Press Releases

Safe Bioink for Artificial Organ Printing Developed

17 April 2023 -- Seoul, South Korea -- Dr Song Soo-chang's research team at the Center for Biomaterials, Korea Institute of Science and Technology (KIST, President Yoon Seok-jin), revealed the first development of poly(organophosphazene) hydrogel-based, temperature-sensitive bioink that stably maintained its physical structure only by temperature control without photocuring, induced tissue regeneration and then biodegraded in the body after a certain period of time.

The development of biomaterials for artificial organs and tissues is active due to an increase in accidental injuries and chronic diseases, along with the entry into a super-aged society. 3D bioprinting technology, which uses cells and biomaterials to create three-dimensional artificial tissue structures, has recently gained popularity. However, commonly used hydrogel-based bioinks can cause cytotoxicity due to the chemical crosslinking agent and ultraviolet light that connect the molecular structure of photocuring 3D-printed bioink.

Current hydrogel-based bioinks must go through a photocuring process to enhance the mechanical properties of the 3D scaffold after printing, with a high risk of adverse effects in the human body. In addition, there have been possibility of side effects by transplanting externally cultured cells within bioink to increase the tissue regeneration effect. Accordingly, the research team developed a new bioink material using a temperature-sensitive poly(organophosphazene) hydrogel, which existed in a liquid form at low temperatures and changed to a hard gel at body temperature. This enabled the regeneration of tissues only by temperature control without chemical crosslinking agents or UV irradiation and the manufacture of a three-dimensional scaffold with a physically stable structure, minimising the possibility of immune adverse effects in the human body.

The developed bioink also had a molecular structure that could interact with growth factors, which are proteins that help in tissue regeneration to preserve growth factors that regulated cell growth, differentiation and immune responses for a long period of time. The research team was able to maximise the effect of tissue regeneration by creating an environment in which cell differentiation could be autonomously regulated within the 3D scaffold printed with bioink.

The research team fabricated the 3D scaffold by printing it with a 3D bioprinter using bioink containing transforming growth factor beta 1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2), which were required for cell infiltration and bone regeneration, and conducted an experiment by implanting it into a damaged bone in a rat. As a result, cells from the surrounding tissue were migrated into the scaffold, and the defected bone was regenerated to a normal tissue level, and the implanted 3D scaffold slowly biodegraded in the body over 42 days.

Dr Song Soo-Chang of KIST said, "The research team has transferred technology for the thermo-sensitive polyphosphazene hydrogel to NexGel Biotech Co., Ltd. in June 2022, and the development of products such as bone graft materials and cosmetic fillers is underway. As the bioink developed this time has different physical properties, follow-up research to apply it to the regeneration of other tissues besides bone tissue is being conducted, and we expect to finally be able to commercialise bioink tailored to each tissue and organ."

About KIST
The Korea Institute of Science and Technology strives to solve national and social challenges and secure growth engines through leading and innovative research.

KIST was established in 1966 as the first government-funded research institute to establish a national development strategy based on science and technology and disseminate various industrial technologies to develop major industries. KIST, which played a role in establishing a national science and technology innovation system by creating 16 specialised research institutes, is now raising Korean science and technology status through world-leading innovative research and development.

In 2021, after half a century of establishment, KIST takes on a new challenge to become a global research institute that the people can believe, trust and be proud of. We take the lead in responding to dementia, particulate matter and infectious diseases that must be solved to improve the quality of life of the people while focusing on research that we must do as a national research institute. KIST pursues world-class excellence in research.

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