
Name two club drugs and their effects.

Whats the difference between cocaine
and crack cocaine?

What are the tests that forensic scientists
use to determine the identity of drugs

Agenda
› Catalyst
› Mini Lesson
› Practice

Scenario: A police officer stops a
motorist who is driving erratically and
notices a bag of white powder on the
front seat of the car. S/he has no idea
what it is. How can S/he figure it out?
When faced with a scenario like this,
forensic scientists have to develop a
plan of action.
 Two phases

› Screening phase
› Confirmation phase
The drug could be 1000+ commonly
encountered drugs (Rx too)
 Screening test – a preliminary test used
to reduce the number of possible
identities of an unknown substance
 Many of these = color tests.
 Shows what is possible and what it is not.
 DOES NOT CONFIRM IDENTITY


Other drugs/chemicals might react in
similar ways
Many drugs turn certain colors when
brought into contact with a chemical
reagent
 Chemical reagent – a substance used to
detect other substances
 **only for screening purposes!*

Reagent  purple in presence of heroin,
morphine, opiates
 Reagent  orange/brown in presence
of amphetamines and
methamphetamine


Reagent  violet/blue in presence of
barbituates
Test for marijuana
 Add a series of chemical solutions
 Turns purple when chloroform is added


Reagent  blue/purple in presence of
LSD
Two steps!
 Reagent  blue in presence of cocaine
 When add hydrochloric acid  clear
pink


Watch my mini experiment!

Confirmation test - a single test that
specifically identifies a substance.
Name of Test
Drug its testing Color itll
for
change if
positive

1st – make a table organizing the color
indicator tests

2nd – with a partner, write a scenarios
where unknown drugs were found. Then
write a 1 paragraph description of what
tests you would perform and what results
you might see.
What is an over the counter drug?
 What are examples of over the counter
drugs that people use pretty commonly
 What is the difference between a
screening test and a confirmation test?

What are other screening tests
performed on over the counter drugs?
 How do we perform these tests?


Agenda
› Catalyst
› Go over lab procedure
› Complete lab

I CAN describe AND perform the
laboratory tests normally used to perform
a routine drug identification analysis

Try to fill out the table
BEFORE
Aspirin
Alkaseltzer
Tylenol
Unknown
A
Unknown
B
WATER
UNIVERSAL
INDICATOR
HCl
Ferric
Nitrate
Wear goggles
 Do everything over paper towels
 If theres a spill, contact me.
 If i make someone in your group take a
time out, dont complain.

tests
ASPIRIN
ALKASELTZER
ACETOMINO
PHEN
UNKNOWN A
UNKNOWN B
Wash out your materials in the sink.
 Leave on papertowels to dry.
 Return bottles/samples up to front

Try to complete them now
 Complete sentences
 Individually.
 Be neat. Dont fold up your paper .

What happens when your jeans are too
long and you walk around in the snow
after a snowstorm and the snow has
begun to melt?
 What do your jeans look like once youve
gone inside?
 What do they look like when theyve
dried hours later?


What is chromotography? What is
chromotography used for?

Agenda
› Catalyst
› Demo
› Mini lesson
› Practice

Watch my setup.

Way to separate and identify the
components of a mixture

Useful for analyzing drug speciments that
might be diluted or “cut”

Example: nail polish
Liquid phase: liquid nailpolish in bottle
 Gas phase: gaseous vapors of nailpolish
in the air


If you have salt water, how do you
separate the salt and water?
Thin layer chromotography
 Gas chromotography
 Ultraviolet and visible spectophotometry
 Infrared spectophotometry
 Mass spectophotometry


All are ways to figure out components of
mixtures. Used across the board in allllll
the sciences.
Uses a solid stationary phase and a
moving liquid phase to separate pieces
of a mixture.
 Quick and easy method
 Need tiny sample


http://www3.wooster.edu/Chemistry/an
alytical/gc/default.html
If molecule is POLAR, will not travel far
 If molecule is NONPOLAR, it will travel far.

A thin plate covered in a special coating
(silica gel)
 Sample must be in a dissolved form
 One tiny sample placed on lower edge
of place, about 1 cm away from bottom
 Placed in a little bit of liquid. The liquid
moves up the plate  takes with it
certain dissolved parts.


So you have to use a different chemical
reagent to show the color
Each chemical will move up a plate the
same distance.
 Ex: cocaine always moves up to the
same level
 Ex: blue ink will always move up to the
same level.

Distance traveled by component
distance traveled by liquid
 example:

Distance traveled by component
distance traveled by liquid
 example:

Your discussion questions in paragraph
form
 The mini worksheet i gave out now.

What is the equation for Rf value?
 What is Rf value useful for?

How far the spot traveled
 How far the liquid traveled

Write 3 sentences explaining what we
did in the lab.
 Im coming around to check if youve
done this in 3 minutes.

How do we conduct TLC analysis
 Write mini lab write up


I can describe, explain , and perform the
process of chromatography

How do we do it?
› Need ruler & calculator
Distance moved by substance
 Distance moved by solvent

(i.e. That orange spot is above MO for
Methylene Orange)
 Step 2: Measure from the pencil line Ms.
Martin drew to the line YOU drew.

› This is your DENOMINATOR
Step 3: Measure from the pencil line Ms.
Martin drew to the DARKEST PART of the
streak.
 Step 4: Divide!
 Unknown 1 has TWO Rf values
 Unknown 2 has ONE Rf value.


Paragraph 1:
› what are the two phases of drug analysis
› which phase is Thin Layer Chromatography a
part of?
› Describe how thin layer chromatography is used

Paragraph 2:
› Describe how Thin Layer Chromatography
works?
› What ideas are they based on?
› How are components separated
› How is it calculated?

Aim
› What question are we tryhing to answer

Hypothesis
› If... Then... statement

Methods
› What did we do in the lab?
› Write it in past tense
› Can list it OR write it in paragraph form
› Avoid using he/she/i/ms. martin
Results - Data Table & Observations
 Rewrite the data table NEATLY on paper.
 Compile the observations of your group
members. Write them up neatly.

What did we try to do int he lab? How
did we do it?
 What was the Rf value for each of your
samples?
