Going for a Spin: Simultaneously Pulling and Spinning Microrods Speeds Transport through Collagen Matrices

Area of Science:

• Biophysics
• Materials Science
• Biomedical Engineering

Background:

• Magnetic drug targeting faces challenges due to complex biological environments hindering particle motion.
• Standard magnetic force methods are often inefficient for long-range transport of microrods in tissues.

Purpose of the Study:

• To design and evaluate magnetic microrods capable of enhanced transport through viscoelastic biological environments.
• To investigate if simultaneous magnetic force and torque actuation can overcome transport limitations.

Main Methods:

• Fabrication of microrods with orthogonally magnetized segments.
• Modeling of magnetic force and torque on the microrods.
• In vitro characterization of microrod dynamics and transport through protein-dense matrices.

Main Results:

• Developed magnetic drilling microrods (MDMRs) actuated by simultaneous magnetic force and torque.
• Demonstrated enhanced motion of MDMRs through challenging protein-dense biopolymer matrices.
• Observed that combined pulling and rotating motion overcomes transport hindrances.

Conclusions:

• Simultaneous magnetic force and torque actuation enables microrods to overcome transport hindrances in complex biological media.
• MDMRs show potential for improved efficiency in magnetic drug targeting applications.
• This approach offers a novel strategy for navigating biological barriers with magnetically guided particles.