3D printed bioactive scaffold integrating polyallylamine hydrochloride-dextran matrix with diopside nanoparticles and deferoxamine for dual osteogenic-angiogenic stimulation

Abstract

Critical-sized bone defects resulting from trauma or pathological conditions remain a major clinical challenge. Tissue engineering offers promising strategies for bone repair, with scaffold design focusing on optimal morphology, mechanical integrity, and bioactivity. Recent advances in 3D printing have transformed scaffold fabrication, enabling the production of customized and patient-specific constructs tailored for biomedical applications. In this study, a 3D printed scaffold composed of dextran (Dx) and polyallylamine hydrochloride (PAH) was developed and functionalized with diopside (Dp) nanoparticles and deferoxamine (Df) to enhance bone tissue regeneration. The resulting PAH.Dx/Dp.Df scaffold (S4) demonstrated superior compressive strength (3.17 MPa vs. 2.23 MPa) and elastic modulus (1.59 MPa vs. 1.17 MPa) compared to the unmodified PAH.Dx scaffold (S1). A sustained release profile was observed for Df, with 94.0 released within 14 days. Additionally, ion release profiles (Ca2+, Si4+, Mg2+), biodegradability, and bioactivity were assessed over a 28-day period. The incorporation of both Dp nanoparticles and Df significantly enhanced the scaffold's osteogenic and angiogenic potential. Collectively, these findings suggest that the PAH.Dx/Dp.Df scaffold (S4) is a biocompatible and customizable platform capable of promoting vasculo-osteogenic responses, making it a promising candidate for bone tissue engineering applications.