Unraveling the in vivo pharmacokinetic behavior of mPEG5-NH2 polymer in rats by UHPLC-MS/MS assay

As an important chemical reagent, methoxy polyethylene glycol amine (mPEG-NH 2 ) is widely used in biomedical field. Unraveling the pharmacokinetic behavior of mPEG-NH 2 polymers is essential for revealing the toxicity and efficiency of mPEG-NH 2 related drug delivery systems. In this study, a simple analytical assay based on mass spectrometry (MS) was first established and validated for quantification of mPEG 5 -NH 2 in biological matrix. The multiple reaction monitoring (MRM) transitions at m / z 252.2 (precursor ions) → 87.7 (fragment ions) and m / z 371.2 (precursor ions) → 89.2 (fragment ions) were chosen to determine mPEG 5 -NH 2 and OH-PEG 8 -OH, respectively. The UHPLC-MS/MS assay showed excellent linearity over the range of 0.01–10 μg/mL. Intra-day and inter-day accuracies and precisions of the assay were all within ± 6.44 %. The analytical assay was successfully applied to reveal the in vivo pharmacokinetic behavior of mPEG 5 -NH 2 in rats.