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What ISTDs were used for pesticides? Other analytes?

Ryan Janis

What ISTDs were used for pesticides? Other analytes?

Posted : November 22, 2017 5:24 pm
Katherine Hyland
Member Moderator

Six deuterated pesticides were selected for use as internal standards. Ideally, a deuterated internal standard for each analyte would be optimal for addressing in-source suppression of each analyte. The cost of deuterated standards however, makes this practice prohibitively expensive, and also difficult to add more compounds to the list in the future. ISTD selection was based on ready commercial availability of the deuterated compound, and a distinct difference between the selected ISTDs in compound class and retention time. The chromatogram was divided into six sections based on the RT of each selected ISTD, and analytes were assigned to the ISTD based on chromatographic elution section. In this way, the number of ISTDs required is kept low but analytes are still assigned to an ISTD that well represents its experienced matrix suppression. Deuterated THC and Carboxy-THC were also employed for the potency analysis.

Posted : November 22, 2017 5:36 pm