TY  - JOUR
AU  - Jedlovszky-Hajdú, Angéla
AU  - Csákiné Tombácz, Etelka
AU  - Nyergesné Illés, Erzsébet
AU  - Bica, D
AU  - Vékás, L
TI  - Magnetite nanoparticles stabilized under physiological conditions for biomedical application
JF  - PROGRESS IN COLLOID AND POLYMER SCIENCE
J2  - PROG COLL POL SCI
VL  - 135
PY  - 2008
SP  - 29
EP  - 37
PG  - 9
SN  - 0340-255X
DO  - 10.1007/2882_2008_111
UR  - https://m2.mtmt.hu/api/publication/1238029
ID  - 1238029
AB  - The biomedical application of water based magnetic fluids (MFs) is of great practical importance. Their colloidal stability under physiological conditions (blood pH ∼ 7.2-7.4 and salt concentration ∼0.15 M) and more in high magnetic field gradient is crucial. Magnetite or maghemite nanoparticles are used in general. In the present work, magnetite nanoparticles were stabilized with different compounds (citric acid (CA) and phosphate) and sodium oleate (NaO) as the most used surfactant in the stabilization of MFs. The adsorption and overcharging effect were quantified, and the enhancement in salt tolerance of stabilized systems was studied. Adsorption, electrophoretic mobility and dynamic light scattering (DLS) measurements were performed. The electrolyte tolerance was tested in coagulation kinetic measurements. Above the adsorption saturation, the nanoparticles are stabilized in a way of combined steric and electrostatic effects. The aim was to research these two important effects and demonstrate that none of them alone is enough. The phosphate was not able to stabilize the ferrofluid in spite of our expectation, but the other two additives proved to be effective stabilizing agents. The magnetite was well stabilized by the surface complexation of CA above pH ∼ 5, however, the salt tolerance of citrate stabilized MFs remained much below the concentration of physiological salt solution, and more the dissolution of magnetite nanocrystals was enhanced due to Fe-CA complexation in aqueous medium, which may cause problems in vivo. The oleate double layers were able to stabilize magnetite nanoparticles perfectly at pH ∼ 6 preventing particle aggregation effectively even in physiological salt solution. © 2008 Springer-Verlag.
LA  - English
DB  - MTMT
ER  -