Session: 07-02-01: Vibration and Acoustics in Biomedical Applications

Paper Number: 166370

Acoustic Cell Patterning-Assisted Digital Light Processing for Bioprinting Anisotropic Tissues 

Bioprinting technology has emerged as a transformative approach for fabricating engineered tissues and organs. This method can rapidly and precisely create complex biological structures and provide a scaffold for cellular organization and growth. Bioprinting technology has developed to be a powerful tool for regenerative medicine, tissue engineering, and drug screening. Unlike conventional scaffold fabrication techniques, bioprinting allows for the generation of intricate and patient-specific geometries that closely replicate native tissue architectures. Current various bioprinting techniques include inkjet bioprinting, extrusion-based bioprinting, laser-assisted bioprinting, droplet-based bioprinting, and stereolithography-based bioprinting. However, achieving biomimetic anisotropic characteristics of living tissues remains a significant challenge. Many native tissues, such as muscles, nerves, and blood vessels, exhibit specific arrangements that are crucial for their functions. To address this limitation, we propose an acoustic patterning technique integrated with a digital light processing (DLP)-based stereolithography bioprinting platform to fabricate anisotropic engineered tissues. Our method employs standing acoustic waves to achieve contactless, high-efficiency manipulation and alignment of cells directly within the Petri dish, enabling precise control over cellular alignment.

In this study, we designed and assembled an anisotropic bioprinting platform that combines our in-Petri-dish acoustic patterning device with a digital light processing (DLP) projector. Here, the bioink consists of the GelMA solution blended with living cells. Our acoustic patterning device comprises pairs of piezoelectric transducers at a frequency of 3.20 MHz and a glass-bottom Petri dish. Standing acoustic waves generated by transducers can manipulate and align cells within the bioink during the interval of the bioprinting process. Through proof-of-concept experiments, we validate the patterning effects of our acoustic patterning device. Our results confirmed the successful formation of line and dot patterns, which were consistent with analytical simulations. Furthermore, we evaluated our bioprinting platform in the aspects of printing resolution, three-dimensional (3D) scalability, and anisotropic printing capabilities. The results show this platform successfully produced 3D constructs ranging from millimeter to centimeter scale, including structures such as cones, nerve conduits, and vascular branches. Additionally, we assessed the viability and morphology of 3T3 fibroblast cells within the printed constructs. The results indicated cells embedded in printed constructs have high cell viability, clear cellular alignment, and good cellular extension in 3D environments. Therefore, we assembled successfully a nerve conduit with patterned cells. Our study presents an anisotropic bioprinting platform, utilizing an acoustic patterning method, capable of constructing anisotropic engineered tissues. We anticipate this platform offers new possibilities for 3D bioprinting applications in regenerative medicine, tissue engineering, and biomedical research.
 

Presenting Author: Bowen Cai Mississippi State University

Presenting Author Biography: Bowen Cai is a Ph.D. candidate in Aerospace Engineering at Mississippi State University, where he studies under Dr. Rani Sullivan and co-advises with Dr. Zhenhua Tian from Virginia Tech. he works as a Research Assistant at the Advanced Composite Institute of MSU.

His primary research focus is on acoustic-based nondestructive evaluation (NDE) and mechanical properties characterization for advanced materials. He has also conducted research in various acoustics-related fields, including acoustic levitation, acoustic manipulation, and ultrasonic imaging. In addition to exploring the unknown, he expands his expertise in commercial NDE technologies, including UT scanning, CT scanning, and immersed C-scanning. These skills have enabled him to assist MSU Advanced Composites Institute to do composite NDE standardized and assist NASA with customized NDE projects.

Authors:

Yingshan Du Virginia Tech
Bowen Cai Mississippi State University
Jiali Li Virginia Tech
Teng Li Virginia Tech
Luyu Bo Virginia Tech
Zhenhua Tian Virginia Tech