Recently Prof. Zhiming Wang from the Institute of Fundamental and Frontier Sciences (IFFS), has published an article titled “Gold Implanted Plasmonic Quartz Plate as a Launch Pad for Laser Driven Photoacoustic Microfluidic Pumps” inPNAS..IFFS is the first author affiliation, and Prof. Zhiming Wang and Prof. Jiming Bao from University of Houston are corresponding authors.
Enabled initially by the development of microelectromechanical systems, current microfluidic pumps still require advanced microfabrication techniques to create a variety of fluid-driving mechanisms. Here we report a generation of micropumps that involve no moving parts and microstructures. This micropump is based on a principle of photoacoustic laser streaming and is simply made of an Au-implanted plasmonic quartz plate. Under a pulsed laser excitation, any point on the plate can generate a directional long-lasting ultrasound wave which drives the fluid via acoustic streaming. Manipulating and programming laser beams can easily create a single pump, a moving pump, and multiple pumps. The underlying pumping mechanism of photoacoustic streaming is verified by high-speed imaging of the fluid motion after a single laser pulse. As many light-absorbing materials have been identified for efficient photoacoustic generation, photoacoustic micropumps can have diversity in their implementation. These laser-driven fabrication-free micropumps open up a generation of pumping technology and opportunities for easy integration and versatile microfluidic applications.