Experimental and mechanistic issues on the preparation of iron oxide nanoparticles stabilized

PAULA NICOLÁS; MARTÍN SALETA; HORACIO TROIANI; ROBERTO ZYSLER; VERÓNICA LASSALLE; MARÍA LUJÁN FERREIRA

ACTA BIOMATERIALIA

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2012 p. 4754 - 4762

1742-7061

Nanoparticles (NPs) with magnetic properties based on magnetite (Fe3O4, MAG) modified with oleic acid 27(OA), chitosan (CS) and bovine serum albumin (BSA) have been prepared. A versatile method of synthesis 28was employed, involving two steps: (i) co-precipitation of MAG; and (ii) nanoprecipitation of macromol- 29ecules on as-formed MAG NPs. Experimental variables have been explored to determine the set of con- 30ditions that ensure suitable properties of NPs in terms of their size, functionality and magnetic 31properties. It was found that the presence of OA in Fe+2/Fe+3 solutions yields MAG NPs with lower aggre- 32gation levels, while increasing initial amounts of OA may change the capability of NPs to disperse in aque- 33ous or organic media by modifying the stabilization mechanism. Incorporation of CS was verified through 34Fourier transform IR spectroscopy. This biopolymer stabilizes NPs by electrostatic repulsions leading to 35stable ferrofluids and minimal fraction of recoverable solid NPs. BSA was successfully added to NP formu- 36lations, increasing their functionality and probably their biocompatibility. In this case too stable ferrofl- 37uids were obtained, where BSA acts as a polyelectrolyte. From the proposed methodology it is possible to 38achieve a wide range of NPs magnetically active intended for several applications. The required proper- 39ties may be obtained by varying experimental conditions.