Analysis of Nanoparticle Enrichment Process by Considering Deformation of Droplet in Acoustic Microfluidic System

• Published in: Sensors and actuators. A. Physical. 2023-12, Vol.363, p.114731, Article 114731
• Main Authors: Huang, Lei, Zhou, Mingyong, Li, Luming, Peng, Tao, Jiang, Binyan
• Format: Article
• Language: English
• Subjects: acoustic microfluidic; droplet deformation; nanoparticle enrichment; streaming
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2023.114731

The highly efficient enrichment of particles in microfluidics is of great significance in various biochemical studies. Here, a Polydimethylsiloxane (PDMS) membrane structure with small holes is proposed to promote the spinning of droplets in the acoustic microfluidic system. A finite element method (FEM) model based on the moving mesh method is established to analyze the streamline and particle motion in the droplet. The spinning and the dynamic deformation of the droplet are considered comprehensively. Results show that the deformation and spinning of the droplet can promote the enrichment of particles, and the deformation of the droplet is the key reason for the enrichment of nanoparticles. By analyzing the spatial streamline inside the droplet, it is found that the particles will be enriched at a certain height from the bottom of the droplet, which is confirmed in the experiment and to date has not been reported before. Furthermore, the acoustic microfluidic system is manufactured, tested and applied to the enrichment of 100nm particles. The fluorescence intensity of the enriched particles can be used to characterize the concentration of the sample, indicating that the system is expected to be applied to the enrichment detection of biological particles such as extracellular vesicles. [Display omitted] •A moving mesh mode is proposed to analyze the spinning deformation of droplets.•PDMS film is applied to fix droplets and promote their spinning.•Droplets spinning deformation is the key reason for nanoparticles enriched.•Enrichment detection can be realized by the acoustic microfluidic system.