2022, Vol. 26 ›› Issue (18): 2914-2921

Reasonable choice and application of bio-ink sterilization technology for 3D bioprinting

Yuan Long1, Li Sen1, Bian Jichao1, Li Wanxiang1, Wang Guodong2   

Abstract: BACKGROUND: The application of 3D bioprinting is becoming more and more extensive, and the related bio-ink sterilization is very important. However, the sterilization problem of bio-ink used for clinical purposes has not been resolved.   
OBJECTIVE: To summarize the current research progress of bio-ink sterilization technology for 3D bioprinting.
METHODS:   Retrieve relevant documents were retrieved on CNKI, Wanfang Data Platform, PubMed, and Web of Science databases, with the search terms of “3D bioprinting, tissue engineering, additive manufacturing, bio-ink, biomaterials, sterilization, disinfect, aseptic”. Finally, 77 relevant articles were included for review.   
RESULTS AND CONCLUSION: Different sterilization methods have bad effects on bio-ink for 3D bioprinting while sterilizing bio-ink. (1) Some sterilization methods can damage the microstructure in the biological ink. For example, radiation sterilization and ultraviolet light produced free radicals can affect biological fluid mechanics and plasticity of ink. Acetic acid peroxide dissolved biological ink ingredients due to its strong oxidizing. The mechanical performance requirements of high material should reduce to use this kind of sterilization method. (2) Some sterilization methods can damage the activity of the biological ink containing biological macromolecules, such as autoclaving of high-energy water vapor, radiation sterilization, and ultraviolet light produced free radicals can lead to loss of biological macromolecules such as protein and enzyme activity. Therefore, biological ink that requires biological macromolecules to be active should reduce to use this kind of sterilization method. (3) Some sterilization methods will remain some toxic substances: for example, ethylene oxide sterilization residues have carcinogenicity and affect the survival of seed cells, so the biological ink that needs to be loaded with seeds should reduce the use of this sterilization method. (4) Some sterilization methods for ink cannot complete a thorough sterilization. For example, ethanol and antibiotic during sterilization limited by its own nature cannot always be completed on biological sterilization of ink, so it often needs to be combined with other methods, such as the combination of different kinds of antimicrobial and the combination of peracetic acid with ethanol, which can not only realize the complementary advantages bus also avoid additional adverse effects. (5) Therefore, the material characteristics, the purpose of material application and the principle of sterilization should be considered when selecting the optimal bio-ink sterilization method for 3D bioprinting.
Key words: 3D bioprinting, tissue engineering, additive manufacturing, bio-ink, biomaterials, sterilization, disinfect, aseptic