Serial Time-Encoded Amplified Microscopy (STEAM) toward High-
Throughput Identification and Enumeration of Rare CellsKeisuke Goda, Ali Motafakker-Fard, Kevin K. Tsia, and Bahram Jalali
Photonics Laboratory, Department of Electrical Engineering University of California, Los Angeles
CLEO Europe, Munich, Germany
June 14, 2009
Neural activity dynamics
Measuring Ca2+
transients from neurons
NAD(P)H waves traveling along a neutrophils long axis
Chemical dynamics in living cells
1 2
3 4
Microfluidics and high-throughput screening (HTS)
High Demand for High-Speed Imaging
Speed Limitations in Conventional Imaging
Traditional electronic image sensors are slow due to 1. Mechanical scanning (~10 kHz)2. Charge download time in CCD/CMOS cameras (~1 kHz)
CW LaserLaser
Scanner
Download
Data Rate = ~10 MHz
More importantly, there is the fundamental trade-off: Sensitivity vs.
Speed
Spectrally Encoded Imaging
1.
H. O. Bartelt, Opt. Commun. 27, 365 (1978)
image transmission using a single-mode fiber2.
G. J. Tearney, M. Shishkov, and B. E. Bouma, Opt. Lett. 27, 412 (2002)
miniature endoscopy3.
K. Shi, P. Li, S. Yin, and Z. Liu, Opt. Express. 12, 2096 (2004)
confocal microscopy
Lens
Diffraction
Grating
Sample
Broadband Optical Pulses
Probe Spectrum Reflected Spectrum Reconstructed Image
time
Amplified dispersive Fourier Transform
time
wavelength
time
wavelength wavelength
time
dispersionsample
Amplified dispersive Fourier transform
= an optical process that maps the spectrum of an optical pulse into a time-domain waveform using group-velocity dispersion and amplifies it simultaneously
1.
D. R. Solli, J. Chou, and B. Jalali, Nature Photon. 2, 48 (2008)2.
K. Goda, K. K. Tsia, and B. Jalali, Nature 458, 1145 (2009)
Real-time pulse-by-pulse spectrum analysis
http://images.google.com/imgres?imgurl=http://shop.c-illuminations.com/images/Spool.jpg&imgrefurl=http://shop.c-illuminations.com/index.php%3FcPath%3D27%26language%3Den%26osCsid%3Dcc2e0471cc8022ce142d5d5ffad26504&h=720&w=720&sz=19&hl=en&start=6&tbnid=YwUE470vDMvXAM:&tbnh=140&tbnw=140&prev=/images%3Fq%3Dfiber%2Boptic%2Bspool%26gbv%3D2%26ndsp%3D20%26hl%3Den%26sa%3DN
1.3 ns/nm
c
= 1565 nm
= 17 nm
Rep. Rate = 25 MHz
Serial Time-Encoded Amplified Microscopy
1DUltrafast Displacement Sensing
Ultrafast Barcode Reading
No need for mechanical scanning
No need for a CCD/CMOS camera
Frame Rate = Pulse Rep. Rate
K. Goda, K. K. Tsia, and B. Jalali, Appl. Phys. Lett. 93, 131109 (2008)
Serial Time-Encoded Amplified Microscopy
2D
Amplification in the dispersive fiber overcomes the fundamental trade-off
in imaging between sensitivity and speed.
Frame Rate = 6.1 MHz, Shutter Speed = 440 ps, Optical Image Gain = 25 dB
K. Goda, K. K. Tsia, and B. Jalali, Nature 458, 1145 (2009)
Serial Time-Encoded Amplified Microscopy
2D
K. Goda, K. K. Tsia, and B. Jalali, Nature 458, 1145 (2009)
Real-Time Observation of Fast Dynamic Events
Observation of Laser Ablation (Phase Explosion)
Ablation Laser Wavelength = 2.8 m Pulse Width = 5 ns Peak Power = ~ 1 MW
Real-Time Observation of Fast Dynamic Events
Ultrafast Microfluidic Flow of Particles
K. Goda, K. K. Tsia, and B. Jalali, Nature 458, 1145 (2009)
Particle Material = MetalParticle Size = 10
30 mFlow Speed = 2.4 m/s
Combined with Flow Cytometry
Fluidic system
LaserDe
tect
ors
OpticalFilters
Detector
Circulating Tumor Cells
Tumor
Need for identification and enumeration of rare cells in blood (e.g., circulating tumor cells)
STEAM enables ultrahigh-
throughput morphological characterization of these cells
Throughput = ~1 million cells/s
Summary & Future Work1.
Serial time-encoded amplified microscopy (STEAM) demonstrated
1D
Ultrafast barcode reading and displacement sensing
K. Goda, K. K. Tsia, and B. Jalali, Appl. Phys. Lett. 93, 131109 (2008)
2D
Continuous real-time observation of fast dynamical phenomena
K. Goda, K. K. Tsia, and B. Jalali, Nature 458, 1145 (2009)
2.
Future work
3D
High-throughput identification and enumeration of rare cells based on
3D morphology (to be published)
Combination with fluorescence microscopy
Slide Number 1Slide Number 2Speed Limitations in Conventional ImagingSpectrally Encoded ImagingAmplified dispersive Fourier TransformSerial Time-Encoded Amplified Microscopy 1DSerial Time-Encoded Amplified Microscopy 2DSerial Time-Encoded Amplified Microscopy 2DReal-Time Observation of Fast Dynamic EventsReal-Time Observation of Fast Dynamic EventsCombined with Flow CytometrySummary & Future Work