Enhanced Osteogenic Differentiation via Collagen and BMP-2 Mimetic Peptide Conjugation to β-TCP Scaffolds Using a Cold Atmospheric Plasma-Assisted Strategy.

Abstract

Bone defects arising from trauma, disease, or surgical intervention represent significant challenges. Developing effective bone tissue engineering strategies to address these issues and promote repair is crucial. β-Tricalcium phosphate (β-TCP) has emerged as a promising synthetic graft due to its porous, degradable structure and excellent biocompatibility. However, the lack of biological cues in β-TCP limits its functionality, requiring different surface modification strategies. Bone morphogenetic protein-2 mimetic peptide (BMP; NSVNSKIPKACCVPTELSAI) and collagen mimetic peptide (CMP; GTPGPQGIAGQRGVV) have a known significant therapeutic potential due to their ability to enhance cell attachment and osteogenic differentiation. Herein, a peptide functionalization strategy for β-TCP scaffolds was introduced. Briefly, β-TCP was treated with cold atmospheric plasma (CAP) to create functional hydroxyl groups on the surface of the β-TCP. Subsequently, peptides were conjugated by using a three-step method: (1) silanization with APTES, (2) EDC activation, and (3) peptide conjugation. The successful surface modification with CAP and peptide conjugation was confirmed via XRD, FTIR, and Raman analysis. Furthermore, the effects of BMP and CMP peptides on osteogenic differentiation after CAP treatment were investigated in human mesenchymal stem cells (hMSCs). Both β-TCP/BMP and β-TCP/CMP scaffolds demonstrated excellent biocompatibility with hMSCs, enhancing cell proliferation and promoting osteogenic differentiation. Remarkably, β-TCP/CMP showed better results in terms of proliferation and differentiation compared with β-TCP/BMP. These findings highlight the clinical potential of peptide-functionalized β-TCP scaffolds for bone tissue engineering while also providing a promising methodology for β-TCP functionalization.