4103 - lecture 1 - basic forensic analysis

Question 1

what is the first colour test you should always carry out?

Answer 1

marquis test

Question 2

what does the marquis test test for?

Answer 2

opiods, amphetamine family, alkaloids (cocaine) and magic mushrooms

Question 3

what colour does the marquis reagent turn in the presence of morphine/heroin?

Answer 3

purple

Question 4

what colour does the marquis reagent turn in the presence of magic mushrooms?

Answer 4

yellow

Question 5

what colour does the marquis reagent turn in the presence of ecstasy?

Answer 5

orange to black

Question 6

what colour does the marquis reagent turn in the presence of methamphetamine?

Answer 6

orange

Question 7

what colour does the marquis reagent turn in the presence of amphetamine?

Answer 7

orange-red-brown

Question 8

what is the formation of the marquis reagent?

Answer 8

mixture of 2% formaldehyde in sulphuric acid

Question 9

what is a limitation of the marquis reagent?

Answer 9

you cant differentiate between amphetamine and methamphetamine as the results are too similar, so you have to do another test

Question 10

what does the ehrlichs test test for?

Answer 10

lysergic acid diethylamide - LSD

Question 11

what colour does the ehrlichs test turn in the presence of LSD?

Answer 11

a blue/purple colour as it forms a tertiary carbocation

Question 12

what is the ehrlichs test composed of?

Answer 12

1% p-dimethylaminobenzaldehyde dissolved in concentrated HCl in ethylacetate

Question 13

what kind of reaction is the ehrlichs test?

Answer 13

condensation reaction

Question 14

what does the duquenois-levine test for?

Answer 14

delta-9-tetrahydrocannabinoil - THC

Question 15

what are the steps in the duquenois-levine test?

Answer 15

1. add 2% vanillin and 1% acetaldehyde in ethanol
2. concentrated HCl
3. chloroform

Question 16

what is the positive result for the duq test?

Answer 16

purple

Question 17

what is the fast blue bb salt test used for?

Answer 17

differentate between thc and the metabolites cannabinol/cannabidol, based on azo dye formation

Question 18

after cannabis is extracted into chloroform and bb salt is added, what colour will THC/cannabinol/cannabidol turn?

Answer 18

THC - red
cannabinol - purple
cannabidol - orange

Question 19

what does the cobalt thiocyanate test test for?

Answer 19

cocaine

Question 20

what is the cobalt thiocyanate reagent formed of?

Answer 20

2% cobalt thiocyanate in conc HCl

Question 21

what colour does the ion pair become in the cobalt thiocyanate test?

Answer 21

the ion pair becomes blue

Question 22

what is the dille-koppanyi test for?

Answer 22

barbituates

Question 23

what is the formation of the dille-koppanyi reagent?

Answer 23

1% cobalt acetate in methanol
followed by 5% isopropylamine in methanol

Question 24

what colour does the transition metal complex form for a positive result for barbituates in the dille-kppanyi test?

Answer 24

a violet-blue colour

Question 25

what is the simon test used for?

Answer 25

used to differentiate methamphetamine (secondary amine) from amphetamine (primary amine)

Question 26

what is the name of the complex that is formed with the simon test?

Answer 26

simon-awe complex

Question 27

if the drug tested using the simon test is methamphetamine, what is the solution that is formed and what colour is it?

Answer 27

2% nitroprusside solution, containing acetaldehyde blue solution

Question 28

if the drug tested using the simon test is amphetamine, what is the solution that is formed and what colour is it?

Answer 28

2% nitroprusside solution containing acetone purple solution

Question 29

what is the libermann's test for?

Answer 29

to target phenol and amine functional groups found in drugs (amphet / paracetemol contain these functional groups)

Question 30

what does the ferric chloride reagent test for?

Answer 30

salicylates, alkaloids and phenols

Question 31

what colour gives a positive result for the ferric chloride test?

Answer 31

yellow/orange

Question 32

what does the frohede test test for?

Answer 32

codeine/opium/LSD and others

Question 33

what is the positive result colour for the frohede test?

Answer 33

blue

Question 34

what is the mandelins reagent used for?

Answer 34

steroids, alkaloids and aspirin

Question 35

what colour is a positive result with the mandelins reagent?

Answer 35

green

Question 36

how do you carry out the test with amalic reagent?

Answer 36

1. add a few drops of amalic, the sample, and a few drops of potassium chlorate crystals to the crucible 2. evaporate on hot plate in fume hood, to dryness 3. add 2-3ml of ammonium hydroxide

Question 37

what does the amalic reagent test for?

Answer 37

caffeine

Question 38

what colour is a positive result with the amalic reagent?

Answer 38

pink

Question 39

after using the regents to test a sample, what else can you do?

Answer 39

test the samples melting point and compare to literature values

Question 40

are these tests presumptive or confirmitive?

Answer 40

presumptive

Question 41

what would you have to do to then confirm the identity of a sample?

Answer 41

confirmative testing like GCMS/UV vis

Question 42

what is the most and least stable carbocation?

Answer 42

most - tertiary least - primary

Question 43

what do drugs produce when they interact with reagents?

Answer 43

coloured compounds - chromophores

Question 44

what are the examples of chromophores?

Answer 44

azo dyes transition metal complexes carbocations

Question 45

what does a chromophore do?

Answer 45

absorb and emit light in the visible region of the electromagnetic spectrum

Question 46

what happens when the marquis reagent reacts with methamphetamine?

Answer 46

it forms a primary carbocation

Question 47

how would you stabilise the primary carbocation that is formed when methamphetamine reacts with the marquis reagent?

Answer 47

add another molecule of methamphetamine