In Situ Microreaction Platform Based on Acoustic Droplet Manipulation for Ultra-High-Precision Multiplex Bioassay

Liquid droplets rectors have been used in clinical diagnosis, high throughput screening and bioassay. However, it is challenging for droplet reactors to be used in practical applications due to the difficulty of uniformly mixing ultrasmall volumes of samples and the lack of rapid and high-precision detection protocols. Here, we have developed an acoustic droplet system for rapid and efficient biological detection and chemical screening. By employing acoustic wave devices, rapid and nondestructive uniform mixing of ∼nL-μL droplets can be achieved. By the acoustophoretic force, the perturbation of the droplets can quickly concentrate the sample and increase the detection limit by five times. Through the color reaction and the coordinated detection of photodiodes, we have developed a biomarker detection protocol with short reaction time and high accuracy. As a proof-of-concept application, we demonstrated that this system can detect ultrasmall or low-abundance samples faster and more accurately, highlighting its wide application in analytical chemistry, basic research, and clinical medicine.