Zwitterionic moieties from the Huisgen reaction: a case study with amphiphilic dendritic assemblies

Supramolecular nano-assemblies that reduce nonspecific interactions with biological macromolecules, such as proteins, are of great importance for various biological applications. Recently, zwitterionic materials have been shown to reduce nonspecific interactions with biomolecules, owing both to their charge neutrality and their ability to form a strong hydration layer around zwitterions via electrostatic interactions. Here, new triazole-based zwitterionic moieties are presented that are incorporated as the hydrophilic functionalities in facially amphiphilic dendrons. The amphiphilic zwitterionic dendrons spontaneously self-assemble in aqueous solutions forming micelle-type aggregates, which were confirmed by DLS, TEM, and fluorescence techniques. The structural and functional characteristics of the zwitterionic dendrons are also compared with the corresponding charge-neutral PEG-based dendrons and anionic carboxylate-based dendrons. Surface-charge measurements, temperature sensitivity and evaluation of interactions of these assemblies with proteins form the bases for these comparisons.