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Chapter 7 Chapter 7 Drugs “Having sniffed the dead man’s lips, I detected a slightly sour smell, and I came to the conclusion that he had poison forced.

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Presentation on theme: "Chapter 7 Chapter 7 Drugs “Having sniffed the dead man’s lips, I detected a slightly sour smell, and I came to the conclusion that he had poison forced."— Presentation transcript:

1 Chapter 7 Chapter 7 Drugs “Having sniffed the dead man’s lips, I detected a slightly sour smell, and I came to the conclusion that he had poison forced upon him.” — Sherlock Holmes, in Sir Arthur Conan Doyle’s A Study in Scarlet

2 Chapter 7 CSI and Drugs something ironic…CSI and Drugs

3 Chapter 7 Drugs  Apply deductive reasoning to a series of analytical data.  Learn the limitations of presumptive (screening) tests.  The dangers of using prescription drugs, controlled substances, over-the- counter medications, and illegal drugs. 2 You will:

4 Chapter 7 Drugs  Identify chemically identify illicit drug types.  Classify the types of illicit drugs and their negative effects.  Discuss the federal penalties for possession and use of controlled substances.  Explain the need for confirmatory tests….. 3 You will:

5 Chapter 7 In the United States, as much as 75 percent of the evidence being examined in forensic laboratories is considered drug related, either the drugs themselves or evidence from drug-related crimes. 4

6 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  Controlled Substances Act is a law that was enacted in 1970; it lists illegal drugs, their category and their penalty for possession, sale or use. 5

7 Chapter 7 Hallucinogens are mostly naturally occurring substances that can change normal thought processes, perceptions, and moods marijuana, LSD, PCP… 6

8 Chapter 7 Stimulants act on the central nervous system to make the user feel better and increase his or her energy alertness while suppressing appetite and fatigue caffeine, cocaine Kendall/Hunt Publishing Company7

9 Chapter 7

10 Narcotics analgesics: substances affecting the central nervous system to relieve pain. Mild analgesics are found in many over-the-counter (OTC) drugs such as aspirin, Tylenol, and Motrin. Narcotics are the opiates: heroin, morphine, codeine 9

11 Chapter 7 Depressants Slow central nervous system: Ethyl alcohol is a common depressant—, barbiturates, Quaaludes 10

12 Chapter 7 Controlled Substances  Schedule I—high potential for abuse; no currently acceptable medical use in the US; a lack of accepted safety for use under medical supervision 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 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 US; abuse may lead to moderate physical dependence or high psychological dependence intermediate acting barbiturates, anabolic steroids, ketamine

13 Chapter 7  Schedule IV—low potential for abuse relative to drugs in III; a currently accepted medical use in the US; abuse may lead to limited physical or psychological dependence relative to drugs in III other 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 US; abuse may lead to limited physical or psychological dependence relative to drugs in IV codeine found in low doses in cough medicines, and painkillers such as percocet, vicoden

14 Chapter 7 Amphetamines - Includes: diet agents decongestants medication for parkinsons Cocaine Quinine can cross react with the following immunoassays : cocaine EIA but not cocaine FPIA Any drug with cain, or caine will show up. lidocaine, Novocain, Tylenol 3 with codeine, etc. They are all made from the same opiate family. If you have to take a test, just have a prescription available to prove its a prescription, not a drug habit. Many people have had false positives that have ruined their career or family. This is due to the fact that people metabolize drugs at different speeds. It is also caused by enzymes that break down the drugs. One person can have a different enzyme break down a drug resulting in a different metabolite showing up on a screen. Drug tests are never 100% accurate. Novocain may show up for amphetamine, cocaine, even opiates. I'm sure of this because I am a lab worker at a major testing corp.

15 Chapter 7 Marijuana Sustiva can cross react with THC EIA Immunoassays can’t distinguish between smoked marijuana and Marinol Opiates can cross react with antibiotics, levofloxacin and ofloxacin can yield false positive results for: imipramine papaverine rifampin

16 Chapter 7 Benzodiazepines can cross react with oxaprozin (daypro) can cross react with diphenhydramine can cross react with sertaline (zoloft) False/positive results Barbituates primidone (mysoline) metabolized in the liver to phenylethylmalonamide and phenobasrbital which are excreted in the urine phenytoin can cross react

17 Chapter 7 Identification of Drugs  PDR—Physicians’ Desk Reference  Field Tests—presumptive tests  Laboratory Tests—conclusive tests Kendall/Hunt Publishing Company16

18 Chapter 7 PDR The Physicians' Desk Reference (PDR) is a published compilation of manufacturers' prescribing information on prescription drugs, updated annually. While designed to provide physicians with the full legally mandated information relevant to writing prescriptions (just as its name suggests), it is widely available in libraries and bookstores, widely used by other medical specialists, and in significant part valuable to consumers.

19 Chapter 7 it is used to identify manufactured pills, tablets and capsules. 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, whether it is a prescription, over the counter, or a controlled substance; as well as more detailed information about the drug. Kendall/Hunt Publishing Company18

20 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 Kendall/Hunt Publishing Com19

21 Chapter 7 The vitreous humor or body is the clear gel that fills the space between the lens and the retina of the eyeball.

22 Chapter 7 Urine Testing General Precautions: should be taken to ensure that a urine sample cannot be altered or diluted during the collection or procedure and that the information on the urine bottle and the documentation can identify the individual from whom the sample was collected.

23 Chapter 7 Drug Identification Screening or presumptive tests  Spot or color tests  Microcrystalline test— a reagent is added that produces a crystalline precipitate which is unique for a certain drug.  Chromatography Confirmatory tests  Spectrophotometry  Ultraviolet (UV)  Visible  Infrared (IR)  Mass spectrometry Kendall/Hunt Publishing Company22

24 Chapter 7 Presumptive Color Tests  Marquis—turns purple in the presence of most opium derivatives and orange-brown with amphetamines  Dillie-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 Kendall/Hunt Publishing Company23

25 Chapter 7 SALIVA (ORAL FLUID) DRUG TESTING USED FOR MANY YEARSCAN USE IMMUNOASSAY, GAS CHROMATOGRAPHY OR GC/MS

26 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. Kendall/Hunt Publishing Company25

27 Chapter 7 Types of Chromatography  Paper  Thin Layer (TLC)  Gas (GC)  Pyrolysis Gas (PGC)  Liquid (LC)  High Pressure Liquid (HPLC)  Column Kendall/Hunt Publishing Company26

28 Chapter 7 Paper Chromatography  Stationary phase— paper  Mobile phase—a liquid solvent Kendall/Hunt Publishing Company27 Capillary action moves the mobile phase through the stationary phase

29 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 Kendall/Hunt Publishing Company28

30 Chapter 7 Retention Factor (R f ) how far a compound travels  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 R f 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). Kendall/Hunt Publishing Company29

31 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 R f for the qualitative analysis Kendall/Hunt Publishing Company30

32 Chapter 7 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). Kendall/Hunt Publishing Company31

33 Chapter 7 Spectroscopy  Spectroscopy—the interaction of electromagnetic radiation with matter.  Spectrophotometer—an instrument used to measure and record the absorption spectrum of a chemical substance. Kendall/Hunt Publishing Company32

34 Chapter 7 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 Kendall/Hunt Publishing Company33

35 Chapter 7 Infrared Spectometry  Material absorbs energy in the near-IR region of the electromagnetic spectrum.  Compares the IR light beam before and after passing through a transparent sample.  Result—an absorption or transmittance spectrum  Gives a unique view of the substance; like a fingerprint Kendall/Hunt Publishing Company34

36 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 (GCMS), constituents of mixtures can be specifically identified. Kendall/Hunt Publishing Company35

37 Chapter 7 Mass Spectrometry 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 a magnetic field. Kendall/Hunt Publishing Company36

38 Chapter 7 Mass Spectra Each molecular species has its own unique mass spectrum. Kendall/Hunt Publishing Company37

39 Chapter 7 IR Spectrophotometry and 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 Kendall/Hunt Publishing Company38

40 Chapter 7 People of Historical Significance Arthur Jeffrey Dempster was born in Canada, but studied and received his PhD from the University of Chicago. He began teaching physics there in 1916. In 1918, Dempster developed the first modern mass spectrometer. His version was over 100 times more accurate than previous ones developed, and established the basic theory and design of mass spectrometers that is still used to this day. Kendall/Hunt Publishing Company39

41 Chapter 7 People of Historical Significance Francis William Aston was a British physicist who won the 1922 Nobel Prize in Chemistry for his work in the invention of the mass spectrograph. He used a method of electromagnetic focusing to separate substances. This enabled him to identify no fewer than 212 of the 287 naturally occurring elemental isotopes. Kendall/Hunt Publishing Company40

42 Chapter 7 Drug Sniffing Wasps


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