Programmable acoustofluidic engineering for creating gradient biomaterials.

Area of Science:

• Biomaterials Science
• Bioengineering
• Acoustofluidics

Background:

• Gradient biomaterials with spatially varying properties are essential for applications like tissue engineering and drug delivery.
• Existing fabrication methods lack precision, material compatibility, and reproducibility.

Purpose of the Study:

• To introduce a programmable system, Gradient Regulation via Acoustofluidic Dynamic Engineering (GRADE), for high-fidelity gradient biomaterial fabrication.
• To overcome limitations of current gradient material fabrication techniques.

Main Methods:

• Utilized focused interdigital transducers and pulsed surface acoustic wave actuation for tunable acoustic streaming.
• Employed an open microchannel design for nondestructive extraction of centimeter-scale gradients.
• Demonstrated composition-independent fluid manipulation for diverse biomaterials and cross-linking methods.

Main Results:

• Achieved tunable and directional acoustic streaming (0-22 mm/s) for precise gradient control.
• Fabricated centimeter-scale gradients non-destructively, enabling device reuse.
• Showcased GRADE's versatility with various biomaterials and cross-linking techniques.
• Validated platform usability by demonstrating stem cell stiffness-dependent mechanosensation on gradient substrates.

Conclusions:

• GRADE is a powerful and versatile platform for fabricating high-fidelity gradient biomaterials.
• The system offers enhanced precision, material compatibility, and scalability compared to existing methods.
• GRADE has broad potential to advance fundamental mechanobiology research and translational biomedical applications.