Abstract
Background: Relatively large disulfide-linked polypeptides can serve as signaling molecules for a diverse array of biological processes and may be studied in animal models to investigate their function in vivo. The aim of this work was to develop an LC–MS/MS assay to measure a model peptide, INSL3, in rat plasma. Results: A dual enrichment strategy incorporating both protein precipitation and solid phase extraction was utilized to isolate INSL3 from rat plasma, followed by targeted LC–MS/MS detection. The method was able to measure full-length INSL3 (6.1 kDa) down to 0.2 ng/ml with acceptable accuracy and precision. Conclusion: The final assay was applied to support an exploratory pharmacokinetic study to evaluate steady-state concentrations of dosed INSL3 in rat plasma.
Papers of special note have been highlighted as: • of interest; •• of considerable interest
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