U.S. patent application number 11/087174 was filed with the patent office on 2005-07-28 for system and method for separating micro-particles.
This patent application is currently assigned to Genoptix, Inc. Invention is credited to Kibar, Osman.
Application Number | 20050164372 11/087174 |
Document ID | / |
Family ID | 26939358 |
Filed Date | 2005-07-28 |
United States Patent
Application |
20050164372 |
Kind Code |
A1 |
Kibar, Osman |
July 28, 2005 |
System and method for separating micro-particles
Abstract
A system and method for separating particles is disclosed in
which the particles are exposed to a moving light intensity pattern
which causes the particles to move at a different velocities based
on the physical properties of the particles. This system and method
allows particles of similar size and shape to be separated based on
differences in the particles dielectric properties.
Inventors: |
Kibar, Osman; (New York,
NY) |
Correspondence
Address: |
O'MELVENY & MEYERS
114 PACIFICA, SUITE 100
IRVINE
CA
92618
US
|
Assignee: |
Genoptix, Inc
|
Family ID: |
26939358 |
Appl. No.: |
11/087174 |
Filed: |
March 22, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11087174 |
Mar 22, 2005 |
|
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09843902 |
Apr 27, 2001 |
|
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60248451 |
Nov 13, 2000 |
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Current U.S.
Class: |
435/287.1 |
Current CPC
Class: |
G01N 30/00 20130101;
H05H 3/04 20130101; G01N 2015/149 20130101; G01N 30/02 20130101;
B01D 2015/3895 20130101; G01N 30/02 20130101 |
Class at
Publication: |
435/287.1 |
International
Class: |
C12M 001/34 |
Claims
What is claimed is:
1. A system for separating at least two particles, the particles
having different physical properties, the system comprising: means
for creating a light intensity pattern in the vicinity of the at
least two particles; and means for moving the light intensity
pattern with respect to the at least two particles.
2. The system according to claim 1, wherein the means for creating
a light intensity pattern comprises a light source for producing
two light beams aimed to interfere with each other in the vicinity
of the at least two particles.
3. The system according to claim 2, wherein the light beams
comprise coherent light beams.
4. The system according to claim 1, further comprising a beam
splitter and a reflector, wherein the light source is configured to
produce a light beam aimed at the beam splitter, the beam splitter
is configured to split the light beam into a first light beam
directed toward the at least two particles and a second light beam
directed toward the reflector, the reflector is configured to
redirect the second light beam toward the at least two particles
such that the first and second light beams interfere creating a
light intensity pattern in the vicinity of the at least two
particles.
5. The system according to claim 4, wherein the means for moving
comprises an actuator connected to the reflector for moving the
reflector.
6. The system according to claim 4, wherein the means for moving
comprises an actuator connected to the light source and beam
splitter for moving the light source and beam splitter.
7. The system according to claim 2, wherein the means for moving is
configured to move the light intensity pattern in space.
8. The system according to claim 2, wherein the means for moving is
configured to move the light intensity pattern in time.
9. The system according to claim 2, wherein the means for moving is
configured to fix the light intensity pattern and move the at least
two particles in space relative to the light intensity pattern.
10. The system according to claim 9 wherein the at least two
particles are held on a slide and the means for moving comprises an
actuator for moving the slide relative to the light intensity
pattern.
11. The system of claim 2 wherein the means for moving comprises a
phase modulator for modulating the phase of one of the two light
beams with respect the other.
12. The system of claim 2 wherein the light source comprises a
laser.
13. The system of claim 2 wherein the light beam is between 0.31
.mu.m and 1.8 .mu.m.
14. The system of claim 2 wherein the light beam is between 0.8
.mu.m and 1.8 .mu.m.
15. The system of claim 2 wherein the light beam has a wavelength
of 1.55 .mu.m.
16. The system of claim 1 wherein the means for creating a light
intensity pattern comprises a light source and an optical mask,
which can be a phase mask, an amplitude mask, or a holographic
mask, the light source being configured for producing a light beam
directed through the optical mask toward the at least two
particles.
17. The system of claim 1 further comprising a plurality of light
sources positioned adjacent to each other for producing a plurality
of light beams directed toward the at least two particles for
creating a light intensity pattern.
18. The system of claim 17 further comprising an actuator for
moving the plurality of light sources.
19. The system of claim 17 wherein the plurality of light beams are
aimed to slightly overlap each adjacent light beam in the vicinity
of the at least two particles, the plurality of light sources being
configured to be dimmed and brightened in a pattern for creating a
moving light intensity pattern.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No.
09/843,902, filed Apr. 27, 2001, which is is related to and claims
priority from provisional Application Ser. No. 60/248,451 filed
Nov. 13, 2000, which is incorporated by reference as if fully set
forth herein.
FIELD OF THE INVENTION
[0002] This invention relates to systems and methods for separating
micro-particles and/or nano-particles. More particularly, this
invention relates to systems and methods for separating
micro-particles and/or nano-particles by using a light source to
create a separation force on the particles based on their physical
properties.
BACKGROUND OF THE INVENTION
[0003] At the present, there are sorting methods to separate
particles, such as cells and other biological entities, based on
their size, density, and charge, but none that sort based on
optical dielectric properties. For example, laser tweezers have
been described that use the interaction of light with a particle to
move the particle around. However, in this case, a priori knowledge
of which particle to move is required for the tweezers to be used
as a sorting mechanism. In other words, tweezers are more of a
`manipulation and/or transportation`tool, rather than a `sorting`
tool. Thus, current methods and systems for separating particles
require prior identification of the particles to be separated.
[0004] There is a need for a system and method for separating
particles which does not require prior identification of the
particles to be separated There is also a need for a system and
method for separating particles which does not damage the
particles.
SUMMARY OF THE INVENTION
[0005] These needs and others are satisfied by a system and method
for separating particles according to the present invention which
comprises means for creating a light intensity pattern in the
vicinity of the particles and means for moving the light intensity
pattern with respect to the particles. The means for creating a
light intensity pattern can comprise a light source for producing
two light beams aimed to interfere with each other in the vicinity
of the two particles.
[0006] In one embodiment, the system comprises a beam splitter and
a reflector. In this embodiment, the light source is configured to
produce a light beam aimed at the beam splitter. The beam splitter
is configured to split the light beam into a first light beam
directed toward the particles and a second light beam directed
toward the reflector. The reflector is configured to redirect the
second light beam toward the particles such that the first and
second light beams interfere creating a light intensity pattern in
the vicinity of the particles.
[0007] An actuator can be connected to the reflector for moving the
reflector to move the light intensity pattern. Alternatively, the
actuator can be connected to the light source and beam splitter for
moving the light source and beam splitter.
[0008] It is also possible to move the particles relative to the
light intensity pattern to create the moving light intensity
pattern. In order to do this, the particles can be carried on a
slide connected to an actuator configured to move the slide
relative to the light intensity pattern.
[0009] The light intensity pattern can also be moved by using a
phase modulator to modulate the phase of one of the two light beams
with respect to the other. This causes the light intensity pattern
created by the interference of the light beams to move spatially.
The phase modulator can be place in the path of either the first
light beam or second light beam. Alternatively, an amplitude
modulator can be used, in which case the interference pattern will
move temporally.
[0010] Any material that responds to optical sources may be
utilized with these inventions. In the biological realm, examples
would include cells, organelles, proteins and DNA, and in the
non-biological realm could include metals, semiconductors,
insulators, polymers and other inorganic materials.
[0011] Preferably, the light source comprises a laser producing a
light beam having a wavelength of between 0.31 .mu.m and 1.8 .mu.m.
Using a light beam in this wavelength range minimizes the chance
that damage will be caused to the particles if they are living
cells or biological entities. Even more preferably, the light beam
wavelength range could be 0.8 .mu.m and 1.8 .mu.m. Good,
commercially available lasers are available which produce a light
beam having a wavelength of 1.55 .mu.m.
[0012] In an alternative embodiment, the system comprises a light
source and an optical mask. The light source is configured for
producing a light beam directed through the optical mask toward the
particles. The optical mask creates a light intensity pattern in
the vicinity of the particles. An actuator can be connected to the
light source and optical mask for moving the light source and
optical mask to create a moving light intensity pattern.
Alternatively, the optical mask can be specially configured for
producing a moving light intensity pattern in the vicinity of the
at least two particles. Another alternative is to include a phase
modulator positioned in the light beam path for modulating the
phase of the light beam to create a moving light intensity
pattern.
[0013] In yet another embodiment the system can comprise a
plurality of light sources positioned adjacent to each other for
producing a plurality of light beams directed toward the particles
The light beams can be aimed to slightly overlap each other to
create a light intensity pattern. An actuator can be included for
moving the plurality of light sources, thus causing the light
intensity pattern to move spatially. Alternatively, the light beams
can be dimmed and brightened in a pattern for creating a temporally
moving light intensity pattern.
[0014] A method for separating particles according to the present
invention comprises the steps of applying a light source to create
a light intensity pattern, exposing particles to the light
intensity pattern producing force on each particle and moving the
light intensity pattern with respect to the particles causing the
particles to move with the light intensity pattern at velocities
related to their respective physical properties. If the particles
have different physical properties they will move at a different
velocity causing the particles to separate.
[0015] Preferably, the step of applying a light source comprises
interfering at least two optical light beams as discussed herein
with respect to one embodiment of a system according to the present
invention.
[0016] Alternatively, the step of applying a light source can
comprise using an optical mask to create the light intensity
pattern. The optical mask can comprise an amplitude mask, a phase
mask, a holographic mask, or any other suitable mask for creating a
light intensity pattern.
[0017] In another embodiment of a method according to the present
invention the step of applying a light source can comprise
periodically dimming and brightening a plurality of light sources
to create the light intensity pattern.
[0018] Preferably, the light intensity pattern comprises at least
two peaks and at least two valleys. The light intensity pattern can
be periodic, sinusoidal, nonsinusoidal, constant in time, or
varying in time. If the light intensity pattern is periodic, the
period can be optimized to create separation between particles.
[0019] In one embodiment, the method comprises moving the light
intensity pattern at a constant velocity. The velocity of the light
intensity pattern can be optimized to cause separation based on the
physical properties of the particles.
[0020] In an alternative embodiment, the method comprises allowing
the at least two particles to separate, and then suddenly "jerking"
the light intensity pattern to cause particles with different
physical properties to fall into different valleys of a potential
pattern created by the light intensity pattern.
[0021] The method light intensity pattern can be tuned to a
resonant frequency corresponding to the physical properties of one
type of particles to optimize separation of that type of particle.
The light intensity pattern can be applied in multiple dimensions
and the period of the light intensity pattern can be varied in each
dimension.
[0022] The particles can be carried in a medium, such as a fluidic
medium, which can be either guided or non-guided. If the medium is
guided it can include fluidic channels.
[0023] The method can also include superimposing a gradient onto
the light intensity pattern. The gradient can be spatially constant
or varying and can comprise temperature, pH, viscosity, etc.
Additional external forces can also be applied, such as magnetism,
electrical forces, gravitational forces, fluidic forces, frictional
forces, electromagnetic forces, etc., in a constant or varying
fashion.
[0024] A monitoring and/or feedback system can also be included for
monitoring the separation between particles and providing feedback
information as to separation and location of particles.
[0025] Further object, features and advantages of the present
invention will become apparent from the following description and
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIGS. 1A, 1B, 2A, 2B and 3 are block diagrams of various
embodiments of a system according to the present invention;
[0027] FIG. 4A is a graphical depiction of an optical grating
produced light intensity pattern generated by a system according to
the present invention.
[0028] FIG. 4B is a graphical depiction of an energy pattern
corresponding to the light intensity pattern of FIG. 4A.
[0029] FIG. 4C is a graphical depiction of a potential energy
pattern corresponding to the light intensity pattern of FIG.
4A.
[0030] FIGS. 5A, 5B and 5C are a graphical depiction of a moving
potential energy pattern generated by a system and method according
to the present invention.
[0031] FIG. 6 is an enlarged sectional view of a fluidic
micro-channel with a graphical depiction of the moving light
intensity pattern of FIG. 4A superimposed in the fluidic
micro-channel.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] In accordance with the present invention, a system and
method for separating particles is described that provides distinct
advantages when compared to those of the prior art. The invention
can best be understood with reference to the accompanying drawing
figures.
[0033] Referring now to the drawings, a system according the
present invention is generally designated by reference numeral 10.
The system 10 is configured to generate a moving light intensity
pattern that produces a force on the particles to be separated. The
force causes the particles to move at velocities related to certain
physical properties of each particle, such as the particle's
optical dielectric constant. Particles with different physical
properties will move at different velocities causing the particles
to separate based on their physical properties.
[0034] One embodiment of a system 10 according to the present
invention is shown in FIG. 1. In this embodiment, the system 10
comprises a light source 12, a beam splitter 14, and a reflector
16. A motor 18 can be connected to the reflector 16 for moving or
rotating the reflector 16. A control system 19 is connected to the
motor 18 for controlling operation of the motor 18 and thus
movement of the reflector 16.
[0035] The particles to be separated can be placed in a medium on a
slide 22. In one embodiment of the invention, the slide 22 includes
a non-guided fluidic medium, such as water. In another embodiment,
shown in FIG. 6, the slide 22 includes fluidic channels 500, 502
and 504 through which the particles 410, 412 travel.
[0036] The medium can be non-guided or guided. One example of a
guided medium is a medium comprising fluidic channels as is well
known in the art.
[0037] The light source 12 is positioned to produce a light beam 24
that is aimed at the beam splitter 14. The beam splitter 14 splits
the light beam 24 into two light beams 26, 28 and directs one of
the light beams 26 toward the reflector 16 and the other light beam
28 toward the slide 22. The reflector 16 redirects light beam 26
toward the slide 22. The light beams 26, 28 are focused near the
particles and aimed to interfere with each other to create a light
intensity pattern near the particles.
[0038] The motor 18 can be used to move or rotate the reflector 16,
which causes the light intensity pattern to move in space. A
control system 19 is connected to the motor 18 to control operation
of the motor 18. By moving the light intensity pattern in space and
keeping the slide 22 fixed, forces created on the particles by the
light intensity pattern cause the particles to move at velocities
related to each particle's physical properties as described herein.
The particles can also be caused to move by fixing the light
intensity pattern in space and mechanically moving the slide 22
carrying the particles. This causes the light intensity pattern to
move in space relative to the particles.
[0039] Alternatively, motor 18 can be connected to the light source
12 and beam splitter 14. In this embodiment the light source 12 and
beam slitter 14 can be moved or rotated by the motor 18. This
causes light beam 28 to move relative to light beam 26, which, in
turn, causes the light intensity pattern to move.
[0040] In another embodiment, shown in FIG. 1B, the light intensity
pattern is moved by modulating the relative phase of the light
beams 26, 28. In this embodiment, a phase modulator 20 is
positioned in the path of light beam 26. The phase modulator 20 is
configured to modulate the phase of light beam 26 relative to the
phase of light beam 28. A control system 19 is connected to the
phase modulator 20 for controlling operation of the phase modulator
20. Alternatively, the phase modulator 20 can be positioned in the
path of light beam 28 for modulating the phase of light beam 28
relative to the phase of light beam 26.
[0041] Modulating the phases of light beams 26 and 28 relative to
each other causes the light intensity pattern created by the
interference of light beams 26 and 28 to move. Moving the light
intensity pattern relative to the particles creates forces on the
particles related to the physical properties of each particle. As
described above, these forces will cause particles with different
physical properties to move at different relative velocities.
[0042] Alternatively, an amplitude modulator can be used instead of
the phase modulator 20. The amplitude modulator can be used for
modulating the amplitude of the light beams 24, 26, 28 thus
creating a moving light intensity pattern.
[0043] Preferably, the light source 12 comprises a laser for
producing light beams 26 and 28 coherent with respect to each
other. Alternatively, two light sources could be used to produce
light beams 26 and 28.
[0044] In applications where the particles are biological material
or living cells, it is preferable that the laser produce light
beams 26, 28 having a wavelength of between 0.3 .mu.m and 1.8 .mu.m
so as not to generate excessive heat that could damage the
particles. More preferably, the laser would produce light beams 26,
28 having a wavelength of greater than 0.8 .mu.m. Very good lasers
are commercially available which produce light beams 26, 28 having
a wavelength of 1.55 .mu.m and would be appropriate for use in a
system 10 according to the present invention. Alternatively, the
light source 12 can produce incoherent light beams 26, 28.
[0045] In another embodiment of the invention, shown in FIG. 2A,
the system 110 comprises a light source 112 and an optical mask
114. A motor 116 can be connected to the light source 112 and
optical mask 114 for moving or rotating the light source 112 and
optical mask 114. A control system 119 is connected to the motor
116 for controlling operation of the motor 116 and thus movement of
the light source 112 and optical mask 114. In this embodiment, the
light source 112 produces a light beam 118 that is aimed through
the optical mask 114 toward a slide 120 holding the particles to be
separated.
[0046] The optical mask 114 is configured to create a light
intensity pattern near the particles. The motor 116 can be used to
move or rotate the light source 112 and optical mask 114 thus
causing the light intensity pattern to move. Alternatively, the
light intensity pattern can be fixed in space and the slide 120 can
be moved producing relative motion between the light intensity
pattern and the particles.
[0047] The optical mask 114 can comprise an optical phase mask, an
optical amplitude mask, a holographic mask or any similar mask or
device for creating a light intensity pattern. In another
alternative embodiment, the optical mask 114 can be specially
configured to produce a moving light intensity pattern. This type
of optical mask 114 can be produced by writing on the mask with at
least two light beams. In essence, one light beam writes on the
mask to create the light intensity pattern and the other mask
erases the mask. In this embodiment, a new light intensity pattern
is created each time the mask is written upon.
[0048] In the embodiment shown in FIG. 2B, a phase modulator 122 is
used to create the moving light intensity pattern. The phase
modulator 122 is positioned between the light source 112 and the
optical mask 114 such that light beam 118 is directed through the
phase modulator 112. A control system 119 is connected to the phase
modulator 122 for controlling operation of the phase modulator
112.
[0049] In yet another embodiment, shown in FIG. 3, the system 10
comprises a plurality of light sources 212 positioned adjacent to
each other such that they produce light beams 214 directed toward a
slide 216 holding the particles to be separated. In one embodiment,
the light sources 212 are aimed to create light beams 214 that
overlap each other to produce a light intensity pattern.
[0050] An actuator 218 can be attached to the light sources 212 for
moving or rotating the light sources 212 to move the light
intensity pattern with respect to the slide 216. A control system
219 is connected to the actuator 218 for controlling operation of
the actuator 218. For example, motors (not shown) can be attached
to each of the light sources 212. The light intensity pattern can
also be moved relative to the slide 216 by modulating phase, moving
the slide 216 relative to the light sources 212 or in any other
described herein.
[0051] Alternatively, the light sources 212 can be aimed such that
the light beams 214 slightly overlap each other near the slide 216.
A light intensity pattern can be created by switching the light
sources to be dimmed and brightened in certain patterns to give the
appearance of a moving light intensity pattern. For example, in one
embodiment the light sources 212 are dimmed and brightened such
that at any given moment in time, whenever one light source is
bright, all adjacent light sources are dim and when the first light
source is dim the adjacent light sources are bright.
[0052] In operation, focusing a light beam in the vicinity of a
particle causes the light beam to interact with optical dipoles
inside the particle. Maximum intensity of a light beam is achieved
at the focal point of the beam. The particle tends to move toward
the point of maximum intensity of the light beam because the
minimum energy for the overall system is achieved when the dipoles
of the particle reside where the maximum intensity of the light
beam occurs.
[0053] A system according to the present invention, such as those
described infra, are configured to create a variable light
intensity pattern. FIGS. 4A, 4B, and 4C show a periodic light
intensity pattern 400, the force 402 exerted on a particle by the
light intensity pattern 400, and the potential 404 exerted on a
particle by the light intensity pattern 400, respectively. The
light intensity pattern 400 shown in FIG. 4A is sometimes referred
to as an optical grating.
[0054] Particles subjected to the light intensity pattern 400 of
FIG. 4A tend to move toward the peak intensity points 406. The
wells 408 of the potential pattern 404 shown in FIG. 4C represent
points where the overall system energy is at a minimum. Thus, a
particle will tend to move toward the wells 408 of the potential
pattern 404.
[0055] Light intensity patterns 400 created according to the
present invention can comprise at least two peaks 406 and at least
two valleys 407. Suitable light intensity patterns 400 can be
periodic, sinusoidal, nonsinusoidal, constant in time or varying in
time. If the light intensity pattern 400 is periodic, the period
can be optimized to create separation between particles exposed to
the light intensity pattern 400. For example, for large particles
the period length can be increased to increase the size of wells
408 in the corresponding potential pattern 404 to accommodate the
large particles.
[0056] FIGS. 5A, 5B and 5C show two particles 410, 412 exposed to a
potential pattern 406. In this figure, particles 410 and 412 are of
similar size and shape but have different dielectric constants.
[0057] As described infra, moving the light intensity pattern 400
and consequently the potential 406 created by the light intensity
pattern 400, relative to particles 410, 412 exposed to the light
intensity pattern 400 causes the particles 410, 412 to move at
velocities related to the physical properties of the particles 410,
412. For example, the force acting on a particle is proportional to
the dielectric constant of the particle. More specifically, the
force is proportional to (E.sub.p-E.sub.m)/(E.sub.p+2 E.sub.m).
Thus, two particles 410, 412 of similar size and shape having
different dielectric properties will travel at different velocities
when exposed to a moving light intensity pattern 400.
[0058] The potential 406 created by the light intensity pattern 400
causes the particles 410, 412 to move toward wells 408 in the
potential pattern 406. Because the light intensity pattern 400, and
consequently the potential pattern 406, are moving, the particles
410, 412 "surf" on waves created in the potential pattern 406. The
waves include peaks 414 of high potential and wells 408 of low
potential.
[0059] The particles 410, 412 move with the potential pattern 406
at velocities related to the particles 410, 412 physical
properties. One such physical property is the dielectric constant
of the particles 410, 412. Because the dielectric constants of
particles 410 and 412 are different, they will move at different
velocities when exposed to the potential pattern 406 created by the
light intensity pattern 400.
[0060] In one embodiment, the light intensity pattern 400, and
consequently the potential pattern 406, is moved at a constant
velocity. The velocity can be optimized to cause separation of the
particles 410, 412 based on the particles' 410, 412 physical
properties. For example, a maximum velocity exists for each
particle 410, 412 such that if the maximum velocity is exceeded,
the peak 414 on which the particle 410 or 412 is "surfing" will
pass the particle 410 or 412 causing the particle 410 or 412 to
fall into the preceding well 408.
[0061] In this embodiment, a velocity is chosen between the maximum
velocities of particles 410 and 412. Assuming the maximum velocity
of particle 412 is higher than the maximum velocity of particle
410, when exposed to the potential pattern 406 shown in FIG. 5A,
particle 412 will "surf" on peak 414 and particle 410 will fall
behind into well 408 thus separating particles 410 and 412 based on
their physical properties.
[0062] In another embodiment is shown in FIGS. 5B and 5C. In this
embodiment, particles 410 and 412 are exposed to potential pattern
406 for a predetermined amount of time to allow the particles 410,
412 to separate slightly as shown in FIG. 5B. Once the particles
410, 412 have separated slightly, the potential pattern 406 is
"jerked" forward a predetermined difference such that the particles
410, 412 are positioned on opposites sides of peak 414. Once the
particles are positioned on opposite sides of peak 414, the forces
exerted on the particles 410, 412 cause them to fall into wells 408
on opposite sides of peak 414 thus separating the particles 410 and
412 based on their physical properties.
[0063] In one application of the invention, shown in FIG. 6, a
moving light intensity pattern 400 can be superimposed onto a
fluidic channel guided medium 506 having fluidic channels 500, 502
and 504. The channels 500, 502 and 504 are arranged in a T-shape
with the light intensity pattern 400 being superimposed on the
branch of the "T" (i.e. the junction between channels 500, 502, and
504).
[0064] The particles 410, 412 travel from channel 500 into the
light intensity pattern 400. The light intensity pattern 400 is
configured to move particles 410 and 412 in different directions,
as described infra, based on the particles' 410, 412 physical
properties. In this case, the light intensity pattern 400 is
configured to move particle 412 into channel 502 and particle 410
into channel 504. In this manner, the particles 410, 412 can be
separated and collected from their corresponding channels 504, 502,
respectively.
[0065] Using an application such as this, the light intensity
pattern can be configured to move particles 410 having a physical
property below a certain threshold into one channel 504 and
particles 412 having a physical property above the threshold into
the other channel 502. Thus, various particles can be run through
channel 500 and separated based on a certain threshold physical
property. Multiple fluidic channel guided mediums 500 can be
connected to channels 502 and/or 504 to further sort the separated
particles 410, 412 based on other threshold physical
properties.
[0066] Additional optimization can be done to facilitate particle
sorting. For example, each particle 410, 412 has a specific
resonant frequency. Tuning the wavelength of the light intensity
pattern 400 to the resonant frequency of one of the particles 410
or 412 increases the force exerted on that particle 410 or 412. If,
for example, the frequency of the light intensity pattern is tuned
to the resonant frequency of particle 412, the velocity at which
particle 412 travels is increases, thus increasing the separation
between particles 410 and 412.
[0067] Other forces can also be superimposed onto the particles
410, 412 to take advantage of additional differences in the
physical properties of the particles 410, 412. For example, a
gradient, such as temperature, pH, viscosity, etc., can be
superimposed onto the particles 410, 412 in either a linear or
non-linear fashion. External forces, such as magnetism, electrical
forces, gravitational forces, fluidic forces, frictional forces,
electromagnetic forces, etc., can also be superimposed onto the
particles 410, 412 in either a linear or non-linear fashion.
[0068] The light intensity pattern 400 and/or additional forces can
be applied in multiple dimensions (2D, 3D, etc.) to further
separate particles 410, 412. The period of the light intensity
pattern 400 can be varied in any or all dimensions and the
additional forces can be applied linearly or non-linearly in
different dimensions.
[0069] A monitoring system, not shown, can also be included for
tracking the separation of the particles 410, 412. The monitoring
system can provide feedback to the system and the feedback can be
used to optimize separation or for manipulation of the particles
410, 412.
[0070] It will be apparent to those skilled in the art that
modifications may be made without departing from the spirit and
scope of the invention. Accordingly, it is not intended that the
invention be limited except as may be necessary in view of the
appended claims.
* * * * *