United States Patent
`(12)
`(10) Patent No.:
`US 7,241,988 B2
`
`Gruber et al.
`(45) Date of Patent:
`Jul. 10, 2007
`
`US007241988B2
`
`(54) SYSTEM AND METHOD OF SORTING
`MATERIALS USING HOLOGRAPHIC LASER
`STEERING
`
`(75)
`
`Inventors: Lewis Gruber, Chicago, IL (US);
`Kenneth Bradley’ Chicago’ IL (Us);
`Ward Lopes, Chicago, IL (US); Robert
`W. Lancelot, Chicago, IL (US); Joseph
`S- Plewa, Chicago, IL (US); David G.
`Grier, Chicago, IL (US)
`
`(73) Assignee: Arryx, Inc., Chicago, IL (US)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term ofthis
`patent is extended or adjusted under 35
`U’S’C’ 154001)}, 110 days’
`,
`.
`..
`(21) Appl NO . 10/630 904
`
`(22)
`
`Filed:
`
`Jul. 31, 2003
`
`(65)
`
`Prior Publication Data
`
`US 2004/0089798 A1
`
`May 135 2004
`
`(60)
`
`(51)
`
`Related US. Application Data
`.
`.
`.
`.
`Prov1s1onal app11cat1on No. 60/399,386, filed on Jul.
`31’ 2002‘
`Int. Cl.
`(2006.01)
`G01N 21/63
`(52) US. Cl.
`..................... 250/251; 435/7.l; 435/2887
`(58) Field of Classification Search ................. 250/251,
`250/484’4’ 252/3014 S5 3014 H5 382/1415
`.
`.
`382/143} 422/100
`See app11cat1on file for complete search h1story.
`References Cited
`U.S. PATENT DOCUMENTS
`
`(56)
`
`3,649,829 A
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`1/1984 Iriguchi
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`3133; gfiiiaklt :tlal'
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`1/1993 Touge et a1.
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`3/1993 Tycko
`5,194,909 A
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`5,229,297 A
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`5,483,469 A
`4/1997 Weetall et a1.
`5,620,857 A
`10/1997 Ulmer
`5,674,743 A
`9/1998 Chow et a1.
`5,800,690 A
`11/1998 Austin 6t al~
`5,837,115 A
`13/133: 3011515431} 1
`2,373,832; 2
`os an1ec e a .
`,
`,
`5,966,457 A * 10/1999 Lemelson ................... 382/141
`H001960 H
`6/2001 Conrad et a1.
`
`(Continued)
`OTHER PUBLICATIONS
`
`”,
`les In Nucleic Acid Chemis
`Paul O.P. Ts’o, “Basic Princi
`try
`P
`National Library of Medicine, 1974, pp. 311-387, Academic Press,
`Inc., New York, New York.
`
`Primary ExamineriNikita Wells
`Assistant Examinerilohnnie L Smith, 11
`(74) Attorney, Agent, or FirmiAkerman Senterfitt; Jean C.
`Edwards, Esq.
`(57)
`
`ABSTRACT
`
`The present invention employs a beam steering apparatus to
`isolate valuable cells from other cells, tissues, and contami-
`nants. In one embodiment,
`the system balances optical
`trapping against biasing flow to parallelize cell sorting under
`the flexible control of computer program-directed traps
`which differentially manipulate cells based on their compo-
`sition or labels to direct separation.
`
`71 Claims, 9 Drawing Sheets
`
`Microscope
`
`Illumination
`
`
`
`
`
` Rotating
`
`509
`Nosepiece
`
`502
`
`511
`
`510
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`
`
`Exhibit No. 1016
`
`PGR of US. Patent 8,933,395
`
`

`

`US 7,241,988 B2
`
`Page 2
`
`US. PATENT DOCUMENTS
`
`6,368,871 Bl
`6,432,630 Bl
`6451364 Bl
`6506509 B1
`6,524,860 Bl
`6,637,463 B1
`6,727,451 B1
`6,815,664 B2
`6,833,542 B2
`6,838,056 B2 *
`
`4/2002 Christel 6t 41.
`8/2002 Blankenstem
`9/2002 131111112“ et 3L
`1/2003 Wéda et 31'
`”003 se‘.de1 et 31'
`10/2003 Le1etal.
`4/2004 Fuhr et a1.
`“/2004 Wang et 31.
`12/2004 Wang et a1.
`1/2005 Foster
`........................ 422/100
`
`6,944,324 B2 *
`2002/0058332 A1
`2002/0176069 A1
`2003/0032204 A1*
`2003/0047676 A1
`2003/0186426 A1
`2005/0061962 A1*
`2005/0121604 A1*
`
`.................. 382/143
`9/2005 Tran et al.
`5/2002 Quake et a1.
`11/2002 Hansen etal.
`2/2003 Walt et al.
`.................. 436/518
`3/2003 Grier et al.
`10/2003 Brewer et al.
`3/2005 Mueth etal.
`6/2005 Mueth et a1.
`
`............... 250/251
`250/251
`
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`2006/0152707 A1
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`7/2006 Kanda
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`* cited by examiner
`
`

`

`U.S. Patent
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`Jul. 10, 2007
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`Sheet 1 of 9
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`US 7,241,988 B2
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`FIG. 1
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`U.S. Patent
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`Jul. 10, 2007
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`Sheet 2 of 9
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`US 7,241,988 B2
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`U.S. Patent
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`Jul. 10, 2007
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`Sheet 3 of 9
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`US 7,241,988 B2
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`203
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`FIG.3
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`

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`U.S. Patent
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`Jul. 10, 2007
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`Sheet 4 of 9
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`US 7,241,988 B2
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`203
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`U.S. Patent
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`Jul. 10, 2007
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`Sheet 6 of 9
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`US 7,241,988 B2
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`203
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`

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`U.S. Patent
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`Jul. 10, 2007
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`Sheet 7 of 9
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`US 7,241,988 B2
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`U.S. Patent
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`Jul. 10, 2007
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`Sheet 9 of 9
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`US 7,241,988 B2
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`

`

`US 7,241,988 B2
`
`1
`SYSTEM AND METHOD OF SORTING
`MATERIALS USING HOLOGRAPHIC LASER
`STEERING
`
`The present invention claims priority from US. Provi-
`sional Patent Applications No. 60/399,386, filed Jul. 31,
`2002, and No. 60/435,541, filed Dec. 20, 2002, the contents
`of which are herein incorporated by reference.
`
`BACKGROUND OF THE INVENTION
`
`2
`
`islet purification is but one important problem
`Thus,
`requiring the highly selective sorting of human cells in a
`non-damaging, non-invasive way.
`Another problem that needs to be addressed is the puri-
`fication of normal cells from cancer cells in the bone marrow
`
`5
`
`of persons undergoing whole-body radiation treatment for
`cancer.
`Still another is the selection of stem cells for research into
`
`10
`
`the causes of, and therapies for, diseases such as Parkinson’s
`disease.
`
`The present invention relates to a system and method of
`sorting materials using laser steering, and in particular using
`holographic optical trapping.
`In United States industry, there is a large number of unmet
`sorting and separation needs involving material made up of
`particles or units smaller than 50 microns. These needs range
`across industries from particle sizing and sample preparation
`in the specialty chemicals and materials fields including
`manufacturing products of nanotechnology, to protein selec-
`tion and purification in the pharmaceutical and biotechnol-
`ogy industries. Other examples include cell sorting and
`selection, in the medical, diagnostic and agriculture sectors.
`The importance of these needs can be seen by exploring
`the annual expenditures in areas where specialized or partial
`solutions have been developed, as well as by estimating the
`market value of sorted/separated/purified output in areas
`where there is currently not even a partial solution. As an
`example of the former, the biotechnology and pharmaceu-
`tical industries annually spend a huge amount on equipment
`and supplies for protein purification.
`As an example of the latter, in the agricultural sector, there
`is currently no way to efliciently select
`the gender of
`offspring in farm animals; however, it is estimated that in the
`cattle area alone, value would be added by enabling such
`sperm selection as a part of the current artificial insemina-
`tion process widely used in the industry.
`Outside of the animal husbandry market, the purification
`process of islet cells from human pancreases is currently a
`large concern of medical scientists developing new treat-
`ment methods for Type I diabetes. Significant progress in
`islet transplantation methods has been made, but the puri-
`fication problem is one of the remaining stumbling blocks.
`Traditional methods for purifying islet cells are ineflicient
`and result in damage to the cells.
`lslet cell transplantation is important because, in the Type
`1 form of diabetes, the existing islet cells in the patient’s
`pancreas have become damaged and no longer produce the
`insulin which is required for human survival. The current
`treatment for Type I diabetes involves injection of insulin 1
`to 5 times per day. In spite of the treatment, the disease often
`leads to complications including blindness, blood flow prob-
`lems requiring amputation, renal failure, and death. Greater
`purity and reduced contaminants for islet cells used in
`transplantation is expected to reduce the occurrence of these
`complications.
`Of the approximately 1 million current sufferers of Type
`I diabetes in the United States, at least 50,000 sufferers per
`year would submit to islet cell transplantation if it were
`available. Upon large-scale acceptance of islet cell trans-
`plantation as an effective therapy, costs would be expected
`to jump substantially. The jump would be driven by the
`difliculty of using today’s treatment method (frequent inj ec-
`tions) and the severe consequences even when the current
`treatment is adequately administered.
`
`15
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`Yet another concern is developing new ways to automati-
`cally interrogate large numbers of human cells and select
`ones having characteristics not amenable to fluorescent
`tagging, which would enormously widen the scope and
`power of medical diagnoses.
`One conventional technique in manipulating microscopic
`objects is optical trapping. An accepted description of the
`effect of optical trapping is that tightly focused light, such as
`light focused by a high numerical aperture microscope lens,
`has a steep intensity gradient. Optical traps use the gradient
`forces of a beam of light to trap a particle based on its
`dielectric constant. “Particle” refers to a biological or other
`chemical material including, but not limited to, oligonucle-
`otides, polynucleotides, chemical compounds, proteins, lip-
`ids, polysaccharides,
`ligands, cells, antibodies, antigens,
`cellular organelles,
`lipids, blastomeres, aggregations of
`cells, microorganisms, peptides, cDNA, RNA and the like.
`To minimize its energy, a particle having a dielectric
`constant higher than the surrounding medium will move to
`the region of an optical trap where the electric field is the
`highest. Particles with at least a slight dielectric constant
`differential with their surroundings are sensitive to this
`gradient and are either attracted to or repelled from the point
`of highest light intensity, that is, to or from the light beam’s
`focal point. In constructing an optical trap, optical gradient
`forces from a single beam of light are employed to manipu-
`late the position of a dielectric particle immersed in a fluid
`medium with a refractive index smaller than that of the
`
`particle, but reflecting, absorbing and low dielectric constant
`particles may also be manipulated.
`The optical gradient force in an optical trap competes with
`radiation pressure which tends to displace the trapped par-
`ticle along the beam axis. An optical trap may be placed
`anywhere within the focal volume of an objective lens by
`appropriately selecting the input beam’s propagation direc-
`tion and degree of collimation. A collimated beam entering
`the back aperture of an objective lens comes to a focus in the
`center of the lens’ focal plane while another beam entering
`at an angle comes to a focus off-center. A slightly diverging
`beam focuses downstream of the focal plane while a con-
`verging beam focuses upstream. Multiple beams entering
`the input pupil of the lens simultaneously each form an
`optical trap in the focal volume at a location determined by
`its angle of incidence. The holographic optical trapping
`technique uses a phase modifying diffractive optical element
`to impose the phase pattern for multiple beams onto the
`wavefront of a single input beam, thereby transforming the
`single beam into multiple traps.
`Phase modulation of an input beam is preferred for
`creating optical traps because trapping relies on the inten-
`sities of beams and not on their relative phases. Amplitude
`modulations may divert light away from traps and diminish
`their effectiveness.
`
`When a particle is optically trapped, optical gradient
`forces exerted by the trap exceed other radiation pressures
`arising from scattering and absorption. For a Gaussian
`TEMOO input laser beam, this generally means that the beam
`
`

`

`US 7,241,988 B2
`
`3
`diameter should substantially coincide with the diameter of
`the entrance pupil. A preferred minimum numerical aperture
`to form a trap is about 0.9 to about 1.0.
`One difliculty in implementing optical trapping technol-
`ogy is that each trap to be generated generally requires its
`own focused beam of light. Many systems of interest require
`multiple optical traps, and several methods have been devel-
`oped to achieve multiple trap configurations. One existing
`method uses a single light beam that is redirected between
`multiple trap locations to “time-share” the beam between
`various traps. However, as the number of traps increases, the
`intervals during which each trap is in its “off” state may
`become long for particles to diffuse away from the trap
`location before the trap is re-energized. All these concerns
`have limited implementations of this method to less than
`about 10 traps per system.
`Another traditional method of creating multi-trap systems
`relies on simultaneously passing multiple beams of light
`through a single high numerical aperture lens. This is done
`by either using multiple lasers or by using one or more beam
`splitters in the beam of a single laser. One problem with this
`technique is that, as the number of traps increases,
`the
`optical system becomes progressively more and more com-
`plex. Because of these problems, the known implementa-
`tions of this method are limited to less than about 5 traps per
`system.
`In a third approach for achieving a multi-trap system, a
`diffractive optical element (DOE) (e.g., a phase shifting
`hologram utilizing either a transmission or a reflection
`geometry) is used to alter a single laser beam’s wavefront.
`This invention is disclosed in US. Pat. No. 6,055,106 to
`Grier et al. The wavefront is altered so that the downstream
`
`laser beam essentially becomes a large number of individual
`laser beams with relative positions and directions of travel
`fixed by the exact nature of the diffractive optical element.
`In effect, the Fourier transform of the DOE produces a set of
`intensity peaks each of which act as an individual trap or
`“tweezer.”
`
`Some implementations of the third approach have used a
`fixed transmission hologram to create between 16 and 400
`individual trapping centers.
`A fixed hologram has been used to demonstrate the
`principle of holographic optical trapping but using a liquid
`crystal grating as the hologram permitted ‘manufacture’ of a
`separate hologram for each new distribution of traps. The
`spatially varying phase modulation imposed on the trapping
`laser by the liquid crystal grating may be easily controlled in
`real
`time by a computer,
`thus permitting a variety of
`dynamic manipulations.
`Other types of traps that may be used to optically trap
`particles include, but are not limited to, optical vortices,
`optical bottles, optical rotators and light cages. An optical
`vortex produces a gradient surrounding an area of zero
`electric field which is useful to manipulate particles with
`dielectric constants lower than the surrounding medium or
`which are reflective, or other types of particles which are
`repelled by an optical trap. To minimize its energy, such a
`particle will move to the region where the electric field is the
`lowest, namely the zero electric field area at the focal point
`of an appropriately shaped laser beam. The optical vortex
`provides an area of zero electric field much like the hole in
`a doughnut (toroid). The optical gradient is radial with the
`highest electric field at the circumference of the doughnut.
`The optical vortex detains a small particle within the hole of
`the doughnut. The detention is accomplished by slipping the
`vortex over the small particle along the line of zero electric
`field.
`
`10
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`The optical bottle differs from an optical vortex in that it
`has a zero electric field only at the focus and a non-zero
`electric field in all other directions surrounding the focus, at
`an end of the vortex. An optical bottle may be useful in
`trapping atoms and nanoclusters which may be too small or
`too absorptive to trap with an optical vortex or optical
`tweezers. (See J. Arlt and M. J. Padgett. “Generation of a
`beam with a dark focus surrounded by regions of higher
`intensity: The optical bottle beam,” Opt. Lett. 25, 1917193,
`2000.)
`The light cage (US. Pat. No. 5,939,716) is loosely, a
`macroscopic cousin of the optical vortex. A light cage forms
`a time-averaged ring of optical traps to surround a particle
`too large or reflective to be trapped with dielectric constants
`lower than the surrounding medium.
`When the laser beam is directed through or reflected from
`the phase patterning optical element, the phase patterning
`optical element produces a plurality of beamlets having an
`altered phase profile. Depending on the number and type of
`optical traps desired, the alteration may include diffraction,
`wavefront shaping, phase shifting, steering, diverging and
`converging. Based upon the phase profile chosen, the phase
`patterning optical element may be used to generate optical
`traps in the form of optical traps, optical vortices, optical
`bottles, optical rotators, light cages, and combinations of
`two or more of these forms.
`
`With respect to the manipulation of materials, tweezing of
`viruses and bacteria has been demonstrated in addition to
`
`tweezing of dielectric spheres. In addition to prokaryotes
`and viruses, a large variety of protists such as Telrahymena
`lhermophila has been successfully tweezed. Furthermore,
`both somatic cells such as eukocytes and epithelial cheek
`cells, and germ line cells such as spermatozoa have been
`trapped and manipulated.
`Researchers have sought indirect methods for manipulat-
`ing cells, such as tagging the cells with diamond micro-
`particles and then tweezing the diamond particles. Cell
`manipulations have included cell orientation for micro-
`scopic analysis as well as stretching cells. Tissue cells have
`also been arranged with tweezers in vitro in the same spatial
`distribution as in vivo.
`
`In addition to the cells themselves, optical tweezers have
`been used to manipulate cellular organelles, such as vesicles
`transported along microtubules, chromosomes, or globular
`DNA. Objects have also been inserted into cells using
`optical tweezers.
`A variety of sorting processes for biological purposes is
`also possible with optical tweezers. Cell sorting using tra-
`ditional optical trapping for assays and chromosome collec-
`tion and sorting to create libraries have already been dem-
`onstrated. Cell assays for drug screening have also been
`developed.
`Accordingly, as an example of new types of sorting using
`laser steered optical traps, a method of cell sorting using a
`technique which isolates valuable cells from other cells,
`tissues, and contaminants is needed. Further, a way of
`achieving a unique contribution of optical trapping to the
`major industrial needs of (cell) sorting and purification is
`required. Still further, there is a need to separate sperm cells
`in the animal husbandry market.
`
`SUMMARY OF THE INVENTION
`
`The present invention relates to a system and method of
`sorting materials using laser steering, and in particular using
`holographic optical trapping.
`
`

`

`US 7,241,988 B2
`
`5
`In one embodiment consistent with the present invention,
`optical trapping, which is a technology which has been used
`as a tool for manipulating microscopic objects, is used. An
`accepted description of the effect is that tightly focused light,
`such as light focused by a high numerical aperture micro-
`scope lens, has a steep intensity gradient. Optical traps use
`the gradient forces of a beam of light to trap a particles based
`on its dielectric constant To minimize its energy, a particle
`having a dielectric constant higher than the surrounding
`medium will move to the region of an optical trap where the
`electric field is the highest.
`invention is used to
`Optical
`trapping of the present
`address cell sorting and purification in several ways. For
`example, the forces exerted by optical traps on a material are
`sensitive to the exact distribution of the dielectric constant in
`
`that materialithe optical force therefore depends on the
`composition and shape of the object.
`Further, other forces on the object are sensitive to the
`hydrodynamic interaction between the object and the sur-
`rounding fluidicontrol of the fluid flow probes material
`shape, size and such features as surface rugosity.
`Still further,
`localizing an object at a known position
`allows additional methods of automated interrogation such
`as high speed imaging and particle-specific scattering mea-
`surements.
`
`In one embodiment consistent with the present invention,
`in achieving a multi-trap system, a diffractive optical ele-
`ment (DOE, i.e., a phase shifting hologram utilizing either a
`transmission or a reflection geometry) is used to alter a
`single laser beam’s wavefront. The wavefront is altered so
`that the downstream laser beam essentially becomes a large
`number of individual laser beams with relative positions and
`directions of travel fixed by the exact nature of the diffrac-
`tive optical element.
`The present invention provides optical trapping by focus-
`ing a laser beam with a lens to create an optical trap wherein
`the lens has a numerical aperture less than 0.9, and prefer-
`ably decreases until it is most preferably less than 0.1.
`Sorting using holographic laser steering involves estab-
`lishing classes of identification for objects to be sorted,
`introducing an object to be sorted into a sorting area, and
`manipulating the object with a steered laser according to its
`identity class. The manipulation may be holding, moving,
`rotating, tagging or damaging the object in a way which
`differs based upon its identity class. Thus,
`the present
`invention provides a way of implementing a parallel
`approach to cell sorting using holographic optical trapping.
`In one embodiment of the present invention, spectroscopy
`of a sample of biological material may be accomplished with
`an imaging illumination source suitable for either inelastic
`spectroscopy or polarized light back scattering, the former
`being useful for assessing chemical identity, and the latter
`being suited for measuring dimensions of internal structures
`such as the nucleus size. Using such spectroscopic methods,
`in some embodiments, cells are interrogated. The spectrum
`of those cells which had positive results (i.e., those cells
`which reacted with or bonded with a label) may be obtained
`by using this imaging illumination.
`A computer program may analyze the spectral data to
`identify the desired targets (i.e., cells bearing either an X or
`Y chromosome, or a suspected cancerous, pre-cancerous
`and/or non-cancerous cell types, etc.), then may apply the
`information to direct the phase patterning optical element
`(i.e., optical traps) to segregate or contain those desired or
`selected targets (i.e., cell types). The contained cells may be
`identified based on the reaction or binding of the contained
`cells with chemicals, or by using the natural fluorescence of
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`the object, or the fluorescence of a substance associated with
`the object, as an identity tag or background tag. Upon
`completion of the assay, selection may be made, via com-
`puter and/or operator, of which cells to discard and which to
`collect.
`
`Manipulation of cells in general, is made safer by having
`multiple beams available. Like a bed of nails, multiple
`tweezers ensure that less power is introduced at any par-
`ticular spot in the cell. This eliminates hot spots and reduces
`the risk of damage. Any destructive two-photon processes
`benefit greatly since the absorption is proportional to the
`square of the laser power. Just adding a second tweezer
`decreases two-photon absorption in a particular spot by a
`factor of four. Large cells like Telrahymena involves a large
`amount of laser power for effective trapping. Putting the
`power into a single trap may cause immediate damage to the
`cell.
`
`is greatly
`The manipulation of even just a single cell
`enhanced by utilizing holographic optical
`trapping,
`for
`example. A single epithelial cheek cell may be manipulated
`by a line of tweezers, which lift the cell along the perimeter
`on one side. The resulting rotation allows a 360 degree view
`of the cell. In addition to the advantage for viewing of
`biological samples, there also exists the ability to orient
`samples stably, which has clear benefit for studies such as
`scattering experiments which have a strong dependence on
`orientation of the sample.
`Sorting with a wide field of view has many advantages
`such as higher throughput. However, standard tweezing in a
`WFOV may fails du to excessive radiation pressure. Tweez-
`ing with a wide field of view using holographic optical
`trapping may permit the ability to form exotic modes of light
`which greatly reduce the radiation pressure of the light
`beam. Vortex traps, for example, have a dark center because
`the varying phases of light cancel in the center of the trap.
`This dark center means most of the rays of light which travel
`down the center of the beam no longer exist. It is exactly
`these beams which harbor most of the radiation pressure of
`the light, so their removal greatly mitigates the difliculty in
`axial trapping. Other modes, e.g., donut modes, have the
`same advantage.
`In one embodiment consistent with the present invention,
`the method and system lends itself to a semi-automated or
`automated process for tracking the movement and contents
`of each optical trap. In one embodiment consistent with the
`present
`invention, movement may be monitored via an
`optical data stream which can be viewed, or converted to a
`video signal, monitored, or analyzed by visual inspection of
`an operator, spectroscopically, and/or by video monitoring.
`The optical data stream may also be processed by a photo-
`detector to monitor intensity, or any suitable device to
`convert the optical data stream to a digital data stream
`adapted for use by a computer and program. The computer
`program controls the selection of cells and the generation of
`optical traps.
`In other embodiments consistent with the present inven-
`tion, the movement of cells is tracked based on predeter-
`mined movement of each optical trap caused by encoding
`the phase patterning optical element. Additionally, in some
`embodiments, a computer program maintains a record of
`each cell contained in each optical trap.
`In one embodiment consistent with the present invention,
`cell sorting of X and Y sperm for animal husbandry is
`performed.
`the ability to change the
`In the beef cattle industry,
`male/female ratio of the offspring from the current 50%: 50%
`mix to an 85%:15% mix would dramatically increase the
`
`

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`US 7,241,988 B2
`
`7
`value of the annual offspring. A similar, though smaller,
`increase in value would occur in the dairy industry.
`In one embodiment consistent with the present invention,
`a method of sorting objects includes the steps of introducing
`the objects into an input channel at a predetermined flow
`rate; funneling the objects using a beam steering apparatus;
`evaluating the objects to determine which meet a predeter-
`mined criteria; and sorting the objects which meet said
`criteria from objects which do not meet said criteria.
`In another embodiment consistent with the present inven-
`tion, a method of sorting objects includes the steps of
`distributing the objects over a surface of a structure; and
`evaluating the objects in said structure according to a
`predetermined criteria using a beam steering apparatus.
`In yet another embodiment consistent with the present
`invention, a method of sorting objects includes the steps of
`distributing the objects in a gel; detecting the objects which
`meet a predetermined criteria; and sorting the objects which
`meet said criteria from objects which do not meet said
`criteria.
`
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes a plu-
`rality of optical
`traps formed using an optical
`trapping
`apparatus; an input channel
`into which the objects are
`introduced at a predetermined flow rate; and at least one
`output channel; wherein the objects are sorted according to
`predetermined criteria using said optical traps in a sorting
`region prior to entering said output channel.
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes a beam
`steering apparatus; and a structure having a surface on which
`the objects are distributed; wherein the objects are sorted
`using said bean steering apparatus, according to whether the
`objects meet predetermined criteria.
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes means
`for introducing the objects into an input channel at a
`predetermined flow rate; means for funneling the objects;
`means for evaluating the objects to determine which objects
`meet predetermined criteria; and means for sorting the
`objects which meet said criteria from objects which do not
`meet said criteria.
`
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes means
`for distributing the objects over a surface of a structure; and
`means for evaluating the objects in said structure according
`to predetermined criteria using a beam steering apparatus.
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes means
`for distributing the objects in a gel; means for detecting the
`objects which meet a predetermined criteria; and means for
`sorting the objects which meet said criteria from objects
`which do not meet said criteria.
`
`In yet another embodiment consistent with the present
`invention, a method of sorting objects includes the steps of
`accessing an object using an optical trap; examining said
`object to determine its identity; and sorting said identified
`object according to predetermined criteria.
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes means
`for accessing an object using an optical trap; means for
`examining said object to determine its identity; and means
`for sorting said identified object according to predetermined
`criteria.
`
`In yet another embodiment consistent with the present
`invention, an apparatus for sorting objects includes a beam
`steering apparatus including: a laser which provides a laser
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`beam for illumination; a diffractive optical element which
`diffracts said beam into a plurality of beamlets; and an
`objective lens which converges the beamlet, thereby pro-
`ducing optical gradient conditions resulting in an optical
`data stream to form an optical trap; and a sample chamber
`into which the objects are introduced, trapped and sorted.
`In yet another embodiment consistent with the present
`invention, a method of manipulating objects includes intro-
`ducing the objects into an evaluation system; evaluating the
`objects according to a predetermined criteria using a beam
`steering apparatus; and manipulating the objects according
`to said predetermined criteria using said beam steering
`apparatus.
`In yet another embodiment consistent with the present
`invention, a method of destroying objects includes accessing
`an object using a beam steering apparatus; examining said
`object to determine its identity; sorting said identified object
`according to predetermined criteria; and destroying said
`identified object when said object meets said predetermined
`criteria.
`
`Finally, in yet another embodiment consistent with the
`present
`invention, an apparatus
`for destroying objects
`includes means for accessing an object using a beam steer-
`ing apparatus; means for examining said object to determine
`its identity; means for sorting said identified object accord-
`ing to predetermined criteria; and means for destroying said
`identified object when said object meets said predetermined
`criteria.
`
`There has thus been outlined, rather broadly, some fea-
`tures consistent with the present invention in order that the
`detailed description thereof that follows may be better
`understood, and in order that the present contribution to the
`art may be better appreciated. There are, of course, addi-
`tional features consistent with the present invention that will
`be described below and which will form the subject matter
`of the claims appended hereto.
`In this respect, before explaining at least one embodiment
`consistent with the present invention in detail, it is to be
`understood that