Determination of motolimod concentration in rat plasma by liquid chromatography-tandem mass spectrometry and its application in a pharmacokinetic study.

•No validated method exists for quantitative analysis of motolimod in plasma.•A reliable LC–MS/MS method was developed for quantifying motolimod in rat plasma.•Motolimod showed non-linear pharmacokinetics in rat.•Motolimod is unstable in rat liver microsomes.