Silica-coated superparamagnetic iron oxide nanoparticles: New insights into the influence of coating thickness on the particle properties and lasioglossin binding

Silica-coated iron oxide nanoparticles are of enormous importance in biotechnology, nanomedicine, and catalysis. The study demonstrates the significant influence of the coating thickness on the particle properties. Though slow magnetophoresis, a thinner shell leads to higher surface areas, lower isoelectric points, and higher magnetizations. However, thick layers prevent oxidation and lead to stabilization. The coating thickness influenced the binding of the cationic peptide lasioglossin, with a maximal loading of 0.23 g g⁻¹ for the smallest particles. This knowledge can be used to specifically design particles for usage with a cationic tag system in biotechnology or drug delivery with antimicrobial peptides.