A process-driven approach for manufacturing personalized intravaginal rings using droplet deposition modeling

Droplet Deposition Modeling (DDM) is an additive manufacturing technology with potential applications in personalized drug delivery systems, enabling the production of drug products tailored to individual patient characteristics. This study explores the application of DDM in manufacturing customized intravaginal rings (IVRs) using β-estradiol as a model drug, focusing on how three key printing parameters-infill density (ID), droplet aspect ratio (DAR), and discharge rate (DR)-affect the performance characteristics of 3D-printed IVRs. These characteristics include surface morphology, porosity, weight, mechanical and viscoelastic properties, as well as in vitro drug release. The 3D-printed IVRs exhibited high dimensional accuracy and uniformity within batches. The results demonstrated that increasing ID from 70% to 90% and DR from 56% to 62% led to higher weight, Shore M hardness, compression strength, Young's modulus, storage modulus, and loss modulus, while decreasing porosity. On the other hand, increasing DAR from 1.1 to 1.3 produced opposing trends. Drug release was predominantly influenced by variations in ID and DAR, with higher ID values associated with slower drug release rates. These findings provide insight into the mechanisms governing the DDM process in pharmaceutical applications and highlight the importance of printing parameters for optimizing the quality and functionality of personalized IVRs. This work demonstrated the potential of additive manufacturing in enabling personalized medicine and distributed manufacturing of drug delivery systems, contributing to the advancement of patient-specific healthcare solutions.