Supramolecular polymer-based transformable material for reversible PEGylation of protein drugs

We herein developed a transformable mixing-type material for reversible PEGylation of protein drugs using a supramolecular backbone polymer, that is, polyrotaxane possessing both amino groups and PEG chains (PEG–NH(2)–PRX). We expected that PEG–NH(2)–PRX provides amino groups to interact with protein drugs on demand because the mobility of amino groups in PEG–NH(2)–PRX was high. In fact, PEG–NH(2)–PRX formed complexes with protein drugs efficiently compared to PEGylated amino-dextran (PEG–NH(2)–DEX), a control material fabricated with a macromolecular backbone polymer. Moreover, PEG–NH(2)–PRX markedly improved the stability of antibodies and prolonged the hypoglycemic effects of insulin without loss of bioactivity, compared to PEG–NH(2)–DEX. These findings suggest that the supramolecular material, PEG–NH(2)–PRX, is a promising reversible PEGylation material for protein drugs compared to macromolecular materials.