A novel acoustofluidic micropump to efficiently drive liquid in energy and space, providing strong technical support for portable systems

The miniaturization of health care, biomedical, and chemical systems is highly desirable for developing advanced technologies, encompassing micro-total analysis systems, lab-on-a-chip, organ-on-a-chip, point-of-care testing systems, and controlled drug delivery systems, among others. In this pursuit of miniaturization, the flexible manipulation and transportation of small amount of fluid is one of the crucial requirements. Micropumps play a pivotal role in this fulfilling process, assisting with the diverse functions, such as molecule detection, cell culture, drug screen, particle manipulations, etc.

Thus far, numerous types of micropumps have been proposed, including thermopneumatic, piezoelectric, electromagnetic, phase-change, dielectric elastomer, electroosmotic, electrohydrodynamic, and acoustofluidic micropumps. Nevertheless, due to various drawbacks with the existing micropumps, such as the intricate structure in the electromagnet micropump and the high working voltage in electrohydrodynamic and electroosmotic micropumps, most of them are still limited in laboratory usages. Consequently, micropumps remain one of the major bottlenecks in system miniaturization.

To tackle this limitation, a research team headed by Xuexin Duan from Tianjin University (China) has recently developed a novel acoustofluidic micropump to efficiently drive liquid in energy and space, providing robust technical support for portable systems.

To induce intense acoustic jet in a confined area, the researchers chose a film bulk acoustic resonator operating at a ultra-high frequency. To obtain plenty of unidirectional flow, the team introduced an inner boundary confinement concept to regulate the acoustic streaming for the first time. Consequently, the groundbreaking acoustic jet micropump (AcousJMP) exhibits high volume efficiencies and superior energy efficiency, which are all exceeding the reported values.

Capitalizing on its exceptional performance, a miniaturized AcousJMP has been successfully crafted into a wireless wearable device designed for the treatment of ocular diseases. Through rigorous animal experimentation and a preliminary test on human dry eye disease, the AcousJMP has demonstrated significant promise in enhancing medical care for patients with difficulties.

“In our ongoing research efforts, we aspire to integrate specialized control units, signal receiving and transmitting units, as well as sensors with the AcousJMP, transforming it into an intelligent device,” Duan said, “We firmly believe this endeavor will bring advanced technologies even closer to people's daily lives, offering them unprecedented convenience and support.”