Manipulation of Cells in Ultrasonic Standing Waves

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Manipulation of Cells in Ultrasonic Standing
Waves

• Martyn Hill
• School of Engineering Sciences
• University of Southampton, UK

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Presentation Structure

• Standing Waves
• Radiation forces
• Lateral forces
• Streaming
• Example Applications
• Filtration and Manipulation
• Trapping and Agglomeration
• Cell Washing
• Biosensor Enhancement

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Cells in a standing wave radiation forces
Transducer
Reflector Layer
Carrier Layer
FluidLayer
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Cells in a standing wave streaming
Transducer
Reflector Layer
Carrier Layer
FluidLayer
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Filtration Trapping and Sedimentation
Flow
Doblhoffdier et al. Biotech Progress, 1994
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Filtration Laminar Flow Separator
Reflector
Inlet
Clear Outlet
Transducer
Hawkes Coakley, SA A 2001
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Microfabricated Separator

• Approximate Cavity Dimensions
• 8x4mm
• Depth 150-250 µm

Pyrex
Silicon
Inlet
Outlet
Transducer
Harris et al. SA B, 2003
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Filtration in a Porous Mesh
Flow
Wang, Feke et al. Biotech Progress, 2004 Gupta
Feke, Ultrasonics, 1997
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Cell Manipulation Using Plate Waves
Glass Plate with Bending Waves
Fluid
Reflector

• Particles Levitated within fluid and may be moved
  around laterally

Haake Dual, Ultrasonics, 2004
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Particle Trapping to Enhance Reactions
Thomas et al., Ultrasound in Med Biol,
1999 Wiklund et al., Jnl App Phys, 2004
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Trapping of Particles in a Flow
Flow
Morgan et al. Toxicology in Vitro, 2004
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Cell Washing

• Allows cells to be transferred from one fluid
  medium to another
• Chamber 250 microns deep

Cells in clear water
Clear water
Coloured Water
Cells in Coloured Water
Ultrasound on
Cells in coloured water
Clear Water
Hawkes et al. Lab on a Chip. 2004
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Cells in a ?/4 standing wave
Transducer
Reflector Layer
Carrier Layer
FluidLayer
Hawkes et al., Revista de Acustica, 2002 Hill,
JASA, 2003
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Moving spores onto a sensor surface
Immuno-sensor Surface
Reflector
Inlet
70 fold increase in sensitivity of spore detection
Transducer
Hawkes et al., Biosens Bioelect, 2004 Martin et
al., Biosens Bioelect, 2005
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Conclusions

• Ultrasonic standing waves provide a versatile
  tool for manipulating micron scale cells
• Significant scope for further development,
  particularly microsystems applications

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Cells in a standing wave