Bioresorbable poly(lactic acid) and organic quantum dot-based nanocomposites: luminescent scaffolds for enhanced osteogenesis and real-time monitoring

Abstract

Globally, millions require bone replacements with the help of scaffolds to enable bone tissue regeneration. However, scaffold manufacturing techniques do not allow precise control over scaffold geometry and provide diagnostics on scaffold-cell status. Towards addressing these challenges, we studied the use of optimized 3D printing of bioresorbable scaffolds with fluorescent carbon quantum dots (CDs). These can overcome the challenges with toxic and invasive dyes used in clinical settings as probes, while promoting cellular adhesion, proliferation, and osteogenic differentiation. We developed a biodegradable polymer nanocomposite based on PLA with CDs to produce smart biomaterials. As a luminescent, biocompatible material with low toxicity, CDs allowed us to fabricate functionalized biochemical structures that were shown to enhance cell proliferation and promote cell-to-cell communication. The composites were tested in vitro in a cellular microenvironment with optimized 3D-printed scaffolds to demonstrate enhancements in cellular proliferation by 32%, bone mineralization by 8% and osteogenic differentiation by 8% with concomitant negligible cytotoxic effect.