Polymeric Tube-Shaped Devices with Controlled Geometry for Programmed Drug Delivery

Abstract

We developed a modular tube-shaped device as a proof of principle to enable programmed release of encapsulated molecules for controlled drug delivery. Each drug-delivery tube module was prepared by assembling two separate silicone tubes in series, one filled with a model compound (sodium fluorescein) and the other with a diffusional barrier material, polyethylene oxide (PEO). We varied the length of the PEO-filled tubes to control release from the drug-delivery tube devices. The onset times and periods of drug release increased with the length of the PEO tube in the drug-delivery tube device. To program drug release, therefore, we prepared devices with combinations of drug-delivery tube modules with PEO-filled tubes of different lengths. The combination of drug-delivery tubes with PEO-filled tubes each with very different lengths achieved pulsatile drug release, while a continuous drug release was realized by using a collection of PEO-filled tubes with small differences in length. We conclude that the modular combination of drug-delivery tubes, each composed of a diffusion-barrier tube of different length, demonstrates potential applications in programmed drug delivery.