The ferritin superfamily: Supramolecular templates for materials synthesis

Abstract

Members of the ferritin superfamily are multi-subunit cage-like proteins with a hollow interior cavity. These proteins possess three distinct surfaces, i.e. interior and exterior surfaces of the cages and interface between subunits. The interior cavity provides a unique reaction environment in which the interior reaction is separated from the external environment. In biology the cavity is utilized for sequestration of irons and biomineralization as a mechanism to render Fe inert and sequester it from the external environment. Material scientists have been inspired by this system and exploited a range of ferritin superfamily proteins as supramolecular templates to encapsulate nanoparticles and/or as well-defined building blocks for fabrication of higher order assembly. Besides the interior cavity, the exterior surface of the protein cages can be modified without altering the interior characteristics. This allows us to deliver the protein cages to a targeted tissue in vivo or to achieve controlled assembly on a solid substrate to fabricate higher order structures. Furthermore, the interface between subunits is utilized for manipulating chimeric self-assembly of the protein cages and in the generation of symmetry-broken Janus particles. Utilizing these ideas, the ferritin superfamily has been exploited for development of a broad range of materials with applications from biomedicine to electronics.

Magnetic Birefringence Study of the Magnetic Core Structure of Ferritin

“…Recently it was shown that the hollow structure of apoferritin can be exploited as an excellent reaction vessel for nanoscale synthesis of dierent minerals. Up to date many compounds have been synthesised within this protein cage [1,2] and potential applications in electronics and biomedicine were discussed [35]. The ferritin-mineral complex with a magnetite (or a maghemite) as a core mineral, is called magnetoferritin (MFer) [1].…”

Physiological origin of biogenic magnetic nanoparticles in health and disease: from bacteria to humans

“…In particular, magnetite and/or maghemite have been synthesized in vitro inside apoferritin to produce a novel material known as magnetoferritin. Further development of this biomimetic way of nanosynthesis within the ferritin cavity 181,182 has allowed the production of ferritin with various cores, as illustrated in Figure 10. In general, HSF is used as the starting material for preparation of apoferritin, which is used as a nanoreactor.…”

Hybrid Ferritin Nanoparticles as Activatable Probes for Tumor Imaging

“…Each ferritin molecule is made of 24 subunits, which are self-assembled, in a noncovalent fashion, into a cagelike nanostructure. [25] Such an intriguing architecture of ferritins has attracted previous research interest in their use as nanoreactors to synthesize nanomaterials. [26][27][28] Their potential in the field of optical imaging, however, has seldom been studied.…”