Js 112: Forensic Chemistry: Drugs/Tox Assignments



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JS 112: Forensic Chemistry: Drugs/Tox


Assignments

    • Assignments:
      • Read Chapters 8 and 9- Drugs and Toxicology for weds.
      • Read Chapters 10 and 12 Bloodstains and Serology for mon.
      • Extra credit:Due Monday 19 April
        • Find 1 article on alcohol abuse leading to a fatality e.g. DUI from a news story within the last 3 months.
        • Write a 300 word summary and 3 questions and 3 answers on the article. Be prepared to discuss it in class.
      • Bring Lab books with Reports Weds-
      • Study for quiz for Monday 19 April on Drugs, Dr. Orrego Lecture and Blood reading.


What is a Drug?

  • A drug is a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other higher order animals



Drug Dependence

  • Psychological dependence- The conditioned use of a drug caused by underlying emotional needs.

  • Physical dependence- Physiological need for a drug that has been brought about by its regular use. Dependence is characterized by withdrawal sickness when administration of the drug is abruptly stopped.





Potential of commonly abused drugs to produce dependency with regular use

  • Drug Psychological Physical

  • Narcotics

    • Morphine High Yes
    • Heroin High Yes
    • Methadone High Yes
    • Codeine Low Yes
  • Depressants

    • Barbiturates (short-acting)High Yes
    • Barbiturates (long-acting) Low Yes
    • Alcohol High Yes
    • Diazepam (Valium) Moderate Yes
  • Stimulants

    • Amphetamines High ?
    • Cocaine High No
    • Caffeine Low No (?)
    • Nicotine High Yes
  • Hallucinogens

    • Marijuana Low No
    • LSD Low No
    • PCP High No


Factors influencing control

  • Individual, social, cultural, legal, and medical

  • Weigh the beneficial aspects of the drug vs harm the abuse will do to the individual and society

  • Prohibition of alcohol led to disastrous failure leading to the current debate over legalizing marijuana- Balance between individual desires and needs and society’s concern with the consequences of drug abuse.



Narcotic Drugs

  • Narcotic- Analgesic or pain-killing substance that depresses vital body functions such as blood pressure, pulse rate, and breathing rate. The regular administration of narcotics will produce physical dependence.

  • Analgesic- A drug or substance that lessens or eliminates pain.

  • Opium derivatives: Morphine, Heroin, Codeine derived from opium.

  • Opiates- not derived from opium but similar physiological effects

    • OxyContin – oxycodon for chronic pain- abused by 250,000!
    • Methadone- quelled addict desire for heroine. Now used for pain relief and is abused increasingly


Hallucinogens

  • Hallucinogen- A substance that induces changes in mood, attitude, thought, or perception.

  • Examples:

  • Marijuana- Cannabis sativa L.: most widely used illicit drug US

  • Hashish- sticky resin secretion extracted by soaking in a solvent such as alcohol

  • Sensemilla-potent form of marijuana- unfertilized flowering tops of female Cannabis plant

  • 43 million tried it, 50% addicted





Hallucinogens- Marijuana

  • Increased sense of well being

  • Dreamy carefree state

  • Vivid sense of touch, sight, smell, taste, sound

  • Hunger

  • Craving sweets

  • Not noticeably different from normal state



Other Hallucinogens

  • Lysergic acid diethylamide- LSD- derived from fungus ergot attacking grasses: Potent 25 ug lasts 12 hours

  • Mescaline

  • Phencyclidine (PCP)-clan labs: 1-6mg feelings of strength, and detachment. Soon unresponsive, confused and agitated… paranoia and depression

  • Psilocybin

  • Methylenedioxymethamphetamine- MDMA or ecstasy



Depressants

  • Depressant- a substance used to depress the functions of the central nervous system. Depressants calm irritability and anxiety and may induce sleep.

  • Alcohol: $40 billion annually US- most widely used and abused drug

  • Barbiturates: downers- relax and create a feeling of well being- 25 in use in medicine- 5: amobarbital, secobarbital, phenobarbital, pentobarbital and butabarbital used for most: “barbs, yellow jackets, blue devils and reds”

  • 10-70mg dose. Methaqualone (Quaalude) powerful sedative.

  • Tranquilizers: relax “without impairment”- Reserpine and chlorpromazine reduce anxiety of mental patients- mild tranquilizers- diazepam (Valium), chlordiazepozide (Librium) and meprobamate (Miltown) produce psychological and physical dependancy

  • Glue sniffing and gas propellants: exhilaration and euphoria- liver, heart and brain damage



Stimulants

  • Stimulant- A substance taken to increase alertness or activity.

  • Amphetamines: synthetic drug: uppers or speed: 5-20 mg. Amphetamine or Methamphetamine. Restlessness, instability and depression. Inject or smoke- Ice

  • Cocaine- Sigmund Freud experiments with drug- the need for food and sleep was completely banished. Once used for local pain killer. Powerful stimulant. Most commonly sniffed through mucus membranes of the nose. Crack smoked. Crack users rarely kick the habit. Abuse on the rise. Not harmless. - mental depression, cardiac arrest



Club Drugs

  • Club drugs- Synthetic drugs that are used at nightclubs, bars, and raves. Club drugs include, but or not limited to, MDMA (ecstasy), GHB (gamma hydroxybutyrate), Rohypnol (roofies), Ketamine, and Methamphetamine. MDMA

  • GHB-gamma hydoxybutyrate,

  • Rohyphnol (roofies)- muscle relaxation and loss of consciousness- rape drug

  • Ketamine

  • Methamphetame









Drug Identification

  • Selection of an Analytical Scheme.

  • Factors including amount of substance to be analyzed, time available, and disposition of the analyzed material.

  • The general principles that are followed when developing an Analytical Scheme are as follows.

  • 1. Visual examinations remain the first method employed.

  • 2. Examinations must move from general to specific.

  • 3. The schemes and processes must adhere to generally accepted processes and tests accepted in the field.

  • 4. Whenever possible perform at least one specific test.

  • 5. Pay attention to the possibility that the sample may be needed as an exhibit in court.

  • 6.If there is not enough material for a complete battery of tests those that do not destroy the sample should be performed first.

  • 7. Use the tests that have the most telling results.



Drug Identification

  • Screening test- A test that is nonspecific and preliminary in nature to reduce the possibilities to a manageable number- series of color tests.

  • Once the number of possibilities has been substantially reduced, the second phase of analysis must be devoted to pinpointing and confirming the drug’s identity

  • Confirmation- A single test that specifically identifies a substance.



Drug Identification tests

  • Color tests

  • Microcrystalline tests

  • Chromatography- TLC

  • Spectrophotometry- UV Spec, IR Spec

  • Mass spectrometry- coupled to GC: GC-MS





Color tests

  • Marquis (2 % formaldehyde in sulfuric acid): Purple- heroin, morphine and opium derivatives. Orange brown for amphetamines and methamphetamines

  • Dillie-Koppanyi (1% cobalt acetate in methanol followed by 5% isopropylamine in methanol)- Violet-blue for barbituates

  • Duquenois-Levine (A= 2% vanillin and 1% acetaldehyde in EtOH- B= concentrated HCL and C= chloroform) Purple in C layer for marijuana

  • Van Urk (1% p-dimethyaminobenzaldehyde in 10% concentrate HCl and EtOH). Blue purple- LSD

  • Scott Test (A=2% cobalt thiocyanate dissolved in H20, B= HCl and C=Chloroform) Cocaine – A blue, B pink and C blue reappears



Microcrystalline Tests

  • Microcrystalline tests- Tests to identify specific substances by the color and morphology of the crystals formed when the substance is mixed with specific reagents.



Chemical Microscopy

  • Reagents are aqueous solutions of metallic salts

  • Drug materials form complexes with reagent

  • Complexes are crystals

  • Observed microscopically

  • Closely related materials give very different crystals, easily distinguished











UV and Visible Spectrophotometry

  • Measures the absorbance of UV and visible light as a function of wavelength or frequency

  • UV spec of heroin has max absorption at 278nm providing materials probable identity

  • Will not provide definitive result - other material may have a similar UV absorption



IR Spectrum

  • IR specs provide far more complex patterns

  • Different materials always have distinctively different IR spectra

  • Each IR spectra is equivalent to a “fingerprint” of that substance and no other

  • Fourier transform infrared spectrophotometer FT-IR

  • Considered specific in itself for identification



GC- Mass Spectrometry



Collection and Preservation of Drug Evidence

  • Simple task with minimal precautions

  • Properly packaged and labeled

  • Prevent loss and cross contaminations

  • Volatiles in airtight container

  • Marked with information to ensure identification for future legal proceedings and to establish the chain of custody

  • Helps to have background information and any test results completed in the field



Summary 1

  • Drug is a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other higher order animals

  • Narcotic- Analgesic or pain-killing substance that depresses vital body functions such as blood pressure, pulse rate, and breathing rate. The regular administration of narcotics will produce physical dependence. Examples are the opium derivatives and opiates

  • Hallucinogen- A substance that induces changes in mood, attitude, thought, or perception. Examples are marijuana, LSD, PCP and MDMA



Summary 2

  • Depressant- a substance used to depress the functions of the central nervous system. Depressants calm irritability and anxiety and may induce sleep. Examples are alcohol, barbituates, tranquilizers and glue sniffing

  • Stimulant- A substance taken to increase alertness or activity. Examples are amphetamines and cocaine

  • Club drugs- Synthetic drugs that are used at nightclubs, bars, and raves. Club drugs include, but or not limited to, MDMA (ecstasy), GHB (gamma hydroxybutyrate), Rohypnol (roofies), Ketamine, and Methamphetamine. MDMA

  • Anabolic steroids- Steroids that promote muscle growth. Chemically related to male sex hormone, testosterone.



Summary 3

  • Controlled substances schedules are a legal drug classification system to prevent and control drug abuse

  • There are 5 schedules with I and II being the most dangerous with accordingly the highest penalties for manufacture, sale or possession

  • Drug chemists conduct screening tests to narrow down the possibilities and then confirmatory tests to identify the drug. Typically FTIR or GCMS is used

  • Collection of drug evidence should be done to prevent loss, and contamination. All evidence should be marked and chain of custody established.





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