AOAC SPDS ERP DECEMBER 15, 2017

I. Summary of the Method

The method is a straightforward chromatographic analysis for the identification and quantification of a number of cannabinoids in dried plant material. Sample prep involves dry grinding a large sample (5g) of dried plant material and pulling a sub-sample (~200mg) to be extracted in a single solvent (80% methanol), followed by filtration, dilution, and injection. The removal of chloroform from sample preparation is a key point of differentiation for the method. The chromatography is a gradient method carried out on a standard C18 column with detection via DAD at a single wavelength (220nm). Quantification is based on external standards, no internal standards were used. A number of method performance indicators are provided including linearity of external standards and selectivity. Most critically to the SMPR; LOQs, repeatability, and recovery are also provided for most of the required cannabinoids. Additionally, the results of a stability test and a partial factorial optimization were reported to provide justification for many of the method steps. The method also contains information about analysis of cannabis oil which is not being considered in this review.

II. Review of the Method Only:

II. Review of the Method Only 1. Does the applicability of the method support the applicability of the SMPR? If not, please explain what is missing. 2. Does the analytical technique(s) used in the method meet the SMPR? If not, please specify how it differs from what is stated in the SMPR. 3. Are the definitions specified in the SMPR used and applied appropriately in the method? If no, please indicate how the terms are used. 4. Does the method, as written, contain all appropriate precautions and warnings related to the method's reagents, components, instrumentation, or method steps that may be hazardous? If no, please suggest wording or option(s).

This method is capable of identifying, via retention time of external standards, and quantifying, via external calibration curve, cannabinoids in dried plant material.

Yes

Reproducibility as defined in the SMPR is not carried out, but Intermediate Precision data is presented. LOQ is calculated based on an EPA MDL procedure which appears to be quite similar to the AOAC recommended method.

The use of liquid nitrogen is proposed for sample prep in the supporting data section of the submission with no methodology or accompanying safety precautions. If this is the recommended process it deserves a clear description and incorporation in the body of the method.