A calibration sample should behave enough like the unknown sample for the comparison to make sense. That can be difficult in hemp testing because the plant material already contains the target compounds. Mastellone and colleagues addressed the problem while developing an ultrasound-assisted cannabinoid extraction using eutectic solvents.
How they made the comparison
The authors exhaustively extracted the target compounds from portions of the matrices under study, then used those depleted materials for matrix-matched calibration. Their method was applied to different hemp materials and a commercial CBD oil and used liquid chromatography with a photodiode-array detector. Reported accuracy ranged from 82% to 118% in their validation.
What an analytical file should contain
Ask how the laboratory checked that the blank was sufficiently depleted, how it represented the specimen type, and which quality controls accompanied the batch. A neat standard can establish that a compound produces a signal. Matrix-matched performance data address how the tested material and preparation affect the measurement. The study’s accuracy figures belong to its own method and matrices.
Leave a Reply