Characterization of mechanical properties and microstructure of hydrogel scaffolds by X‑ray propagation-based imaging

Characterization of the mechanical properties and internal microstructure of scaffold, once implanted, is imperative in tissue engineering and medicine regeneration. Notably, this has been challenging to date as various conventional characterization methods by, for example, mechanical testing (for mechanical properties) and microscope (for internal microstructure) are destructive as they require removing scaffolds from the implantation site and processing samples for characterization. Synchrotron radiation X‑ray propagation-based computed tomography (SR-PBI-CT) is feasible and promising for nondestructive monitoring of hydrogel scaffolds. With the high brightness and high coherence of synchrotron radiation source, SR-PBI imaging is able to visualize and distinguish low-density soft tissues and hydrogels with high spatial resolution and scan speed, while the feature of large imaging depth with X-ray CT ensures the reconstruction of the three-dimensional (3D) scaffold. As inspired, this study aimed to perform a study on the characterization of mechanical properties and microstructure of hydrogel scaffolds by the SR-PBI-CT imaging.