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-NH2) is widely used in biomedical field. Unraveling the pharmacokinetic behavior of mPEG-NH2 polymers is essential for revealing the toxicity and efficiency of mPEG-NH2 related drug delivery systems. In this study, a simple analytical assay based on mass spectrometry (MS) was first established and validated for quantification of mPEG5-NH2 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 mPEG5-NH2 and OH-PEG8-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 mPEG5-NH2 in rats.