Enhancing 3D printed PET physicochemical properties to prevent bacterial adhesion: Phenolic compound-based approach

Polyethylene terephthalate (PET) has emerged as a versatile and widely used polymeric material in the healthcare sector, particularly for medical device manufacturing, owing to its exceptional properties such as biocompatibility, high uniformity, and mechanical strength. However, the susceptibility of PET to bacterial adhesion remains a critical challenge in medical applications, potentially leading to serious complications for patients. In this study, we assessed, using the contact angle and scanning electron microscopy (SEM) techniques, the effectiveness of various phenolic compounds, including gallic acid (GA), tannic acid (TA), caffeic acid (CA) and epigallocatechin gallate (EGCG), in preventing the adhesion of Staphylococcus aureus and Pseudomonas aeruginosa to 3D printed PET surfaces. The results revealed that PET, initially hydrophobic (θ_w = 75.7 ± 0.56° and ΔGiwi = −52.17 mJ/m²), became hydrophilic after treatment with TA, GA and CA, enhancing its physicochemical properties. Additionally, GA demonstrated remarkable anti-adhesive efficacy against S.aureus with inhibition percentage of 97.4 %, whereas TA exhibited a high inhibition rate against P.aeruginosa (98.5 %). In contrast, PET remained qualitatively hydrophobic after treatment with EGCG, which showed limited anti-adhesive efficacy with a percentage of coverage by S.aureus and P.aeruginosa of 70.15 and 92.7 %, respectively. These findings contribute to the development of sustainable anti-adhesive surfaces for medical devices.