Succinylated Polyethylenimine Derivatives Greatly Enhance Polyplex Serum Stability and Gene Delivery In Vitro.

Polymeric materials provide particularly attractive scaffolds for the creation of supramolecular bioconjugates for the delivery of nucleic acids but typically lack the efficiency and biocompatibility to be clinically relevant. To address both issues, we produced zwitterion-like derivatives of polyethylenimine via succinylation of primary and secondary amines (zPEI). Polymers were generated with 9-55% of the amines modified (zPEI X, where X indicates the percentage of amines succinylated).

Particle Diffusion in Polymeric Hydrogels with Mixed Attractive and Repulsive Interactions.

All biogels are heterogeneous, consisting of functional groups with different biophysical properties arrayed on spatially disordered polymer networks. Nanoparticles diffusing in such biogels experience a mixture of attractive and repulsive interactions. Here, we present experimental and theoretical studies of charged particle diffusion in gels with a random distribution of attractive and repulsive electrostatic interaction sites inside the gel.