Magnetite nanotubes are interesting for numerous applications, including magnetic resonance imaging, biological and molecular separation, arsenic removal and catalysis. Peptides, on the other hand, are molecules that make up proteins, and are able to self-assemble into nanostructures in environmental conditions. The EU-funded MAGNETOTUBE (1D magnetic nanostructures using mineralizing peptides) initiative aimed to create magnetic peptide-based nanotubes by exploiting their ability to self-assemble in water and their potential to mineralise magnetite or silica on their surface. MAGNETOTUBE selected short peptides for their ability to form nanotubes in water and their low cost, to be able to produce enough material. The researchers chose three peptides (diphenylalanine, AAAAAAK and lanreotide) and tested numerous parameters for each, including a range of pH conditions and reaction times. The researchers created two kinds of 1D magnetic nanostructures using two different self-assembling peptides. MAGNETOTUBE successfully created self-assembled peptide-based nanotubes composed of silica and iron oxide nanoparticles in ambient conditions. These results will help to gain insight into the mineralisation mechanisms used by certain bacteria to control the precipitation of magnetite chains in their cytoplasm. This will lead to more simple processes to form self-assembled magnetic nanotubes.
Magnetite, magnetic nanotubes, peptides, self-assemble, MAGNETOTUBE, biomineralisation