Effect of barium titanate nanoparticles on pore architecture and early-stage chondrocyte response in breath figure–derived PLDLA scaffolds

A suitable microenvironment is essential for chondrocytes to maintain their phenotype and extracellular matrix (ECM) production during long-term in vitro culture. Pore structure, interconnectivity, and the ability to provide natural cellular cues are important properties in the scaffolds. Additionally, piezoelectric materials such as barium titanate can provide electromechanical stimulation to influence cellular behaviour. This study investigated the effect of the barium titanate nanoparticles (BTNP) on pore formation in poly-L/ D -lactide copolymer (PLDLA) scaffolds fabricated using the breath figure method. The final nanoparticle content, pore structure, and interconnectivity were characterised. Human articular chondrocytes were cultured on the scaffolds for two weeks to evaluate cytotoxicity, cell proliferation, cell morphology, and ECM production. The micropatterned porous structure was maintained across all PLDLA/BTNP scaffolds (BTNP content: 0, 10, 20, 30, and 40 wt%). X-ray microtomography (XRM) was able provided insight into pore structure and interconnectivity of the scaffolds. Pore diameter increased in the PLDLA/BTNP scaffold to approximately 20 µm, while in the PLDLA scaffolds, it was 2 µm. All PLDLA/BTNP scaffolds were non-cytotoxic, and cells were more spherical in the PLDLA/BTNP scaffolds, but there was no difference in ECM production. Overall, the amount of BTNPs influenced the scaffold structure. These early-stage findings demonstrated that scaffolds were non-cytotoxic and exhibited a porous architecture conducive to cell growth and maintenance. These findings highlight the potential of the developed PLDLA/BTNP scaffolds as three-dimensional platforms for long-term in vitro studies, enabling the investigation of cellular behaviour and cell–material interactions under physiologically relevant conditions.