Development of functionally graded constructs via 3D microfluidic bioprinting for the regeneration of skeletal defects

Skeletal tissue engineering aims to prevail limitations of traditional treatments for bone defects by developing biomaterials that mimic the complex hierarchical architecture of natural bone. However, current biofabrication techniques face challenges in achieving both structural precision and biological compatibility. A major limitation is the lack of scalable methods to produce functionally graded materials (FGM) that support cell proliferation and differentiation while maintaining mechanical stability. This thesis proposes the development of a 3D microfluidic bioprinting platform using oil-in-water (O/W) and water-in-water emulsions (W/W) to fabricate porous scaffolds with controlled gradient structures. Crucially, integrating low-intensity pulsed ultrasound (LIPUS) stimulation and microbubbles (MBs) into the 3D bioprinting process for the first time, a functional response for cell growth and enhanced the osteogenic differentiation of skeletal stem cells (SSCs) was elicited. The results demonstrate that the 3D bioprinted constructs can actively promote effective bone tissue regeneration, addressing key limitations of current regenerative strategies, aforementioned. This thesis provides a novel, scalable solution for the creation of biocompatible and functional skeletal tissue constructs, with significant implications for clinical applications in bone repair.