1. Integrated Microsystem
Cells in, data out
Lyse
Separate
Detect
Model and Predict
Protein expression assays by conventional methods typically require ~ 106 cells.
An integrated system can reduce this by orders of magnitude

2. Detecting mass with a resonator
Micromechanical resonator
w2 = m k
Water
w2 =
m+mI k
mI in water ~ times greater than m
Quality factor in liquid is near unity
Sample
Resonance frequency: Dw
Frequency
Amplitude Dw
Gravimetric detection
principle: mass sensor with immobilized receptors
df/f=-1/2 dm/m
in vacuum: sensitivity limited by thermomechanical noise: limit??
problems:
physical: damping & large effective mass reduce sensitivity in liquid dramatically
technical: actuation & readout more difficult in conductive liquid
Amplitude
Frequency
Viscous damping from solution severely degrades mass resolution

3. The Suspended Microchannel Resonator
Confining the fluid to the inside of the resonator eliminates viscous drag Dw
Hollow resonator (concept)
mass sensitivity only determined by ratio of surface area to total mass (explain)
can be operated in vacuum
Burg and Manalis, Applied Physics Letters 2003

4. 500 nm
100 mm

5. Quality factor is independent of medium
No viscous damping
Quality factor is independent of medium

6. Biomolecular Detection
10-17 g/mm2
Burg and Manalis, Applied Physics Letters 2003

7. How sensitive is the suspended microchannel detector?
V~10 pL
V>10 mL
Quartz Crystal mBalance
Assume protein mass of 100 kD

8. Large-scale commercial manufacturing...
...with Innovative Micro Technology