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Drug Identification Tests. Catalyst – entrance quiz! Using your notes. Name two club drugs and their effects. Whats the difference between cocaine and crack cocaine?. Aim. What are the tests that forensic scientists use to determine the identity of drugs Agenda Catalyst Mini Lesson
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Catalyst – entrance quiz! Using your notes • Name two club drugs and their effects. • Whats the difference between cocaine and crack cocaine?
Aim • What are the tests that forensic scientists use to determine the identity of drugs • Agenda • Catalyst • Mini Lesson • Practice
Screening and Confirmation • 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?
Screening and Confirmation • When faced with a scenario like this, forensic scientists have to develop a plan of action. • Two phases • Screening phase • Confirmation phase
Screening test • 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
Why can screening tests not confirm identity? • Other drugs/chemicals might react in similar ways
Color Tests • 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!*
Marquis • Reagent purple in presence of heroin, morphine, opiates • Reagent orange/brown in presence of amphetamines and methamphetamine
Dillie-Koppanyi • Reagent violet/blue in presence of barbituates
Duquenois-Levine • Test for marijuana • Add a series of chemical solutions • Turns purple when chloroform is added
Van Urk • Reagent blue/purple in presence of LSD
Scott Test • Two steps! • Reagent blue in presence of cocaine • When add hydrochloric acid clear pink
example • Watch my mini experiment!
Phase Two: Confirmation • Confirmation test - a single test that specifically identifies a substance.
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.
Over the Counter Drug Lab February 21st, 2010
Catalyst • 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?
Aim • 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
Learning Target • I CAN describe AND perform the laboratory tests normally used to perform a routine drug identification analysis
Take 5 minutes to read the lab • Try to fill out the table
Safety precautions • 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.
When you are done • Wash out your materials in the sink. • Leave on papertowels to dry. • Return bottles/samples up to front
Lab questions due tomorrow • Try to complete them now • Complete sentences • Individually. • Be neat. Dont fold up your paper .
chromotography February 23rd, 2010
catalyst • 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?
Aim • What is chromotography? What is chromotography used for? • Agenda • Catalyst • Demo • Mini lesson • Practice
Demo • Watch my setup.
Chromotography • Way to separate and identify the components of a mixture • Useful for analyzing drug speciments that might be diluted or “cut”
Idea: chemical substances escape into surrounding environment • Example: nail polish • Liquid phase: liquid nailpolish in bottle • Gas phase: gaseous vapors of nailpolish in the air
Separation of mixtures • If you have salt water, how do you separate the salt and water?
Many types of chromotography • 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.
Thin Layer Chromotography (our focus) • Uses a solid stationary phase and a moving liquid phase to separate pieces of a mixture. • Quick and easy method • Need tiny sample
Show you demo online first, then i’ll explain the details • http://www3.wooster.edu/Chemistry/analytical/gc/default.html
Each piece of mixture is separated by polarity • If molecule is POLAR, will not travel far • If molecule is NONPOLAR, it will travel far.
Procedure • 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.
Most often parts of mixture are clear • So you have to use a different chemical reagent to show the color
Rf value • 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.
Rf value • Distance traveled by component distance traveled by liquid • example:
Rf value • Distance traveled by component distance traveled by liquid • example:
Homework • Your discussion questions in paragraph form • The mini worksheet i gave out now.
Catalyst • What is the equation for Rf value? • What is Rf value useful for? • How far the spot traveled • How far the liquid traveled
Catalyst • Write 3 sentences explaining what we did in the lab. • Im coming around to check if youve done this in 3 minutes.
Aim • How do we conduct TLC analysis • Write mini lab write up
Learning Target • I can describe, explain , and perform the process of chromatography
Rf Value Analysis • How do we do it? • Need ruler & calculator • Distance moved by substance • Distance moved by solvent