Ultrasound-mediated piezoelectricity enhancement in bioresorbable polymers

Area of Science:

• Biomaterials Science
• Polymer Science
• Medical Device Engineering

Background:

• Biodegradable piezoelectric materials are crucial for self-powered transient medical devices.
• Existing biodegradable polymers lack the high performance required for these applications.

Purpose of the Study:

• To enhance the piezoelectric properties of poly-L-lactide (PLLA) using a high-frequency ultrasound treatment.
• To develop a high-performance, biodegradable piezoelectric polymer for biomedical applications.

Main Methods:

• Utilized high-frequency ultrasound (1.2 MHz) to induce standing-wave crystallization and ferroelectric electret formation in PLLA.
• Characterized the piezoelectric coefficient (d33) of the ultrasound-treated PLLA (US-PLLA).
• Evaluated the biodegradability, biocompatibility, and in vivo degradation of US-PLLA.

Main Results:

• Ultrasound treatment significantly increased the piezoelectric coefficient (d33) of PLLA to 10.8 pC/N.
• US-PLLA demonstrated high performance comparable to non-degradable piezoelectric polymers like PVDF.
• US-PLLA exhibited safe in vivo degradation without organ toxicity and maintained biocompatibility.
• Demonstrated functional applications including real-time biosignal monitoring and enhanced cardiac recovery in a rat myocardial infarction model.

Conclusions:

• Ultrasound-mediated crystallization is an effective strategy for developing high-performance biodegradable piezoelectric polymers.
• US-PLLA is a promising material for transient biomedical systems requiring self-powered capabilities.
• This approach paves the way for advanced biodegradable electronics in medicine.