Optical Tweezers - The Nanobiotechnology - page 456

for.integrating.with.other.technologies..These.advantages.make.it.a.powerful.tool.in.life.
science.studies.including.biomechanics.and.cell.biology..Many.successful.examples.have.
been.reported.and.only.a.few.of.them.are.presented.here..Details.of.optical.tweezers.and.
their.applications.can.be.found.from.the.listed.references.
One. important. application. branch. of. optical. tweezers. lies. in. the. trapping. and.
manipulation.of.living.systems,.such.as.cellular.components.and.cells.themselves..In.these.
biological.systems,.cell.in.particular,.an.intrinsic.problem.associated.with.optical.tweezers.
is.their.photochemical-.or.thermal-induced.effects..The.highly.focused.laser.often.leads.to.
the.deformation,.damage,.or.even.death.of.cells..Appropriate.choices.on.the.surrounding.
medium. might. help. reduce. photodamage. to. an. acceptable. level,. but. it. remains. a. great.
challenge..Further.improvements.may.target.the.lexibility.of.local,.selective,.and.multiple-
site. trapping. to. reduce. its. negative. impact. on. cell. metabolism. and. viability.. These. new.
strategies. may. offer. several. advantages:. (1). to. disperse. and. dilute. optical. energy,. the.
generated.radiation.stress,.or.photodamage.to.multiple.tiny.portions.of.a.cell;.(2).to.offer.
options.for.the.trap.sites.or.locations.and.nonuniformly.trap,.based.on.the.heterogeneity.
on.mass,.permeability,.and.other.properties.across.the.cell..The.use.of.computer-controlled.
holograms. indicates. a. clear. movement. of. current. optical. tweezers. instruments. toward.
such. capability.. But. more. progress. is. urgently. needed. to. attain. truly. independent,. 3D.
manipulation. with. nanometer. resolution,. low. disturbance,. and. multiple. trap. lexibility..
Delectors.with.faster.operating.speeds.and.large.effective.trapping.areas.as.well.as.laser.
sources. of. simultaneous. multiple. beams. of. various. wavelengths. are. just. a. few. of. many.
features.desired.in.future.optical.tweezers.apparatuses.
The. exploration. of. the. new. applications. of. optical. tweezers. should. continue. to. focus.
on. its. integration. with. other. technologies. or. processes.. Technologies,. like. confocal.
microscopy,.Raman.spectroscopy,.patch.clamping,.and.microluidics,.have.been.combined.
with.optical.tweezers.for.better.monitoring.or.measuring.of.many.biological.phenomena..
The. recent. emerging. imaging. and. single. molecular. technologies,. such. as. luorescence.
resonance. energy. transfer. (or. FRET),. might. also. be. combined. to. further. increase. the.
detecting.and.measuring.resolution..With.its.excellence.in.the.creation.of.model.systems.
for.many.biological.systems,.optical.tweezers.should.continue.to.be.used.in.various.life.
science. ields,. such. as. pharmaceutics,. regenerative. medicine,. and. tissue. engineering,. to.
better.reveal.or.reexamine.their.mechanisms.and.signal.paths.
References
Abbondanzieri,. E.. A.,. Greenleaf,. W.. J.,. Shaevitz,. J.. W.,. Landick,. R.. &. Block,. S.. M.. (2005). Direct.
observation.of.base-pair.stepping.by.RNA.polymerase.. Nature ,.438,.460-465.
Akselrod,.G..M.,.Timp,.W.,.Mirsaidov,.U.,.Zhao,.Q.,.Li,.C.,.Timp,.K.,.Matsudaira,.P.,.and.Timp,.G..
(2006).Laser-guided.assembly.of.heterotypic.three-.dimensional.living.cell.microarrays.. Biophys
J ,.91,.3465-3473.
Ashkin,.A..(2007). Optical Trapping and Manipulation of Neutral Particles Using Lasers: A Reprint Volume
with Commentaries ..World.Scientiic.Publishing.Company,.River.Edge,.NJ.
Ashkin,.A.. and. Dziedzic,. J.. M.. (1987). Optical. trapping. and. manipulation. of. viruses. and. bacteria..
Science ,.235,.1517-1520.
Ashkin,.A.,.Dziedzic,.J..M.,.Bjorkholm,.J..E.,.and.Chu,.S..(1986).Observation.of.a.single-beam.gradient.
force.optical.trap.for.dielectric.particles.. Opt Lett ,.11,.288-290.
Bockelmann,.U.,.Thomen,.P.,.Essevaz.Roulet,.B.,.Viasnoff,.V.,.and.Heslot,.F..(2002).Unzipping.DNA.
with.optical.tweezers:.High.sequence.sensitivity.and.force.lips.. Biophys J ,.82(3):1537-1553.