A colour enhanced light micrograph of sperm. The researchers were inspired by the design of ray sperm to create their microswimmers. Credit: Southern Illinois University / Science Photo Library

Microswimmers

11 September 2024

Researchers at the Hong Kong University of Science and Technology have developed a pioneering platform for the production of sperm-like micro-robots, aimed at enhancing precision in drug delivery. This breakthrough addresses the limitations of existing microfluidic devices by offering a streamlined process for creating these microswimmers.

The innovative platform, known as Vortex Turbulence-Assisted Microfluidics (VTAM), employs magnetic actuation to form microswimmers in a single step. These micro-robots feature flexible tails for controlled movement and core-shell heads for effective drug loading, enabling them to navigate complex environments within the body efficiently.

Inspired by the motility of ray fish sperm, the VTAM platform combines a traditional microfluidic chip with a vortex container, facilitating the creation of asymmetric sperm-like structures. This method not only simplifies production but also allows for adjustable morphology through vortex speed and solution concentration.

To enhance their functionality, the microswimmers are coated with a pH-sensitive membrane, allowing for controlled drug release in various pH environments. Initial tests have demonstrated their potential in delivering drugs precisely within bio-mimicking environments.

The research, led by Dr Yajing Shen and published in Nature Communications with Dr Xiong Yang and Dr Ron Tan as co-first authors, is a potentially significant development in biomedical engineering. The researchers hope that in vivo testing will demonstrate that these micro-robots will be effective in clinical settings.