Reviewed by Lexie CornerFeb 4 2025
A research team from Seoul National University of Science and Technology, Republic of Korea, led by Professor Insup Noh, has developed a bioink using nanocellulose derived from Kombucha SCOBY (Symbiotic Culture of Bacteria and Yeast) as a scaffold material. The study was published in the International Journal of Biological Macromolecules.
Tissue engineering facilitates the regeneration of damaged tissues, including skin, cartilage, and organs, by growing human cells on scaffolds using 3D printing and bioink. The developed biomaterial is compatible with a portable "Biowork" biopen, also designed by the research team, offering an alternative to conventional scaffold materials.
The digital biopen allows for the precise application of bioink to irregular surfaces, such as cartilage defects and extensive skin wounds. This approach enables direct in vivo tissue repair, reducing the need for in vitro tissue engineering processes.
Our prefabricated nanocellulose hydrogel network from symbiotic culture of bacteria and yeast has the potential to be used as a platform bioink for in vivo tissue engineering by loading all types of biomolecules and drugs and direct bioprinting.
Insup Noh, Professor, Seoul National University of Science and Technology
Kombucha SCOBY, a symbiotic culture of yeast and bacteria, ferments green tea and produces biocompatible and biodegradable nanocellulose. However, the entangled structure of Kombucha SCOBY-derived nanocellulose requires modification for 3D bioprinting. Adjustments to its rheological (flow) and mechanical properties are necessary to improve extrusion and maintain structural integrity after printing.
To enhance bioprintability, researchers partially hydrolyzed nanocellulose using acetic acid, breaking glucose bonds and reducing network entanglement. However, this treatment weakened its structural strength due to a lack of property control. To reinforce the material, the team incorporated negatively charged kaolin and positively charged chitosan nanoparticles. These components interact electrostatically with cellulose to form a stable hydrogel suitable for 3D bioprinting.
The bioink was prepared by mixing all components, including live cells, directly within a biopen. The biopen, controlled by a computer, contained two counter-rotating screws that uniformly combined the ingredients, allowing direct application to damaged tissue via a needle.
When connected to a 3D bioprinter, the biopen produced high-resolution, multilayer, self-supporting structures, such as bifurcated tubes and pyramids over 1 cm in height. It was also used for direct in situ layer-by-layer printing to fill irregularly shaped defects. The researchers successfully applied the bioink to precisely fill 3D-printed femoral head and cranium molds with predefined defects.
The combination of bioink and a digital biopen provides a cost-effective method for treating large or irregularly shaped wounds, particularly in emergency and first-aid applications, without requiring an in vitro tissue regeneration process.
This technology allows for a quick and easy one-step process where the drug and hydrogel are mixed and immediately applied on-site to injured areas of different shapes.
Insup Noh, Professor, Seoul National University of Science and Technology
Journal Reference:
Bhattacharyya, A., et al. (2025) Simultaneous processing of both handheld biomixing and biowriting of kombucha cultured pre-crosslinked nanocellulose bioink for regeneration of irregular and multi-layered tissue defects. International Journal of Biological Macromolecules. doi.org/10.1016/j.ijbiomac.2024.136966