EVIDENCE LIBRARY
What Retention Times Can Show About Pesticide Separation in Hemp Extracts
A bench study compared the retention of pesticides and cannabinoids to assess preparative chromatography.
In liquid chromatography, compounds leave the column at different times depending on how they interact with the column and solvent. Cuchiaro and colleagues compared the retention times of selected pesticides and cannabinoids to assess whether a preparative separation could collect desirable compounds in fractions with fewer contaminants.
Separation depends on which compounds overlap
When two compounds leave the column in clearly different windows, fraction collection can separate them. If a pesticide and cannabinoid overlap, collecting the desired cannabinoid may also collect the pesticide. A retention comparison helps identify where that problem could occur under the tested gradient and column conditions.
The study examined a benchtop process. Verifying remediation in a finished batch would require measuring the contaminants in the collected fractions or resulting product. The relevant evidence would include the original and final concentrations, the analytical method and the identity of the batch tested.