NOW® Develops Testing Method for Pesticide Residue

Anticipates Application to Additional Herbal Extracts

NOW® scientists have addressed one of the challenges in testing herbal extracts for pesticide residue by publishing a test method they developed for the analysis of pesticide residues in challenging botanicals, such as hawthorn extract. Botanical extracts present a challenge when analyzing pesticide residues by gas chromatography – tandem mass spectrometry (GC-MS/MS) due to concentration of the matrix during the extraction process. While QuEChERS extraction paired with solid-phase extraction (SPE) step has proven to be very useful for routine analysis, certain extracts with greater matrix effects are still challenging. Standardized Hawthorn extract powder was chosen for this study, as its analysis exhibits a high degree of matrix interferences.

NOW scientists investigated utilization of C18E d-SPE cleanup in addition to the standard QuEChERS and SPE sample cleanup procedure. The method modification reduced the total number of non-analyzable compounds (due to chromatographic interferences) from 35 to 19. The method modification improved pesticide detection in hawthorn extract, and the NOW scientists believe the modification will also improve the method performance in other botanical extracts with similar chromatographic challenges.

“This is yet another example of our commitment to science in the ongoing quest to ensure that our customers have access to the highest quality ingredients and products,” said Aaron Secrist, Executive Vice President of Quality, R&D and Operations. “The great work done by our scientists is invaluable not only to NOW but to the greater industry as we make our research available to all. This type of work often times will be the launching board for others in the industry as they struggle with similar challenges. NOW is proud to be a resource to the dietary supplement industry to help raise the bar with regards to quality and safety, and also to the greater analytical community at large.”

NOW’s analytical pesticide team (Jerry Mueller, Camille Grigsby and Carlos Parra) developed the method and presented the research at the North American Chemical Residue Workshop (NACRW) on 7/27/2021.