Hierarchical Self‐Assembly of PDMA‐b‐PS Chains into Granular Nanoparticles: Genesis and Fate

Abstract

The hierarchical self-assembly of an amphiphilic block copolymer, poly(N,N-dimethylacrylamide)-block-polystyrene with a very short hydrophilic block (PDMA10 -b-PS62 ), in large granular nanoparticles is reported. While these nanoparticles are stable in water, their disaggregation can be induced either mechanically (i.e., by applying a force via the tip of the cantilever of an atomic force microscope (AFM)) or by partial hydrolysis of the acrylamide groups. AFM force spectroscopy images show the rupture of the particle as a combination of collapse and flow, while scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of partly hydrolyzed nanoparticles provide a clear picture of the granular structure.

Albumin and Hyaluronic Acid-Coated Superparamagnetic Iron Oxide Nanoparticles Loaded with Paclitaxel for Biomedical Applications

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“…By using selective solvents, temperature or other stimuli it is then possible to control the self‐assembly of ABC and obtain a plethora of nanostructures ranging from spherical and worm‐like micelles to vesicles . Poly( N , N ‐dimethylacrylamide)‐ b ‐polystyrene (PDMA‐ b ‐PS) is one of those polymers, that already demonstrated the capability to form core–corona NP and hierarchical granular NP …”