body? • From what is marijuana derived from? • From what is LSD derived from? • How does LSD affect the body? • What is blotter acid? • How does PCP affect the user? • What was PCP originally manufactured and sold as? • How does “Special K” affect the user? What is Ketamine used for? • How do stimulants affect the body? • How many pounds of cocoa plants produce 1 lb of cocaine? • What habit-forming non-controlled stimulant is often found in cigarettes? • What is Qat? How is it used? • Which stimulant is found in “Mountain Dew”? • How do narcotics affect the user? • Name 6 OTC analgesics found at your local CVS. • Which prescription narcotic is most often abused? • What is the PDR? How is it used?
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
Physicians Desk Reference PDR—A Physicians’ Desk Reference • used to identify manufactured pills, tablets, and capsules. • updated each year. • quick and easy identifier of the legally made drugs that may be found at a scene. • gives a picture of the drug • states whether it is prescription, over-the-counter, or a controlled substance • detailed information about the drug
Drug Identification Screening or presumptive tests • Only tell that the drug is possibly present • Easier, cheaper, & quicker to use • Spot or color tests • Microcrystalline test - a reagent is added, producing a crystalline precipitate that is unique for a certain drug • Chromatography Confirmatory tests • Tell that the drug is positively present • Spectrophotometry • Ultraviolet (UV) • Visible • Infrared (IR) 3) Mass spectrometry
Presumptive Color Tests • Marquis—turns purple in the presence of most opium derivatives and orange-brown with amphetamines • Dille-Koppanyi—turns violet-blue in the presence of barbiturates • Duquenois-Levine—turns a purple color in the presence of marijuana • Van Urk—turns a blue-purple in the presence of LSD • Scott test—color test for cocaine; blue
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 of Chromatography • Paper • Thin-layer (TLC) • Gas (GC) • Pyrolysis gas (PGC) • Liquid (LC) • High-performance liquid (HPLC) • Column
Paper Chromatography • Stationary phase—paper • Mobile phase—a liquid solvent • Capillary action moves the mobile phase through the stationary phase.
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
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).
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 Rffor the qualitative analysis
Uses of Gas Chromatography • Not considered a confirmation of a controlled substance • Used as a separation tool for mass spectroscopy (MS) and infrared spectroscopy (IR) • Used to quantitatively measure the concentration of a sample. (In a courtroom, there is no real requirement to know the concentration of a substance. It does not affect guilt or innocence.)
Summary Questions: Read p. • What is a spot test? • What does a positive spot test indicate? Negative? • What is chromatography? • What are the types of chromatography? • What are the legal aspects of violent behavior associated with the ingestion of prescription drugs? • How can you test a person’s plasma to determine if they took aspirin? • What is metabolism? • How much Salicylate concentration would remain in a person’s plasma after 3 hours? • What is the presumptive test for marijuana? • What does a positive Duquenois-Levin test indicate? • What spot tests are used for the following: LSD? Amphetamines, cocaine, heroine, barbiturates? • What is EMIT? • As sample of light brown powder found in the kitchen of an alleged drug house gives a blue precipitate with cobalt thiocyanate. What is it? Is there enough evidence to prosecute? • In the “incense” incident described on p. 189, about two pounds of the material was retrieved from the car. What would be the maximum sentence if the driver were convicted as a first offense? (See Appendix B) • If, in the incident at the Detroit airport, the film canister contained 50 grams of cocaine and 10 more grams were found in the man’s camera bag, what could be the sentence if he were convicted as a first offense? (See Appendix C)
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
Spectrophotometry • Components • A radiation source • A frequency selector • A sample holder • A detector to convert electromagnetic radiation into an electrical signal • A recorder to produce a record of the signal • Types • Ultraviolet • Visible • Infrared
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
Mass Spectrometry • Does not give a specific identification & cannot separate mixtures. • In a mass spectrometer, an electron beam is directed at sample molecules in a vacuum chamber. The electrons break apart the sample molecules into many positive-charged fragments. These are sorted and collected according to their mass-to-charge ratio by an oscillating electric or magnetic field. • By combining the two (GC-MS), constituents of mixtures can be specifically identified.
Mass Spectra • Each moleculalr species has its own unique mass spectrum.
Spectrophotometry & Mass Spectrometry • Both work well in identifying pure substances. • Mixtures are difficult to identify in both techniques. • Both are compared to a catalog of knowns.
People of Historical Significance • Arthur Jeffrey Dempster (1918), developed the first modern mass spectrometer (100x more accurate). • Francis William Aston (1922) invention of the mass spectrograph. This enabled him to identify no fewer than 212 of the 287 naturally occurring elemental isotopes.
Summary Questions: Read p. • What are 2 analytical techniques most confirmatory test are based upon? • How is the IR Spectrum of each substance like a fingerprint? • What is the basic instrument now in use for taking IR Spectra? How much does it cost? • Draw a simple schematic of an infrared spectrophotometer? • How does a mass spectrometer work? • Why is mass spectrometry difficult to use with mixtures? • What are some substances that illicit drugs are often cut? • How much does a gas chromatograph-mass spectrometer cost? • What is the electromagnetic spectrum (EMS)? • Which end of the EMS is the high energy part? • How is the EMS used in analytical analyses? • What is the difference between absorbance and transmittance in spectroscopy? What is their relationship to analyte concentration? • You have tested a sample of white powder with cobalt thiocyanate reagent and obtained a blue precipitate. You think you have __________________, but you ask the spectroscopy lab for a confirmation. They provide the spectrum below. What is your sample? (Compare with Appendix D) • You get a violet-blue color with Marquis reagent on a sample submitted to your lab. You ask the mass spectroscopy lab to check it for you, and they submit the following mass spectra. What is your sample? (Compare with Appendix E) • Infrared spectra of butanol (butyl alcohol) and butanal (butyraldehyde) are given below. Which do you think is the aldehyde? Why?