Exploring the potential of supercritical carbon dioxide for eugenol impregnation in 3D printed polylactic acid structures

Abstract

Biocompatible implants are essential for improving human health and longevity. Incorporating bioactive compounds, such as eugenol, into implant materials can improve biocompatibility and therapeutic efficacy. This study examines the effects of supercritical eugenol impregnation on the physical properties of 3D-printed polylactic acid samples produced by Fused Deposition Modeling. Impregnation was performed using a lab-scale high-pressure system, evaluating the impact of impregnation time on eugenol loading, distribution, and morphology. Fourier Transform Infrared spectroscopy confirmed homogeneous eugenol distribution with impregnation times exceeding 1 h, achieving loadings up to 12 wt%. Eugenol was released slowly over extended periods in a phosphate-buffered solution. Impregnated samples displayed more amorphous thermal behavior, with decreased Tg due to the plasticizing effect of the CO₂-eugenol mixture. Mechanical properties were slightly altered, with reduced stiffness and increased toughness. Microscopic deformations induced by impregnation could potentially enhance cellular adhesion, improving biocompatible material performance.