Integration of finite element simulations with 3D printing technology for personalized Chitin/PLA microneedle-based drug delivery systems in thoracic keloid treatment.

The high prevalence of keloids in the thoracic (48.9 %) is closely associated with its unique anatomical morphology and mechanical environment. The irregular shape of keloids in this area significantly complicates treatment, particularly regarding drug delivery. Microneedle arrays (MNAs) have demonstrated remarkable advantages in the scar treatment due to their ability to deliver drugs evenly. However, existing MNAs often lack personalized design and present challenges during the treatment, such as unable to conform to the distinctive shapes of thoracic keloids, leading to uneven drug penetration. Consequently, we propose a preparation strategy for MNAs designed to meet the personalized treatment needs of thoracic keloids. In this study, personalized MNAs were constructed using 3D printing technology, incorporating chitin into polylactic acid (PLA) to enhance printing accuracy and drug-loading capacity. By integrating compressive properties of keloids with finite element analysis (FEA), we simulated the puncturing of keloids with a composite MNAs. The results indicated that the 0.2Chitin/PLA improves the accuracy and mechanical properties of the 3D-printed MNAs, and the drug-loading performance was improved by 6 times. Furthermore, FEA results revealed that Chitin/PLA MNAs can withstand the reaction forces encountered during the puncture process, thus achieving effective puncture depth. FEA combined with 3D printing and drug loading technology can effectively address the personalized needs and drug delivery in the treatment of thoracic keloids. This strategy not only improves the accuracy and effectiveness of the treatment, but also provides new research directions and technical support for the personalized treatment of keloids.