Acknowledgments
We thank Marjolein Neele and Eugenie Schrama (Maasstad Hospital) and Harry Wanschers (Medisch Spectrum Twente) for their analytical support. Chromsystems Instruments & Chemicals GmbH (Munich, Germany) is kindly acknowledged for the donation of the HPLC and UHPLC kits used in this study.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
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