Freeze-Drying Process for the Fabrication of Collagen-Based Sponges as Medical Devices in Biomedical Engineering

Abstract

This paper presents a systematic review of a key sector of the much promising and rapidly evolving field of biomedical engineering, specifically on the fabrication of three-dimensional open, porous collagen-based medical devices, using the prominent freeze-drying process. Collagen and its derivatives are the most popular biopolymers in this field, as they constitute the main components of the extracellular matrix, and therefore exhibit desirable properties, such as biocompatibility and biodegradability, for in vivo applications. For this reason, freeze-dried collagen-based sponges with a wide variety of attributes can be produced and have already led to a wide range of successful commercial medical devices, chiefly for dental, orthopedic, hemostatic, and neuronal applications. However, collagen sponges display some vulnerabilities in other key properties, such as low mechanical strength and poor control of their internal architecture, and therefore many studies focus on the settlement of these defects, either by tampering with the steps of the freeze-drying process or by combining collagen with other additives. Furthermore, freeze drying is still considered a high-cost and time-consuming process that is often used in a non-optimized manner. By applying an interdisciplinary approach and combining advances in other technological fields, such as in statistical analysis, implementing the Design of Experiments, and Artificial Intelligence, the opportunity arises to further evolve this process in a sustainable and strategic manner, and optimize the resulting products as well as create new opportunities in this field.

Bioactive gelatin-sheets as novel biopapers to support prevascularization organized by laser-assisted bioprinting for bone tissue engineering

“…Highly porous hydrogels can be produced using various methods, such as freeze-drying. The variation in the parameters of the freeze-drying procedure made it possible to control the microarchitecture of the porous biopaper and optimize the pore size for the intended application [33]. In accordance with many authors, our results demonstrated the major impact of freezing temperature and cooling rate on the porous structure of the scaffold, which is conditioned by the nucleation of ice [34,35].…”

Artificial Intelligence (AI) Based Analysis ofIn VivoPolymers and Collagen Scaffolds Inducing Vascularization

“…Collagen-based scaffolds were also associated with inflammation, but to a lesser degree (13)(14)(15). Another contentious matter regarding the utilization of biomaterials is their capacity to stimulate angiogenesis and achieve vascularization (16)(17)(18).…”

Donkey Gelatin and Keratin Nanofibers Loaded with Antioxidant Agents for Wound Healing Dressings

“…Nanofibers for innovative medical dressings manufactured using the electrospinning technique must fulfill several requirements: to absorb excess exudates, provide and maintain a moist environment or an adequate water vapor transmission rate, possess smaller pores compared to fibers produced using traditional methods, exhibit good cellular adhesion to support cell proliferation, and enhance the healing process. Nonetheless, there is evidence that the use of inflammable liquids with high shear strength and voltage can potentially generate permanent denaturation of the collagen fibrous structure [ 28 ]. Our previous publications reported the fabrication of nanofibrous wound dressings by the electrospinning process of different protein extracts, such as collagen derived from cattle hides [ 29 , 30 ], rabbit skins [ 31 , 32 ], fish scales [ 33 , 34 ], donkey hides [ 34 ], or keratin extracted from sheep wool [ 35 ], loaded with various non-active antimicrobial agents and having advanced regenerative properties for acute and chronic wound healing.…”