Due to their properties, magnetic nanoparticles are widely used in many fields, including medicine, technology and environmental sciences. Particularly interesting are superparamagnetic iron oxide nanoparticles that are generally accepted as safe
for humans and the environment. At the same time, they can be relatively easily prepared in stable colloidal suspension. Such particles behave as non-magnetic materials
in absence of external magnetic field and consequently do not aggregate magnetically.
This master thesis represents the results of synthesis of superparamagnetic microparticles in form of rods (microrods) which are magnetically composed of a large number of small maghemite (chemical γ-Fe2O3) nanoparticles. In the master thesis I studied the effects
of changing various synthesis conditions on formation and colloidal stability
of anisotropic microstructures, coated with a layer of silicon dioxide (silica).
Then I functionalised their surface with 3,3-ionene bromide cationic polyelectrolyte.
Synthesis and complexation process was determined with optical and transmission electronic microscopy, vibrating-sample magnetometer, ζ-potentiometry potentiometric precipitation titration and organoleptically.
The results confirm the success of the synthesis of maghemite microrods
with superparamagnetic properties, coating their surface with silica and complexation with ionene polyelectrolytes.
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