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bioRxiv · 10.1101/042416

Preprint: A robust peptidomics mass spectrometry platform for measuring oxytocin in plasma and serum

Ole Kristian Brandtzaeg·Elin Johnsen·Hanne Roberg-Larsen·Knut Fredrik Seip·Siri Leknes·Elsa Lundanes·Steven Ray Wilson
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Abstract

Current approaches to measuring the cyclic peptide oxytocin in plasma/serum are associated with poor selectivity and/or inadequate sensitivity. We here describe a high performance nano liquid chromatography-mass spectrometry platform for measuring OT in human plasma/serum. The platform is extremely robust, allowing laborious sample clean-up steps to be omitted. OT binds strongly to plasma proteins, but a reduction/alkylation procedure breaks this bond, allowing ample detection of total OT. The method showed excellent quantitation properties, and was used to determine total OT levels to 0.5-1.2 ng/mL (evaluated with human plasma and cord serum). The method is compatible with accessible mass spectrometry instrumentation, finally allowing selective and easily comparable oxytocin measurements.

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Ole Kristian Brandtzaeg, Elin Johnsen, Hanne Roberg-Larsen, Knut Fredrik Seip, Siri Leknes, Elsa Lundanes, Steven Ray Wilson. 2016-03-04. Preprint: A robust peptidomics mass spectrometry platform for measuring oxytocin in plasma and serum. https://doi.org/10.1101/042416

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