Acoustic focusing with engineered node locations for high-performance microfluidic particle separation.
Analyst
; 139(5): 1192-200, 2014 Mar 07.
Article
em En
| MEDLINE
| ID: mdl-24448925
ABSTRACT
Acoustofluidic devices for manipulating microparticles in fluids are appealing for biological sample processing due to their gentle and high-speed capability of sorting cell-scale objects. Such devices are generally limited to moving particles toward locations at integer fractions of the fluid channel width (1/2, 1/4, 1/6, etc.). In this work, we introduce a unique approach to acoustophoretic device design that overcomes this constraint, allowing us to design the particle focusing location anywhere within the microchannel. This is achieved by fabricating a second fluid channel in parallel with the sample channel, separated from it by a thin silicon wall. The fluids in both channels participate to create the ultrasound resonance, while only one channel processes the sample, thus de-coupling the fluidic and acoustic boundaries. The wall placement and the relative widths of the adjacent channels define the particle focusing location. We investigate the operating characteristics of a range of these devices to determine the configurations that enable effective particle focusing and separation. The results show that a sufficiently thin wall negligibly affects focusing efficiency and location compared to a single channel without a wall, validating the success of this design approach without compromising separation performance. Using these principles to design and fabricate an optimized device configuration, we demonstrate high-efficiency focusing of microspheres, as well as separation of cell-free viruses from mammalian cells. These "transparent wall" acoustic devices are capable of over 90% extraction efficiency with 10 µm microspheres at 450 µL min(-1), and of separating cells (98% purity), from viral particles (70% purity) at 100 µL min(-1).
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Tamanho da Partícula
/
Acústica
/
Vírus da Dengue
/
Técnicas Analíticas Microfluídicas
Limite:
Animals
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article