Forensic Chemistry: Drug Analysis and Toxicology Flashcards
(24 cards)
What is the controlled substances act of 1970?
- Regulates the manufacuture, posession, and distribution of controlled substances
- Enforced by the DEA
- Classifies drugs into five schedules based on potential for abuse, medical use in treatment, safety or dependence liability
What are the schedue 1 drugs?
- No currently accepted medical use and a high potential for abuse
- Heroine
- LSD
- MDMA (Ecstasy)
- Marijuana (THC)
- Psilocybin (magic mushrooms)
- Peyote
What are the schedule II drugs?
High potential for abuse, but have accepted medical uses
- Cocaine
- Methamphetamine
- Oxycodone
- Fentanyl
- Morphine
- Methadone
- Codeine
- Amphetamine
- Pentobarbital
What are schedule III drugs?
Moderate to low potential for physical and psychological dependence. The abuse potential is lower than schedule I and II. but higher than schedule IV
- Ketamine
- Anabolic steroids
- Testosterone
- Tylenol with codeine
- Suboxone
What are schedule IV drugs?
Low potential for abuse and low risk of dependence
- Xanax
- Valium (Diazepam)
- Ativan (Lorazepam)
- Abien (Zolpidem)
- (Various benzodiazepines)
- Tramadol
What are schedule V drugs?
Lower potential for abuse than schedule IV and consist of preparations containing limited quantities of certain narcotics
- Cogh preparations with less than 200mg of codeine per 100 mL
- Lomotil
- Lyrica
- Motofen
- Parepectolin
What are the steps of controlled substance analysis?
(Essay question)
Observation and sampling
Screening
Extraction
Instrument analysis
Data interpretation
What does observation and sampling in CSA do?
- Sample collection
- Initial weighing
- Sampling plan
- All done by police
What is the function of screening in CSA?
Presumptive tests
3 categories of tests
* A + A or B or C
* OR
* 3 from B or C
Chemical spot tests
* Color tests
* Quick, cheap, and easy
Other tests
* ELISA
* Spectroscopy
* Melting point
What is the function of extraction/sample preperation in CSA?
- Substances are separated from the matrix (solvent extraction)
- This step is required for many analytical tests
- You add a solvent, let it incubate, and then filter it.
What are the characteristics of instrument analysis in CSA?
Confirmatory tests of substances in question
FTIR (Fourier transform infrared spectroscopy)
* First spectroscopic technique applied
GC-MS
* The “gold standard”
How does FTIR work?
Fourier transform infrared spectroscopy
* Light source: shines infrared light
* Splitting the light
* Absorbtion: IR interacts with the sample, different structures absord different parts of the light
* Creating a pattern: light beams come back together and create a pattern
* Fourier transform: The machine turns the pattern into a graph
* IR spectrum: the graph shows peaks representing a specific chemical bond
How does GC-MS work?
Gas chromatography mass spectrometry
GC: separates different compounds based on their interactions with columns
MS: breaks each compound into fragments with charges and seperates them (Ionization and seperation based on mass/charge)
What are the types of data interpretation in CSA?
Qualitative
* Goal: Identify unknown substances
Quantitative
* Goal: Determine the substance concentration
What are the three types of forensic toxicology?
Human performance toxicology
* Criminal behavior related to the effects of drugs
Postmortem forensic toxicology
* Drug-related cause and manner of death
Forensic drug testing
* Workplace, doping control in sports, probation and parole
What is the best biological sample to collect for toxicology screening?
Vitreous humor in the eye
What are the steps in forensic toxicology analysis?
- Sampling
- Screening
- Extraction
- Instrument analysis
- Data interpretation
What is pharmacodynamics?
pharmacodynamics
What the drug does to the body
* Used by drug recognition experts (DREs) to help law enforcement dentify the type of drug based on symptoms
–
* CNS depressants
* CNS stimulants
* Hallucinogens
* Dissociative Anesthetics
* Narcotic Analgesics
* Inhalants
* Cannabis
What is pharmacokinetics?
pharmacokinetics
What the body does to the drugs
* ADME
* Absorption: entering bloodstream
* Distribution: blood to tissues or tissues to blood
* Metabolism: structural changes in the drug occuring in the liver, kidneys, lungs, etc. to facilitate elimination
* Elimination: removal of drug from body
What is samping in forensic toxicology?
- Creating a sampling plan
- Done by police, medical examiner, doctor, drug testing facilities, etc.
What is screening in forensic toxicology?
Using color tests of body fluids to detect the presense of specific properties
Immmunoassay test: ELISA test
ELISA is sensitive, easy to automate, but is expensive
The ELISA uses antibodies that bind an analyte to identify and measure the amount of the analyte
What is extraction in forensic toxicology testing?
- Isolating the drug from the biological samples and drug mixtures
- 2 techniques: solvent extractions and solid phase extractions (SPE)
What is instrument analysis in foresic toxicology?
GC-MS
Carry the sample in the gas phase
Seperate the compound base on the coating on the column and temperature
LC-MS
Carry the sample in liquid phase
Seperate comound base on the coating on the column and solvent composition (A+B)
What is the purpose of forensic toxicology interpretation?
- Substance identification
- Substance quanitifcation (lethal, therapeutic, or toxic ranges)
- Effect of the substance (impact on behavior, physical state, or contribution to death)
- Time of use (when the substance was consumed)
- Pharmacokinesis
- Pharmacodynamics
