Transcript Drugs: Analysis - Centralia College

Drugs: Analysis
Summary
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Analysis of Chemical Drugs
Instrumental Examination
Botanical Examination
Chemical Examination
White Powder or Pills
What are they?
Drugs > Chemical Exam
3 steps in processing unknown chemicals:
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Screening step
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Sample preparation step
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Confirmatory test
Drugs > Chemical Exam > Screening
Color Test
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Small amount of
chemical in spot plate
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Drop of color changing
reagent added
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Color change noted
Drugs > Chemical Exam > Screening
Color Test
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Several tests done at
same time.
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Adulterants or diluents
may affect color
Drugs > Chemical Exam > Screening
Microcrystal Test
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Small amount of sample
dissolved in solution.
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Test reagent added;
contains another chemical
that reacts with drug.
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Insoluble crystal formed.
Drugs > Chemical Exam > Screening
Microcrystal Test
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Shape of crystal suggests
type of drug.
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Impurities may cause
unusual crystal formation.
Drugs > Chemical Exam > Screening
Thin Layer Chromatography (TLC)
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Dot of drug placed at bottom
of paper or thin silica plate
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Bottom dipped in solvent;
solvent diffuses up plate
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Solvent carries drug up paper;
distance depends on drug
Drugs > Chemical Exam > Screening
Thin Layer Chromatography (TLC)
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Different solvents result in
different distances
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Some systems include
color change components
Drugs > Chemical Exam > Screening
UV Spectroscopy
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Sample dissolved in liquid;
placed in cuvette.
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A range of UV light
wavelengths are passed
through solution.
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Some light will pass through;
some light will be absorbed
Drugs > Chemical Exam > Screening
UV Spectroscopy
Different drugs create a different pattern
Drugs > Chemical Exam > Screening
Gas Chromatography
Similar to TLC; different chemicals will move at
different rates through a capillary.
Drugs > Chemical Exam > Screening
Gas Chromatography
The time it takes to pass through the capillary
gives an indication of which drug it is.
Botanical Examination
With botanical evidence, additional steps
can be added to the screening process.
Drugs > Botanical Exam
Marijuana
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Macroscopic Exam:
Leaf and stem structure
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Microscopic Exam:
Tiny hairs on leaf surface
Drugs > Botanical Exam
Marijuana (Resin ID)
Color test:
Tests for chemical THC
TLC:
Tests for chemical THC
Drugs > Botanical Exam
Peyote
Macroscopic Exam:
Look for cotton-like tufts
Test for alkaloids:
TLC & Gas chromatography
Confirming mescaline not necessary
Drugs > Botanical Exam
Mushrooms
Macroscopic Exam:
Can identify mushrooms
that contain psilocybin
Screen for psilocybin:
Color test, TLC, and
UV spectroscopy
Confirmed with MS and IR spec (later slides)
Drugs
Screening Summary
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All screening tests give an indication of
what the drug is.
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Since some drugs behave alike during
screening tests, confirmation of the drug
type is needed.
Drugs
Sample Preparation
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In many cases, the identity of the drug
must be confirmed for prosecution.
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Before identification, it must be separated
from other chemicals in the mixture
Drugs > Sample Preparation
Sample Preparation (Separation)
1.
Physical Separation: particles are
separated based on microscopic appearance.
2.
Dry Wash or Dry Extraction
Dry Wash: Liquid dissolves adulterants;
solid drug left behind
Dry Extraction: Liquid dissolves drug;
solid adulterants left behind
Drugs > Sample Preparation
Sample Preparation (Separation)
Liquid/Liquid Extraction:
3.
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Entire sample dissolved in aqueous (water)
liquid
Organic liquid (oil-like) mixed with solution
Organic liquid removes adulterants
Sample remains in aqueous layer
Confirmation Techniques
Heroin?
Confirmation identifies the specific type of drug.
Drugs > Confirmation
Mass Spectroscopy
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MS will smash a molecule into pieces
and measure the mass of the pieces.
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Every drug will break in a unique way,
creating a unique amount of pieces.
Drugs > Confirmation
Mass Spectroscopy
Drugs > Confirmation
Infrared Spectroscopy
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Similar to UV spectroscopy, except a
range of infrared light wavelengths are
passed through a sample.
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Some light passes through; some light
is absorbed.
Drugs > Confirmation
Infrared Spectroscopy
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Different drugs = different patterns
Pattern is specific to one drug