News & Events

When

Date - March 27, 2019
1:00 pm - 2:00 pm

What

MS Defense
Faculty Advisor: Dr. Nadja Cech
Talk Title: Identification of Adulteration in Botanical Samples with Untargeted Mass Spectrometry Metabolomics

Abstract:

According to the 2017 Council for Responsible Nutrition survey, botanicals makeup 39% of the total dietary supplement usage in the United States. The use of dietary supplements in general has increased by 8% since 2015, thus with a raise in botanical dietary supplement usage, there is a need to ascertain the authenticity and chemical composition of such products. Adulteration of dietary supplements has become a more prevalent issue as businesses ignorantly or deliberately sell products that do not match the taxonomy of the advertisement. This can be a health issue for consumers as well as possibly a much less effective product. A method for adulteration detection of botanicals utilizing untargeted mass spectrometry based metabolomics was standardized and implemented on multiple instrument platforms, including LC-UV, as well as Q-ToF and Orbitrap mass spectrometers. The outlier limitation was determined by combining two different plant species, Hydrastis canadensis L. (Ranunculaceae) and Coptis chinensis Franch. (Ranunculaceae), in different percentages to emulate different levels of adulteration. The methodology was effective on all instrument platforms, but the sensitivity varied. The detection limit at which the adulterated sample was statistically an outlier was measured using Hotelling’s T² 95% confidence interval. The outlier limitation for LC-UV, Thermo Q Exactive Plus, and Waters Synapt G2 Q-ToF were 50%, 10%, and 50% adulteration respectively. Each platform resulted in successful adulteration determination showing this method is viable across multiple platforms and detectors. A targeted analysis was also performed to show the contrast of a more quantitative approach and the reproducibility of the different mass analyzers. The targeted methodology was much more sensitive with a limit of detection (LOD) of 0.0047 µM, 0.025 µM, and 0.25 µM as well as a limit of quantitation (LOQ) of 0.12 µM, 0.55 µM, and 0.54 µM on Orbitrap, Q-ToF, and Photodiode array (PDA) detector platforms respectively. The concentration of palmatine, a characteristic marker of adulteration, was found to have a concentration of 0.16 ± 0.01 µM at 10% C. chinensis indicating a targeted methodology would successfully detect trace levels of adulteration.