Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Intra-droplet acoustic particle focusing : simulations and experimental observations

Fornell, Anna LU ; Garofalo, Fabio LU ; Nilsson, Johan LU ; Bruus, Henrik and Tenje, Maria LU (2018) In Microfluidics and Nanofluidics 22(7).
Abstract

The aim of this paper is to study resonance conditions for acoustic particle focusing inside droplets in two-phase microfluidic systems. A bulk acoustic wave microfluidic chip was designed and fabricated for focusing microparticles inside aqueous droplets (plugs) surrounded by a continuous oil phase in a 380-μm-wide channel. The quality of the acoustic particle focusing was investigated by considering the influence of the acoustic properties of the continuous phase in relation to the dispersed phase. To simulate the system and study the acoustic radiation force on the particles inside droplets, a simplified 3D model was used. The resonance conditions and focusing quality were studied for two different cases: (1) the dispersed and... (More)

The aim of this paper is to study resonance conditions for acoustic particle focusing inside droplets in two-phase microfluidic systems. A bulk acoustic wave microfluidic chip was designed and fabricated for focusing microparticles inside aqueous droplets (plugs) surrounded by a continuous oil phase in a 380-μm-wide channel. The quality of the acoustic particle focusing was investigated by considering the influence of the acoustic properties of the continuous phase in relation to the dispersed phase. To simulate the system and study the acoustic radiation force on the particles inside droplets, a simplified 3D model was used. The resonance conditions and focusing quality were studied for two different cases: (1) the dispersed and continuous phases were acoustically mismatched (water droplets in fluorinated oil) and (2) the dispersed and continuous phases were acoustically matched (water droplets in olive oil). Experimentally, we observed poor acoustic particle focusing inside droplets surrounded by fluorinated oil while good focusing was observed in droplets surrounded by olive oil. The experimental results are supported qualitatively by our simulations. These show that the acoustic properties (density and compressibility) of the dispersed and continuous phases must be matched to generate a strong and homogeneous acoustic field inside the droplet that is suitable for high-quality intra-droplet acoustic particle focusing.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Acoustophoresis, Droplets, Particle manipulation, Two-phase microfluidics, Ultrasound
in
Microfluidics and Nanofluidics
volume
22
issue
7
article number
75
publisher
Springer
external identifiers
  • scopus:85049355516
ISSN
1613-4982
DOI
10.1007/s10404-018-2094-9
language
English
LU publication?
yes
id
5b9b4365-2988-427e-8c95-0708604e3218
date added to LUP
2018-07-13 10:57:17
date last changed
2022-04-25 08:18:37
@article{5b9b4365-2988-427e-8c95-0708604e3218,
  abstract     = {{<p>The aim of this paper is to study resonance conditions for acoustic particle focusing inside droplets in two-phase microfluidic systems. A bulk acoustic wave microfluidic chip was designed and fabricated for focusing microparticles inside aqueous droplets (plugs) surrounded by a continuous oil phase in a 380-μm-wide channel. The quality of the acoustic particle focusing was investigated by considering the influence of the acoustic properties of the continuous phase in relation to the dispersed phase. To simulate the system and study the acoustic radiation force on the particles inside droplets, a simplified 3D model was used. The resonance conditions and focusing quality were studied for two different cases: (1) the dispersed and continuous phases were acoustically mismatched (water droplets in fluorinated oil) and (2) the dispersed and continuous phases were acoustically matched (water droplets in olive oil). Experimentally, we observed poor acoustic particle focusing inside droplets surrounded by fluorinated oil while good focusing was observed in droplets surrounded by olive oil. The experimental results are supported qualitatively by our simulations. These show that the acoustic properties (density and compressibility) of the dispersed and continuous phases must be matched to generate a strong and homogeneous acoustic field inside the droplet that is suitable for high-quality intra-droplet acoustic particle focusing.</p>}},
  author       = {{Fornell, Anna and Garofalo, Fabio and Nilsson, Johan and Bruus, Henrik and Tenje, Maria}},
  issn         = {{1613-4982}},
  keywords     = {{Acoustophoresis; Droplets; Particle manipulation; Two-phase microfluidics; Ultrasound}},
  language     = {{eng}},
  month        = {{07}},
  number       = {{7}},
  publisher    = {{Springer}},
  series       = {{Microfluidics and Nanofluidics}},
  title        = {{Intra-droplet acoustic particle focusing : simulations and experimental observations}},
  url          = {{http://dx.doi.org/10.1007/s10404-018-2094-9}},
  doi          = {{10.1007/s10404-018-2094-9}},
  volume       = {{22}},
  year         = {{2018}},
}