Dynamics of Living cells

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Dynamics of Living cells in an Optical Trap
Giovanni Volpe, Gajendra P. Singh, Dmitri V.
Petrov
UB, 2006-05-29
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Preview
Photonic Force Microscope Dynamics of a Growing
Cell in an Optical Trap Optical Trapping
Dynamics
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Our Group
Prof. Dmitri Petrov
Giovanni Volpe
Dr. Caitriona Creely
Gajendra P. Singh
Asier Elejalde
Anna Morales
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Preview
Photonic Force Microscope Dynamics of a Growing
Cell in an Optical Trap Optical Trapping
Dynamics
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Forward Scattered Light detected by a Quadrant
Photodiode
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Brownian motion in optical traps
Harmonic Trap
Brownian Motion
Ghislain and Webb, Opt. Lett. (1993) 18, 1678
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Brownian motion in optical traps
Harmonic Trap
Brownian Motion
Ghislain and Webb, Opt. Lett. (1993) 18, 1678
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Brownian motion in optical traps
Harmonic Trap
Brownian Motion
Ghislain and Webb, Opt. Lett. (1993) 18, 1678
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Brownian motion in optical traps
Harmonic Trap
Brownian Motion
Ghislain and Webb, Opt. Lett. (1993) 18, 1678
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Brownian motion in optical traps
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Brownian motion in optical traps
Power Spectral Density
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Brownian motion in optical traps
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The Position of a Bead is Measured with Nanometer
Accuracy
Z mm
Z I II III IV X (I III) (II IV) Y
(I II) (III IV)
X mm
Y mm
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The PFM permits one to Measure pN/fN Forces
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Case Study Evanescent Wave Radiation Forces
Total Internal Reflection Angle
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Overview
Photonic Force Microscope Dynamics of a Growing
Cell in an Optical Trap Optical Trapping
Dynamics
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A Single Yeast Cell can Grow in an Optical Trap
Trapped
Free
Yeast Cell-Cycle
Budding Yeast cell
G1
Range of our experiments
S
M
G2
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Forward Scattered Light dected by a Quadrant
Photodiode
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The Organelles move towards the Focus in the
first 10 Minutes
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Z v
X v
Y v
Probability cloud shrinking due to the applied
optical potential
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The Budding changes the Cell Equilibrium Position
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Probability cloud movement due to the budding
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A Heat-treated Budding Cell does NOT show these
Effects
NO Shrinking at the beginning NO Changes over
Time Orientation Budding Higher Signals due to
heat-induced Opacity
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Implications
Be Careful in Acquiring Spectra! Asymmetric and
growing cells move in the optical trap The
scattered light follows different
paths Cell-Cycle Stages can be Probed Different
Cells can be Identified and Sorted
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Overview
Photonic Force Microscope Dynamics of a Growing
Cell in an Optical Trap Optical Trapping
Dynamics
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Optical Trapping Dynamics Setup
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OTD a time-of-flight method
This method is widely used in different area of
physics as atom cooling by measuring temperature
of cooled atoms, in infrared spectroscopy and
mass spectroscopy. Singer et al., J. Mod. Opt.
(2000) 47, 2921 Ignatovich et al., J. Mod. Opt.
(2003) 50, 1509
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OTD of a Polystyrene Sphere Calibration of the
Optical Trap
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OTD of a Yeast Cells Different cell-cycle stages
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OTD of a Yeast Cells Statistical Analysis
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Ongoing Works with OTD
Identification of blood cells Identification of
apoptosis stage in human cancer cells Study of
the elasticity of cells Your Suggestions?
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Dynamics of Living cells in an Optical Trap
Giovanni Volpe, Gajendra P. Singh, Dmitri V.
Petrov
UB, 2006-05-29