Ferritin Encapsulation and Iron Bioavailability Science

Ferritin is a ubiquitous iron‐storage protein forming a hollow spherical nanocage capable of sequestering up to 4,500 iron atoms in a mineral core. The reversible assembly of ferritin subunits underpins strategies for encapsulating bioactive compounds and micronutrients, while the distinction between apo‐ (empty) and holo‐ (iron‐filled) forms enables tailored delivery or supplementation. Advances in disassembly–reassembly techniques, protein engineering and biomineralisation have expanded the use of ferritin as a carrier in food fortification, nutraceuticals and medicine. Central to this field is understanding how encapsulation affects digestive stability, cellular uptake pathways—often via endocytosis—and ultimately the bioavailability of iron. Integrating biophysical characterisation with cell culture and in vivo models has revealed the interplay between ferritin structure, processing conditions and dietary inhibitors such as phytic acid. These insights are driving the design of next‐generation iron supplements and functional foods to address global iron deficiency while minimising oxidative side effects.

Research from Nature Portfolio

Recent studies have demonstrated that iron loading in ferritin within pea seeds accumulates gradually throughout seed development, with iron‐bound ferritin localised at the periphery of starch‐rich plastids. Standard cooking destabilises the protein nanocage, releasing iron that is then sequestered by phytic acid, thereby impairing uptake in intestinal cell models. By contrast, immature green peas, which contain lower levels of phytic acid, yield digestates in which ferritin‐bound iron remains more intact and is more efficiently internalised, highlighting the crucial role of inhibitory dietary components in modulating iron bioavailability.

Ferritin Encapsulation and Iron Bioavailability Science publication trend

The graph below shows the total number of articles in ferritin encapsulation and iron bioavailability science across all publications each year (not limited to Nature Index journals).

Technical terms

Ferritin: A 24‐subunit protein forming a nanocage that stores iron as a mineral core.

Apoferritin: The empty protein shell of ferritin, devoid of its iron core, used for encapsulation of guest molecules.

Holoferritin: The iron‐loaded form of ferritin that serves as a depot for dietary iron supplementation.

Bioavailability: The proportion of ingested nutrient or compound that is absorbed and made available for physiological functions.

Endocytosis: A cellular process by which intact ferritin molecules are internalised into cells via vesicle formation.

References

1. A Dual Function of Ferritin (Animal and Plant): Its Holo Form for Iron Supplementation and Apo Form for Delivery Systems. Annual Review of Food Science and Technology (2023).
2. Effects of heat treatment on the structure, digestive property, and absorptivity of holoferritin. Food Innovation and Advances (2023).
3. Ferritin Nanocage: A Versatile Nanocarrier Utilized in the Field of Food, Nutrition, and Medicine. Nanomaterials (2020).
4. Synthesis of homogeneous protein-stabilized rutin nanodispersions by reversible assembly of soybean ( Glycine max ) seed ferritin. RSC Advances (2015).
5. Pea Ferritin Stability under Gastric pH Conditions Determines the Mechanism of Iron Uptake in Caco-2 Cells. Journal of Nutrition (2018).
6. The stage of seed development influences iron bioavailability in pea (Pisum sativum L.). Scientific Reports (2018).