Throughout human history, traces of nanotechnology exploitation, although subconsciously, have been discernible while the nanotechnology remains a central domain for progress in the fields of medicine and pharmacology nowadays. Today, it continues to shape novel therapeutic approaches and enhance existing ones. Within the realm of nanotechnology, innovative new nanoparticle types with unique properties are evolving. One such property is superparamagnetism, exhibited by particles of certain iron oxides smaller than 15 nm. This property is crucial for their application in developing drug delivery systems, offering precise control over the release of therapeutic agents. Magnetic nanoparticles can be employed as carriers for active pharmaceutical ingredients or utilized as such directly for therapy. In this master's thesis, we have coated the surfaces of prepared magnetic nanoclusters with amorphous silica. The synthesis was achieved using the Stöber method, known for its simplicity and manageability. By adapting the Stöber method, we can synthesize mesoporous silica coatings on particle surfaces, offering distinct advantages in delivery system development. In the experimental part of the master thesis, we focused on the synthesis of various mesoporous silica coatings, investigating the effects of several process modifications on the final silica coating form, including the choice of base, organic solvent, and surfactant. We introduced functional groups onto the silica surface, such as amines and carboxyl groups, via reactions with functional alkoxysilanes. Finally, we attached polyethylene glycol molecules to the silica surface to further enhance particle biocompatibility and colloidal stability. By using a transmission electron microscope, we determined the coating of nanoclusters with mesoporous silica was successful. We confirmed it furthermore by measuring the hydrodynamic size of particles before and after coating with silica. We successfully coated the nanoclusters with mesoporous silica with radially aligned pores in six of eight set coatings. Silica coating of the remaining two syntheses did not include the desired radially aligned pores, furthermore, the nanoclusters formed aggregates. We confirmed the removal of ammonium nitrate from the silica coating and functionalization of silica coating by measuring the zeta potential of suspensions. Zeta potential also indicated whether the suspensions were electrostatically stabilized.
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