Stabilization of aqueous dispersions of poly(methacrylic acid)-coated iron oxide nanoparticles by double hydrophilic block polyelectrolyte poly(ethylene oxide)-block-poly(N-methyl-2-vinylpyridinium iodide)

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 514; pp. 32 - 37
• Main Authors: Woźniak, Edyta, Špírková, Milena, Šlouf, Miroslav, Garamus, Vasil M., Šafaříková, Mirka, Šafařík, Ivo, Štěpánek, Miroslav
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-02-2017
• Subjects: Aggregation; Colloidal stability; Polyelectrolytes; SAXS; Small-angle light scattering; Superparamagnetic iron oxide nanoparticles; Aggregation; Polyelectrolytes; Small-angle light scattering; Colloidal stability; Superparamagnetic iron oxide nanoparticles; SAXS
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2016.11.044

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•PMAA coated at SPIONs forms interpolyelectrolyte complex with PEO-QP2VP.•The PEO-QP2VP layer at PMAA@SPIONs suppresses formation of small SPION clusters.•The size of SPION aggregates in the μm range decreases by adding PEO-QP2VP.
Aqueous dispersions of poly(methacrylic acid)-coated superparamagnetic iron oxide nanoparticles (PMAA@SPIONs) and nanoparticles obtained by adding a layer of double-hydrophilic cationic block polyelectrolyte poly(ethylene oxide)-block-poly(N-methyl-2-vinylpyridinium iodide) (PEO-QP2VP) on PMAA@SPIONs were studied by a combination of static and dynamic light scattering, SAXS, transmission electron microscopy and atomic force microscopy, probing the structure of the SPION aggregates on the lengthscale from 1 to 103nm. Both SALS and AFM results indicate that adding a PEO-QP2VP layer to PMAA@SPIONs decreases the size of SPION aggregates formed in the dispersions. While TEM micrographs show that PEO-QP2VP@PMAA@SPION particles are less apt to form small clusters with the size of several tens nm compared to PMAA@SPION particles, the local clustering has no effect on the power law scattering behavior (I(q)∼q−1.4) of the SPION dispersions at longer lengthscales (tens to hundreds nm), which reflects mainly polydispersity of the aggregates.