Enzyme-Powered Nanomotors with Controlled Size for Biomedical Applications

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Materials Science

Background:

• Microscale self-propelled motors face limitations for in vivo studies.
• Previous 400 nm nanomotors offered drug delivery and controlled motion.
• Nanoparticles (20-200 nm) show enhanced cellular barrier penetration and uptake.

Purpose of the Study:

• To fabricate ultrasmall stomatocyte nanomotors below 200 nm.
• To enable efficient shape transformation and cargo encapsulation in smaller motors.
• To evaluate their potential as biomedical carriers.

Main Methods:

• Fabrication of ultrasmall stomatocyte polymersomes (approx. 150 nm).
• Utilized polyethylene glycol (PEG) additive for shape control and encapsulation.
• Encapsulated catalase biocatalyst for propulsion via hydrogen peroxide (H2O2) conversion.

Main Results:

• Ultrasmall stomatocyte motors achieved propelled motion in 2 mM H2O2.
• Motor velocity correlated with oxygen (O2) production.
• Demonstrated enhanced vascular model penetration and HeLa cell uptake compared to larger motors.

Conclusions:

• Ultrasmall stomatocyte nanomotors (150 nm) are feasible biomedical carriers.
• PEG additive facilitates shape transformation and biologic encapsulation.
• These motors show superior performance in penetration and cellular uptake for targeted delivery.