Sperm Micromotors for Cargo Delivery through Flowing Blood

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Reproductive Biology

Background:

• Synthetic micromotors face limitations in biological fluids due to insufficient thrust force.
• The circulatory system's high flow and complex composition impede micromotor functionality.
• Overcoming these challenges is crucial for in vivo applications like targeted drug delivery.

Purpose of the Study:

• To develop a hybrid sperm micromotor capable of navigating and functioning within the circulatory system.
• To enable active propulsion against blood flow for micromanipulation and cargo delivery.
• To investigate the potential of these micromotors as anticoagulant agents.

Main Methods:

• Development of a biohybrid system combining natural sperm with synthetic microstructures.
• Utilizing sperm flagella for propulsion and synthetic components for magnetic guidance and cargo loading.
• Magnetization of single sperm micromotors to enable assembly into train-like carriers.

Main Results:

• The hybrid sperm micromotors demonstrated active swimming against both continuous and pulsatile blood flow.
• The system successfully performed heparin cargo delivery, a key anticoagulant.
• Magnetized micromotors assembled into larger structures for enhanced cargo transport capacity.

Conclusions:

• Hybrid sperm micromotors offer a viable solution for untethered micromanipulation in the bloodstream.
• This biohybrid approach overcomes previous limitations of synthetic micromotors in complex biological environments.
• These micromotors show promise as novel anticoagulant agents for treating circulatory diseases.