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Chapter 7 & 8 Drugs and Toxicology. “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. Define. Drug Controlled Substance Illicit Drug
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Chapter 7 & 8Drugs and Toxicology “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
Define • Drug • Controlled Substance • Illicit Drug • Prescription Drug • Over the Counter Drug • Poison Kendall/Hunt Publishing Company
Drug • A natural or synthetic substance designed to affect humans or animals psychologically or physiologically. Kendall/Hunt Publishing Company
Controlled substance • Identified under the Federal Schedules of the Controlled Substances Act Kendall/Hunt Publishing Company
Illicit Drug • An illegal substance used for pleasure but not necessarily defined in the Federal Controlled Substance Act Kendall/Hunt Publishing Company
Prescription Drug • A doctor must prescribe a drug for a specific reason. • Misuse makes it an illicit drug. Kendall/Hunt Publishing Company
Over the Counter (OTC) • No restrictions on purchase • Misuse of these can and does occur • Pseudoephedrine misuse leads to curtailed access Kendall/Hunt Publishing Company
Poison • Almost anything can be a poison if used inappropriately • Poison Control Center frequent calls • Children’s Tylenol • Children’s Vitamins with iron Kendall/Hunt Publishing Company
Chapter 7 & 8Drugs and Toxicology “All substances are poisons. There is none which is not. The right dose differentiates a poison and remedy.” —Paracelsus (1495-1541). Swiss physician and chemist
Drugs Students will learn: • How to apply deductive reasoning to a series of analytical data. • The limitations of presumptive (screening) tests. • The relationship between the electromagnetic spectrum and spectroscopic analysis. • The dangers of using prescription drugs, controlled substances, over-the-counter medications, and illegal drugs. Kendall/Hunt Publishing Company
Drugs Students will be able to: • 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. Kendall/Hunt Publishing Company
Drugs • Describe IR, UV-VIS spectroscopy, and GC-MS • Present and interpret data with graphs. • Use the Physicians’ Desk Reference (PDR) to identify pills. • Use technology and mathematics to improve investigations and communications. Kendall/Hunt Publishing Company
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. Kendall/Hunt Publishing Company
Controlled Substances Act • Schedule I—high potential for abuse; no currently acceptable medical use in the US; a lack of accepted safety for use under medical supervision • Schedule II—high potential for abuse; a currently accepted medical use with severe restrictions; abuse may lead to severe psychological or physical dependence • 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 • 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 • 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 Kendall/Hunt Publishing Company
Examples of Controlled Substances and Their Schedule Placement • Schedule I—heroin (diacetylmorphine), LSD, marijuana, ecstasy (MDMA) • Schedule II—cocaine, morphine, amphetamines (including methamphetamines), PCP, Ritalin • Schedule III—intermediate acting barbiturates, anabolic steroids, ketamine • Schedule IV—other stimulants and depressants including Valium, Xanan, Librium, phenobarbital, Darvon • Schedule V—codeine found in low doses in cough medicines Kendall/Hunt Publishing Company
Identification of Drugs • PDR—Physicians’ Desk Reference • Field Tests—presumptive tests • Laboratory Tests—conclusive tests Kendall/Hunt Publishing Company
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, whether it is a prescription, over the counter, or a controlled substance; as well as more detailed information about the drug. Kendall/Hunt Publishing Company
Product Inserts: use the guide to help you interpret your example. Answer these questions on notebook paper. • 1. Scan your product insert • A. List the generic name and indications • B. List contraindications (and describe what that means) • C. List warnings and adverse reactions • D. Describe dosage • 2. Describe “black box warnings” and give 7 examples…check the handout for these. • Does your product have a black box warning?
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 Drug Identification Kendall/Hunt Publishing Company
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 Presumptive Color Tests Kendall/Hunt Publishing Company
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 Company
Types of Chromatography • Paper • Thin Layer (TLC) • Gas (GC) • Pyrolysis Gas (PGC) • Liquid (LC) • High Pressure Liquid (HPLC) • Column Kendall/Hunt Publishing Company
Paper Chromatography • Stationary phase—paper • Mobile phase—a liquid solvent Capillary action moves the mobile phase through the stationary phase Kendall/Hunt Publishing Company
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 Company
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). Kendall/Hunt Publishing Company
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 Gas Chromatography Kendall/Hunt Publishing Company
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 Company
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 Company
Mass Spectrometer • A machine used to weigh molecules • A molecular scale Kendall/Hunt Publishing Company
How is MS used? • A mass spectrometer helps scientists • ID molecules • Determine how many molecules are present • Determine what atoms are in a molecule • Determine how the atoms are arranged Kendall/Hunt Publishing Company
Pocket change sorted Kendall/Hunt Publishing Company
Sorting and Counting POCKET CHANGE MIXTURE OF MOLECULE AND FRAGMENTS Mixture of different molecule fragments Sort fragments by mass Show amount of each fragment on bar graph • Penny, nickel, dime, quarter, half dollar, dollar • Sort change by value or size • Stack them up to sort them visually Kendall/Hunt Publishing Company
Molecular fragments sorted Kendall/Hunt Publishing Company
HOW? Using ions • An ion is an electrically charged atom or molecule • Molecules must be charged to be measured by a mass spec • A mass spec “weighs” molecules by electrically attracting and repelling ions with carefully controlled charges and force fields. Kendall/Hunt Publishing Company
Let’s get charged up! • First, the mass spec ionizes (or charges) the molecules • It also breaks apart the big molecule into pieces…like tearing apart a jigsaw puzzle • This is called ionization Kendall/Hunt Publishing Company
Sort it out! • It sorts all of these charged particles out by size Kendall/Hunt Publishing Company
Like a pinball machine…a certain amount of force sends the ball where you want it • A different size ball requires different force Kendall/Hunt Publishing Company
What do the patterns tell us?MOLECULAR FINGERPRINTS Scientists recognize the pieces and assemble them to identify the compound. MS Fragments...pieces of a puzzle Each compound produces a unique spectrum.
Mass Spectra Each molecular species has its own unique mass spectrum. Kendall/Hunt Publishing Company
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 Company
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 Company
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 Company
IR Spectrophotometry andMass 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 Company
Blood Urine Hair Gastric Contents Bile Liver tissue Brain tissue Kidney tissue Spleen tissue Vitreous Humor of the Eye Human ComponentsUsed for Drug Analysis Kendall/Hunt Publishing Company
Challenges of Tox • Drugs must be isolated from body components, such as urine, blood, brain vitreous humor, stomach contents, liver, bile, brain Kendall/Hunt Publishing Company
Challenges of Tox • Drugs in the body are changed chemically as the body metabolizes the drug. Scientists must understand the process and look for the metabolites. Kendall/Hunt Publishing Company
Challenges of Tox • If the patient is alive, testing must be fast to provide medical care. • The quantity of drug present is often important. Remember, the difference between medicine and poison is often the dose. Kendall/Hunt Publishing Company