EPA 1633: Having Nonextrable Internal Standards (NIS) to Quantify Extractable Internal Standards (EIS)

To the community,

We are trying to implement EPA 1633 Draft 4: https://www.epa.gov/system/files/documents/2022-12/3rd%20Draft%20Method%201633%20December%202022%2012-20-22_508.pdf. As part of this method, we have to have non-extractable internal standards (NIS) quantifying extractable internals standards (EIS) (e.g.,  13C4-PFOS is NIS and used to quantify EIS 13C8-PFOS) through a response factor approach. 

However, we are struggling to find a way of coding how to have nonextrable internal standards (NIS) quantify extractable internal standards (EIS) using MassHunter Quantitative Analysis 10.0. Do we call the EIS surrogate compounds? Do we call NIS surrogate? How would MassHunter quantify EIS using a reponse factor approach and not a calibration line?

Or how do we code this?


Alex Haluska

University of Tuebingen

Was this helpful?