Dendronized Hyperbranched Polyethyleneimines with Switchable Thermoresponsiveness and Encapsulation

Abstract

Hyperbranched polyethyleneimines (PEIs) with multiple layered structures and high density of terminal amino groups have shown great potentials for applications in biomedicine, sensors, and catalysis. In this work, a kind of dendronized hyperbranched PEIs (DHPs) was synthesized by modification of PEIs with dendritic oligoethylene glycols (OEGs). These DHPs not only inherit the characteristic thermoresponsive behavior from the OEG dendrons, but also show low cytotoxicity and switchable encapsulation capacities. Their thermoresponsive behavior was found to be mainly dependent on the coverage and amphiphilicity of dendritic OEGs, solution pH, and NaCl concentration. Moreover, DHPs exhibit advantages in thermally‐switchable complexation with guest molecules because of their adjustable crowding effect from the densely packed OEG chains. In addition, these DHPs can also be used as nanoreactors, which can reduce metal ions into metal nanoparticles in a convenient way. In virtue of these peculiarities, we believe these dendronized hyperbranched PEIs with smart properties can be used as promising scaffolds in drug‐controlled release and nanoreactors.This article is protected by copyright. All rights reserved