Analysis Of Cannabinoids Flashcards
Give examples of cannabis samples that are used for analysis
Customs and border control services seizures
Seizure made by Royal Cayman Islands police service
Where do the majority of cannabis that we analyze in Canada come from?
Majority of cannabis is imported via boats from Jamaica, where it is cultivated outdoors
How are samples collected for analysis?
Take two random representative samples of the material from each bag
Collect samples of other vegetative matter such as banana or tobacco leaves
Seal two samples in a clean Ziploc bag and label
Transferred to a secure storage area at the lab
Weigh each garbage bag of cannabis material
What happens to samples when analysis is complete?
They returned to RCIPS where they are incinerated
Who can identify cannabis based on its morphological characteristics using microscopy alone?
Only a trained professional botanist
How are other examiners able to identify cannabis?
Must have extensive training and and obtained botanical competency, and they must use other tech techniques in addition to microscopy
Outline the six steps of the cannabis analysis
Visual examination
Olfactory examination [optional)
Weighing the samples
Microscopic examination
Colour test – optional
Qualitative analysis – GC-MS
What does the visual examination consist of?
Record observations of contents of exhibits, noting the number and the markings of all items and observe the sample characteristics
Give examples of of sample characteristics that would be noted in a visual examination
Vegetable matter
Dark resinous matter
Thick oily liquid
Compressed vegetable matter
What is a part of the visual examination that is conducted on herbal products
Note if there are male or female flower present, and if seeds or stalk material is present
What is an old factory examination?
Noting the odour of the sample
Describe the smell of cannabis
Sweet, pungent odour
Skunky
Smell permeates from the room and get into your clothes and hair
Outline the process of weighing the sample
Use certified weights on an electronic balance and make sure to check calibration
If material is visually similar, combine the herbal or resinous material together and weigh together
Obtain a printout of the weight
What type of light microscopy is usually suitable for observing the relevant botanical features on herbal cannabis
Low powered microscopy
20 or 40 times magnification
What must be done if no observations can be made under 20 or 40 times magnification
The sample that must be examined under high-powered light microscopy
400 or 1000 times magnification
What is the minimum amount of things that must be identified for herbal cannabis during the microscopic examination?
You glandular trichomes with attached head must be identified +2 types of hairs if possible
Is a microscopic examination required for oils?
No
What type of documentation needs to be done for the microscopic examination?
Photographs
Record observations by either low or high-powered microscopy on the cannabis examination form
What is the modified Duquenois-Levine test
A screening test for marijuana
When was the D-L test developed and by who?
In the 1930s by Pierre Duquénois
How do you prepare the Duquenois reagen
Add 2 g of vanillin and 2.5 mL of acetaldehyde to 100 mL of ethanol
Outline the seven steps of the D-L test
Add approximately 20 to 50 mg of sample in a glass test tube
Add three drops of the reagent and shake
Add three drops of concentrated hydrochloride and shake
Note any colour change?
Add 1 mL of CHCL3 and vortex
Allowed to settle and separate into two layers
A purple colour transfers into the organic layer indicates marijuana
Why must the results of the D-L test be verified using a second independent analytical method
Due to issues with the D-L test giving false positive results with other plant materials
What is a common confirmation method after using the D-L test?
GC-MS
What is identified by GC-MS
THC is identified
Other cannabinoid’s like CBN or CBD may also be identified
What must be kept in mind regarding age of sample for GC-MS testing
Older cannabis samples have potential problems with the THC degrading and may not be identified
In these instances, the identification must be based on the identification of either CBD or CBN
Outline the process of qualitative drug analysis four steps
Place approximately 50 to 75 mg of a random herbal cannabis sample into a GC-MS auto sampler vile. Sample smaller amounts for cannabis, resin or cannabis oil.
At approximately 1 mL of methanol
After a five minute extraction. Remove the subsequent solution, leaving behind the unsolved plant material.
Transfer sample solution to a new autosampler, vile, cap it and analyze by GC-MS
What does GC-MS stand for?
Gas chromatography mass spectrometry
Outline the Cayman Islands misuse of drugs act
Buying, selling, possessing, producing, consuming, distributing or storing of cannabis is illegal unless under prescription
List some companies or individuals who might undergo urine analysis
Public transport
RCIPS
Department of community rehab rehabilitation
Student
Athletes
What is the typical temperature range for urine?
32 to 38°C
Are any preservatives required to preserve urine samples?
No
What must happen to a sample that received a positive result from a urine screen analysis for THC?
A positive result must always be confirmed by GC-MS
Why might a urine screen analysis for THC produce a false positive?
From cross reactivity with unrelated drugs
What is the expected normal range for urine pH values
4.5 to 8.9
What happens if a a pH value is obtained during screening that is outside of the expected normal range
Must be retested to confirm using a pH metre
Besides drugs, what else is checked in a urine screen analysis (three)
Creatinine
P
H
Oxidants
Describe how specimen validity testing authenticates a negative test result from a urine screen analysis
The negative result obtained together with evaluation of creatinine, specific gravity, pH, and the possible presence of oxidants are used to ensure the integrity of the urine sample
How might someone try to beat a drug test?
Commercial and household products might be taken to try to dilute the specimen, cause the chemical breakdown through ingested substances, or added to the specimen, or attempt to substitute another substance for their own urine
What is creatinine?
A breakdown product of muscle protein metabolism found in the blood and removed by the kidneys into the urine
What is specific gravity testing?
Measures the concentration of particles in urine and the density of urine compared with the density of water
a refractometer measures the extent to which light is refracted through the liquid sample
What specific gravity testing result indicates a normal sample?
Result greater than 1.0030
What must be done if a creatinine value obtained during immunoassay screening is below 20 mg/dL?
The analysis must be repeated
If you retested a sample through immunoassay screening and the result is still less than 20 mg/dL, what must be done?
The sample must undergo a specific gravity test using a refractometer
What is indicated by an immunoassay screening result greater than 2 mg/dL and a specific gravity result less than 1.0030”
The sample is dilute
What factors may cause a urine sample to be dilute?
Ingestion of large amounts of water
Medical condition or medication
Adding water/liquid to a sample
What is indicated by an immuno assay screening results less than 2 mg/dL and a specific gravity result of less than 1.0010 or greater than 1.020?
A substituted sample
What is meant by a substituted sample?
The sample is not consistent with normal human urine
What is indicated by an amino acid result less than 2 mg/dL, a specific gravity result between 1.0010 and 1.020, and a pH between nine and 11?
Invalid sample
What is meant by an invalid sample?
There is a discrepancy between the creatinine and SPG results: they do not match, and the pH is higher than typically expected
What is indicated by samples with a pH value less than three or greater than 11?
Reported as adulterated sample
What is meant by an adulterated sample?
A urine specimen containing a foreign substance that is not a normal constituent of urine
List some common chemicals (oxidants) that are used to attempt to alter urine drug test results (seven)
Bleach
Iodine
Halogens
Nitrates
Chromates
Peroxide
Peroxidase
Should a positive result for oxidant activity be considered when interpreting drug results
Yes
What can the addition of oxidants to a urine sample cause?
Oxidants can cause decrease levels or negative results for certain drugs or metabolites
How can oxidants cause decrease levels or negative results for certain drugs or metabolites?
Either by masking the drugs presence or by causing the breakdown of the drug in the sample
Is the GC-MS instrument used for urine drug testing confirmation the same as that used for drug chemistry testing? Why or why not?
No
to avoid cross-contamination of samples and due to high levels, typically found in non-biological samples
What conclusion can be drawn if GC-MS detects THC-COOH?
Cannabis use within the last 30 days
List three judicial inquiries that aided in forensic method, development and validation for drug testing.
The Scarborough rapist investigation
The wrongful conviction of guy Paul Morin
The Gouge inquiry
How did judicial inquiries and the NAS report aid in forensic method development and validation for drug test testing?
They changed how analysis are performed, interpretation of data and language used in reports and during court testimony
Increased quality, control, and quality assurance practises for methods to increase the confidence in the results
Accreditation standards
What screening instrument does CFS use for THC screening?
ELISA
What volume of urine, blood or serum/plasma does ELISA need to run a test?
200 µL
What must a positive results obtained from ELISA undergo
Confirmation by a second independent analytical method, such as LC-MS/MS
True or false: THC GC-MS 2001 analysis uses both a blank and a positive control
False, a blank is used, but no positive control
How did THC GC-MS analysis change from 2001 to 2005? (Two).
Positive control was introduced
Five point calibration curve changed from one to 20 ng/mL to 1 to 40 ng/mL
How did THC analysis change in 2008?
Method moved from GC-MS to ESI LC-MS/MS with MRM
How did THC analysis change between 2008 and 2015? (3)
New instrument introduced: UPLC-MS/MS with MRM and new LC column introduced
Sample size reduced from 1 mL to .5 mL
Runtime shortened from 12 to 8 minutes minutes
How was the UPLC-MS/MS with MRM method updated in 2018 to conduct cannabinoid analysis?
In addition to Delta nine-THC and THC-COOH, now includes cannabadiol, cannabinol and THC-OH
When was Bill C-46 introduced
June 21, 2018
What was the purpose of Bill C-46?
Created per se limits for two drugs
What are the two per se limits for THC?
Between two and 5 ng/mL in blood
Over 5 ng/mL in blood
Outline the hybrid defence of alcohol and marijuana use
A combined per se offence of 2.5 ng/mL or more THC in combination with 50 mg per 100 mL or more of alcohol both in blood
True or false: measurement, uncertainty is a requirement for accreditation by a crediting bodies
True
What is measurement uncertainty?
A way of expressing the range of values that can reasonably be expected when the same measurement is repeated multiple times
Why is measurement uncertainty important?
No measurement is exact, but is an estimate of the true value
List some potential sources of measurementbuncertainty (five)
Procedure
Facility
Instrument
Process
Staff
How can instrument be a source of measurement uncertainty ((three))
Auto sampler syringe calibration
Software curve fitting
Integration algorithms
How can the process introduce a source of measurement uncertainty? (Four)
Matrix effects
Stability of standards
Certified reference material
Solvent purity
How many staff contribute to measurement uncertainty? (Five)
Training and measurement techniques
Variation in pipe padding or weighing
Attitude
How many procedure contribute to measurement uncertainty? (Two)
Staff training in the procedure
Clarity of procedure and instructions
How might the facility contribute to measurement uncertainty? [for)
Humidity
Temperature
Air flow
Lighting
List two potential issues with THC for drug testing
Issues with reproduceability and stability overtime
Postmortem redistribution issues
Why might THC concentration in blood, serum and urine decrease overtime?
Due to stability and/or adherence to glassware
For how long is THC stable in plasma at room temperature?
16 hours
For how long is THC stable in plasma at 5°C?
Two weeks
For how long is THC stable in plasma at -20°C? -80°C?
One month, three months
How much blood is lost in two weeks when stored in plastic tubes at room temperature and at -20°C?
20 to 30%, 25 to 75%
How long is fluoridated blood stored in poly propylene tubes stable for at room temperature, 4°C and -20°C?
One week, three months, six months
