Optically Active Spherical Polyelectrolyte Brushes with a Nanocrystalline Magnetic Core

Abstract

The unique properties of magnetic nanocrystals have triggered intensive research towards their effective functionalization and application in many technological fields. Although synthesis of magnetic colloids is being thoroughly studied, there is limited knowledge on the synthesis, characterization, and properties of magnetic polyelectrolyte spherical brushes. In the present work, the preparation of such hybrids and the subsequent formation of stable aqueous colloids are described. The core of the spherical brush consists of a magnetic γ‐Fe2O3 nanocrystallite (faceted but mostly spherical‐like) with a mean diameter of 17 nm. The bioadhesive polyelectrolyte poly(sodium 4‐styrene sulfonate), forming the surrounding brush layer, was proven to be an effective covalently modifying macromolecule for the iron oxide surface, as Fourier transform IR spectroscopy revealed. Several observations on colloidal aspects are discussed and are successfully explained by models and experiments describing polyelectrolyte brushes with a soft polymeric core. Finally, the hybrids exhibit their multifunctional character and their technological importance by combining in a single and soluble product with magnetic and nonlinear optical properties.

Merging High Doxorubicin Loading with Pronounced Magnetic Response and Bio‐repellent Properties in Hybrid Drug Nanocarriers

“…The synthesis of MagP(MAA ‐g‐ EGMA) hybrid system employed alkaline hydrolytic condensation of a single ferrous precursor into MIONs21, 40 in presence of the surface functionalizing polymer p(MAA ‐g‐ EGMA) (see Figure and Table 1 for structural details), which reacted with MIONs by a simple self‐assembly process 41. The methacrylic acid monomers interact during nanocrystallites’ growth through the carboxylate groups with the Fe ions situated on the MION's surface.…”

Immobilization of magnetic iron oxide nanoparticles on laponite discs – an easy way to biocompatible ferrofluids and ferrogels

“…The solution was then washed twice with 50 ml of the distilled water and the final precipitate was the left to dry in air spreading it on a glass plate. Maghemite formation takes place after the initial formation of green ferrous hydroxides (and oxohydroxides) through solution reconstructive transformation, dehydration, and condensation reactions [43, 44]. …”

Synthesis and Magnetic Properties of Fe3O4 Nanoparticles Coated with Biocompatible Double Hydrophilic Block Copolymer

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