3D-printed PETG/BC scaffolds for bone tissue repair

Abstract

Bone tissue supports the body, enables movement, protects organs, produces blood cells, and stores minerals. In regenerative medicine, bone’s natural healing ability drives the need for engineered solutions to treat fractures, defects, and support implants. This study explores the development of polyethylene terephthalate glycol (PETG) and PETG/bacterial cellulose (BC) composite scaffolds with varying BC contents (10, 15, and 20 wt%) for bone tissue engineering (TE). Scanning electron microscopy and atomic force microscopy revealed porous structures with increasing surface roughness as BC content increased. Water contact angle analysis revealed enhanced hydrophilicity in PETG/BC composites, particularly at higher BC levels. Fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry confirmed successful BC integration and interactions with PETG, along with increased crystallinity. Mechanical testing indicated that compressive strength improved with higher BC content, with 20 wt% BC achieving optimal performance. Biological tests using human adipose-derived stem cells displayed enhanced proliferation, differentiation, and mineralization on PETG/BC scaffolds. Among the tested BC scaffolds, the 20 wt% BC scaffold demonstrated the most favorable physical, mechanical, and biological properties. Overall, PETG/BC scaffolds, especially those with 20 wt% BC, display strong potential for future bone TE applications.

Keywords

Additive manufacturing / Bacterial cellulose / Biomaterial / Polyethylene terephthalate glycol / Stem cells / Tissue engineering

Funding

This project was partially supported by the University of Manchester and UKRI through EPSRC (grant number: EP/ V011766/1). Additionally, this work was also supported by the Henry Royce Institute for Advanced Materials (grant number: EP/S019367/1).

Conflict of Interest

Paulo J.D.S. Bartolo is an Editorial Board Member of the journal, but was not in any way involved in the editorial and peer-review process conducted for this paper, directly or indirectly. Other authors declare they have no competing interests.

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