Exploring the potential of Supercritical Carbon Dioxide for Eugenol impregnation in 3D printed Polylactic Acid Structures

JANET CHINELLATO; MARCELO R. ROMERO; FACUNDO MATTEA

Los cocos

Conferencia; VI Iberoamerican Conference on Supercritical Fluids; 2023

The development of antimicrobial polymeric systems holds significant promise in the battle against the spread of diseases, thereby enhancing health conditions in the field of medical science and the food industry. In addition, the creation of degradable materials plays a crucial role in addressing the global plastic pollution. One of the synthetic polymers showing great potential in replacing conventional plastics is polylactic acid (PLA). PLA, a versatile polyester, is recognized for its biocompatibility, biodegradability, and bioresorbability, finding applications in various fields such as medical science, engineering devices, and food packaging (Singhvi et al., 2019; Malek et al., 2021). Notably, PLA possesses favorable mechanical properties for 3D printing, making it a viable alternative for constructing prostheses (Wu et al., 2019). Furthermore, the ability of PLA to be reabsorbed by the body's biochemical systems enhances its value as a biopolymer for tissue engineering applications. This characteristic eliminates the need for additional surgeries in patients with implants or cell regeneration devices, presenting promising prospects in the field (Singhvi et al., 2019; Malek et al., 2021). The functionalization of PLA by incorporating antimicrobial active compounds is an area that is experiencing continuous growth and exploration, especially with substances from natural sources. Among the promising antimicrobial compounds, eugenol stands out as a noteworthy candidate. Eugenol is a key volatile component found in clove essential oil, renowned for its antimicrobial properties. However, its benefits extend beyond just antimicrobial activity, as it also exhibits anti-inflammatory, analgesic, antioxidant, and even anticancer properties (Kamatou et al., 2012). Currently, there is limited research available on systems that utilize both PLA and eugenol (Li et al., 2021; Huang et al., 2022). To the best of our knowledge, the use of supercritical carbon dioxide (ScCO2) assisted impregnation for incorporating eugenol into PLA has not been reported in the literature. Supercritical carbon dioxide (ScCO2) has been recognized as a clean alternative to conventional impregnation techniques. Its inert nature ensures that any residues left on the material are harmless, making it an environmentally friendly option Additionally, ScCO2 is cost-effective, non-flammable, and easy to recycle or dispose of (Mosquera et al., 2019). Taking all these into account, the aim of the present work was to study the ScCO2 impregnation of eugenol into 3D structures of commercial PLA. The 3D structures were printed using a Fused deposition modeling (FDM). Impregnation runs were carried out in a lab-scale high pressure system, evaluating the effect of different operation variables on impregnation loading, morphology of the printed structures, and active compound distributions within printed structures. The analysis of the 3D structure, before and after the ScCO2 impregnation, was carried out by reflectance confocal optical microscopy technique and the distribution of eugenol was compared by means FTIR measurements.