Overcoming ice: cutting-edge materials and advanced strategies for effective cryopreservation of biosample

Cryopreservation techniques have been widely used, especially in biomedical applications and preservation of germplasm resources. Ideally, biological materials would maintain functional integrity as well as a normal structure and can be recovered when needed. However, this tool does not work all the time. Ice formation and growth are the key challenges. The other major reason is that the cryoprotective agents (CPAs) currently used do not meet these needs and are always accompanied by their cytotoxicity. A comprehensive and synergistic approach that focuses on the overall frozen biological system is crucial for the evolution of cryopreservation methods. In this review, we first summarize the fundamental damage mechanisms during cryopreservation, as well as common cryoprotectants and their limitations. Next, we discuss materials that interact with ice to improve cryopreservation outcomes. We evaluated natural and synthetic materials, including sugars and polymers, AFPs and mimics, ice nucleators, and hydrogels. In addition, biochemical regulation, which enhances the tolerance of biosamples to cryopreservation-induced stresses, was also mentioned. Nanotechnology, cell encapsulation, cryomesh, and isochoric freezing, such scalable approaches, are further discussed for cryopreservation. Finally, future research directions in this field for efficient cryopreservation are proposed. We emphasized the need for multidisciplinary progress to address these challenges. The combination of cryobiology mechanisms with technologies, such as synthetic biology, nanotechnology, microfluidics, and 3D bioprinting, is highlighted.