Milk protein-based hydrogels: Development and biomedical applications

Hydrogels are an advanced class of biomaterials with similar properties to living tissues. Several polymers have been investigated for the preparation of hydrogels that closely mimic the structural and functional properties of the extracellular matrix. Proteins with easily modifiable functional groups, specific biochemical effects, and sensitivity to external stimuli are promising candidates for the preparation of hydrogels for biomedical applications. Among them, natural milk proteins, due to their high yield, high-quality control, low cost, and certain biological properties, have become a major focus of research. However, there is a lack of comprehensive reviews focusing specifically on milk protein-based hydrogels. Here, we synthesise the developments in milk protein-based hydrogels, focusing primarily on hydrogels derived from milk proteins. We described the methods used to construct milk protein-based hydrogels and summarised advances in representative applications of milk protein-based hydrogels, such as controlled delivery and regenerative medicine, as well as related preclinical animal experiments and an exploratory clinical pilot study. Finally, we discuss the prospects of milk protein-based hydrogels in biomedical applications. We anticipate that this review will serve as a theoretical basis for the biomedical use of milk proteins and provide a reference for their continued development.