Active Regulation of On‐Demand Drug Delivery by Magnetically Triggerable Microspouters

Abstract

Triggerable devices capable of on‐demand, controlled release of therapeutics are attractive options for the treatment of local diseases because of their potential to enhance therapeutic effectiveness with reduced systemic toxicity. Here, the design and fabrication of a miniaturized device, termed a microspouter, is described. This device is shown to provide active and precise control of localized delivery of drugs on demand. The microspouter is composed of a magnetic sponge to provide the force for drug release through magnetic field‐induced reversible deformation, a reservoir for the sponge installation and drug loading, and a soft membrane for sealing the device. Following application of a magnetic field to the microspouter, the shrinking of the sponge may trigger a spouting of drug through a membrane's microaperture. The efficiency of the device in controlling the dose and time course of drug release under different external magnetic fields has been demonstrated using methylene blue and docetaxel as model drugs. Additionally, the microspouter is found to have low background drug leakage that allows for tunable drug release in an ex vivo implantation experiment. All the results confirm the microspouter as a potential device for safe, long‐time, and controlled drug release in local disease treatment.

Microfabricated Drug Delivery Devices: Design, Fabrication, and Applications

“…Semipermanent PPs are made from silicone, HEMA, PCL, or Teflon and intended for six-month use. 2017 MEMS devices with pump-like release mechanisms using magnetic films, magnetic blocks, magnetic sponges, or magnetic actuated plungers [103,109,257] Devices applied to specific sites Temporary PPs that are made from animal collagen last for 4-10 d and dissolve.…”

“…[96,254] When the membrane was heated by the embedded magnetic nanoparticles in the presence of an oscillating magnetic field, the nanogels shrank, increasing the permeability of the membrane for drug release from the reservoir. [256,257] A powerless drug delivery device termed a microspouter was prepared to provide active and precise control of localized drug delivery Adv. The hydrogel was loaded with drugs and placed in a capsule.…”

“…The hydrogel was loaded with drugs and placed in a capsule. [257] Copyright 2017, Wiley-VCH. [255] In another device, Fe 3 O 4 particles are used to block/open the pores of a membrane covering on the reservoir by controlling their movement inside the drug reservoir, achieving a reversible switching of drug flux and finally pulsatile release ( Figure 9C(b)).…”

“…When the membrane deflected under external magnetic fields, the drug was released through a microaperture at the center of the membrane. [257] The microspouter consisted of a magnetic sponge to provide the force for drug release based on magnetic field-induced reversible deformation, a reservoir for the sponge installation and drug loading, and a soft membrane for sealing the device. In their recent reports, magnetic PDMS sponges made of porous PDMS scaffolds with embedded magnetic microparticles were fabricated and used for remotely triggered drug release.…”

“…[147] Adv. Funct MEMS devices with pump-like release mechanisms using magnetic films, magnetic blocks, magnetic sponges, or magnetic actuated plungers [103,109,257] Devices applied to specific sites…”