A Soft Capsule for Magnetically Driven Drug Delivery Based on a Hard-Magnetic Elastomer Foam

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Soft Robotics

Background:

• Porous soft biomaterials are used for stimuli-responsive drug release.
• Magnetic-responsive materials offer real-time control but lack predictable release profiles.
• Accurate dosage regulation remains a challenge for current magnetic drug delivery systems.

Purpose of the Study:

• To develop a magnetically controlled on-demand drug delivery system.
• To create a soft capsule with predictable and repeatable drug release profiles.
• To demonstrate the potential of this system as a soft robot for in-body drug delivery.

Main Methods:

• Fabrication of a soft capsule using flexible hard-magnetic elastomer foam (HEF) with interconnected pores.
• Utilizing precompressed magnetization to achieve significant compressive deformation of the HEF.
• Magnetic field application to control the deformation and thus the drug release rate.
• Testing the capsule's drug release predictability and dosage regulation accuracy.
• Evaluating the capsule's performance as a magnetically driven soft robot in a human stomach model.

Main Results:

• The HEF capsule demonstrated an adjustable drug release rate from 0.02 to 1.7 mL/min.
• Drug release profiles were accurately predicted with 85% accuracy in dosage regulation.
• Achieved over 90% maximum cumulative drug release.
• Successfully performed magnetically driven drug delivery in a human stomach model.
• The HEF material exhibits a low elastic modulus (10 kPa) and 81% interconnected pores.

Conclusions:

• The developed HEF capsule enables precise, on-demand drug delivery with predictable release kinetics.
• This technology offers a significant advancement in regulating drug dosage for therapeutic applications.
• The HEF capsule shows promise as a versatile soft robot for various biomedical applications within the human body.