3D Printed Fractal-like Structures with High Percentage of Drug for Zero-Order Colonic Release

Abstract

Colonic drug delivery of drugs is an area of great interest due to the need to treat high prevalence colonic local diseases as well as systemic conditions that may benefit from the advantages associated to this route of drug administration. In the last decade, the use of 3D printing technologies has expanded, offering the possibility of preparing personalized medicines in small batches directly at the point of care. The aim of this work is to design a high drug loaded 3D printed system prepared by a combination of Fused Deposition Modelling (FDM) and Injection Volume Filling (IVF) techniques intended for zero-order colonic drug release. For this purpose, different batches of binary and ternary filaments based on the thermoplastic polyurethane Tecoflex EG-72D (TPU), theophylline anhydrous (AT) as model drug, and magnesium stearate as lubricant have been developed and characterized. Filaments with the highest drug load and the best rheological properties were selected for the manufacture of a printed fractal-like structure based on multiple toroids. This design was proposed to provide high surface area, leading to increased drug release and water uptake in the colonic region. This structure was 3D printed by FDM and then coated in a unique step by IVF technology using the enteric polymer DrugCoat S 12.5. This way, an additional coating process is avoided, reducing costs and production time. Studies of drug release confirmed the ability of the structures to provide a five-hour period of constant drug delivery in the colonic region.

3D Printing Direct Powder Extrusion in the Production of Drug Delivery Systems: State of the Art and Future Perspectives

“…In these cases, the technique is no longer a single-step process, losing one of the main advantages of the DPE. Nevertheless, the homogeneity of the filament diameter, which is a limiting factor in FDM [ 43 , 56 , 57 , 58 ], does not affect it in these circumstances.…”

Controlled Architectures in Supported Photocatalysis: Exploring the Potential of Cold Plasma Discharge, Additive Manufacturing, and Fractal Geometry to Form Hierarchically Immobilized Ni-MOF/BiOI/AgVO3

“…In recent years, AM technologies combined in surprising ways with fractal geometry to offer unique innovations in a wide range of domains, such as bone prosthetics, drug delivery, stretchable electronics, fluid rheology, chemical engineering, mechanics of soft tissues, and so on. − The utilization of principles based on fractal theory opens the way for completely new routes to consider and produce complex materials. Using an innovative approach of supported photocatalysis, we combine AM and fractal design to generate substrates with a relatively high surface area, available for CPD-driven immobilization of photocatalysts. ,, …”

Development of 3D-Printed Bicompartmental Devices by Dual-Nozzle Fused Deposition Modeling (FDM) for Colon-Specific Drug Delivery

“…During this process, formulations containing the matrix-forming polymer, drugs, and, if necessary, other excipients are homogeneously mixed, heated, and extruded through a die into filaments with a suitable diameter. The coupling of HME and FDM technologies expands the number of pharmaceutical-grade polymers processable by 3D printing, and hence, possibilities for the design of drug delivery systems [ 1 , 4 , 12 , 13 , 14 ].…”