This procedure details how to properly prepare HPLC samples from cannabis flower material and oil material.
Scope
This applies to all flower and oil samples prepared at the Ionization Labs Austin laboratory and any customer sites performing HPLC analysis of cannabis extracts or flowers.
Responsibility
It is the responsibility of the user to ensure that a calibrated pipette and balance are available, as well as a functioning sonicator and -20 °C freezer when preparing flower samples.
Equipment:
Disposable gloves and safety glasses should be worn at all times when handling chemicals. Refer to Methanol MSDS in the event of skin or eye contact or inhalation.
Remove the lid of the 20 mL sample prep vial and tare the solvent filled vial on the balance without the cap.
If using an empty 20 mL sample prep vial and the bottle top dispenser: Remove the vial lid and place the empty 20 mL sample prep vial on the balance and tare the balance.
Add the suggested weight of isolate material to the tared 20 mL sample prep vial. After the addition is finished, promptly screw back on the cap to reduce solvent evaporation. Record the strain, date of preparation and exact mass in mg on the sample vial and in your notebook.
If using an empty 20 mL sample prep vial and bottle top dispenser, add 4 mL of methanol to the vial and product.
Vortex the vial for 15 seconds or until there is the complete dissolution of the isolate into the MeOH solvent.
Place the 20 mL vial in the sonicator for 10 minutes at ambient temperature, ensuring that the water level in the sonicator reaches to at least half of the solvent height to dissolve the sample.
After removing the sample from the sonicator, vortex and/or shake the extract vial.
Place the small vials in the sample prep holding tray, from left to right starting with the green vial, followed by the yellow, and then blue. Label the vials with the strain, weight, and date they were prepared.
Once sonication is complete, remove the sample prep vial from the sonicator and use the 1 mL syringe to draw up 1 mL of solution. Next, place a syringe filter on the syringe tip and dispense into the green cap vial.
Dispense liquid in the syringe into the open green cap vial, discard the syringe and syringe filter, and put the green cap back on. Vortex the vial briefly.
Discard the syringe and filter.
IMPORTANT: DO NOT reuse the syringe and filter as this will contaminate your samples
Set the micropipette to 40 uL and attach a clean tip.
Unscrew the green cap and prepare the pipette tip for transfer.
Draw up 40 uL and dispense the green cap solution three times into the green cap vial.
IMPORTANT: This is crucial for accuracy as methanol is not stable in a dry tip. 6.2. The pipette has two positions when moving the thumb downward.
The first position is for drawing up liquid.
The second, being all the way down, is for dispensing.
IMPORTANT: If the sample is drawn to the 2nd position, the pipette will have the wrong amount.
Transfer 40 uL from the green cap vial to the yellow cap vial. Ensure that all of the solution has been transferred by drawing up and dispensing the yellow cap vial solution three times. Cap both vials and shake or vortex the yellow vial well.
Discard the used pipette tip and attach a new one. Repeat steps 6 and 7 using the yellow cap vial and solution and transfer 40 uL of the yellow vial solution to the blue cap vial. Once again, ensure complete transfer by drawing up and dispensing the blue cap vial solution three times. Cap both vials and shake or vortex the blue vial well.