The detailed design of a robust and inexpensive optical trap system is presented. The system features high-sensitivity back focal plane position detection, mechanically controlled specimen stage movement, and fluorescence imaging to provide broad experimental applications. Three educational experimental modules are described to cover basic concepts in optical trapping and biophysics at a level appropriate for undergraduate students.
REFERENCES
1.
A.
Ashkin
, “Acceleration and trapping of particles by radiation pressure
,” Phys. Rev. Lett.
24
(4
), 156
–159
(1970
).2.
M. J.
Lang
and S. M.
Block
, “Resource Letter: LBOT-1: Laser-based optical tweezers
,” Am. J. Phys.
71
(3
), 201
–215
(2003
).3.
M. J.
Lang
, P. M.
Fordyce
, A. M.
Engh
, K. C.
Neuman
, and S. M.
Block
, “Simultaneous, coincident optical trapping and single-molecule fluorescence
,” Nat. Methods
1
(2
), 133
–139
(2004
).4.
K.
Visscher
, M. J.
Schnitzer
, and S. M.
Block
, “Single kinesin molecules studied with a molecular force clamp
,” Nature (London)
400
, 184
–189
(1999
).5.
A.
Ishijima
, H.
Kojima
, T.
Funatsu
, M.
Tokunaga
, H.
Higuchi
, H.
Tanaka
, and T.
Yanagida
, “Simultaneous observation of individual ATPase and mechanical events by a single myosin molecule during interaction with actin
,” Cell
92
(2
), 161
–171
(1998
).6.
C. G.
Galbraith
and M. P.
Sheetz
, “Keratocytes pull with similar forces on their dorsal and ventral surfaces
,” J. Cell Biol.
147
(6
), 1313
–1324
(1999
).7.
S. P.
Smith
, S. R.
Bhalotra
, A. L.
Brody
, B. L.
Brown
, E. K.
Boyda
, and M.
Prentiss
, “Inexpensive optical tweezers for undergraduate laboratories
,” Am. J. Phys.
67
(1
), 26
–35
(1999
).8.
R.
Pastel
, A.
Struthers
, R.
Ringle
, J.
Rogers
, C.
Rohde
, and P.
Geiser
, “Laser trapping of microscopic particles for undergraduate experiments
,” Am. J. Phys.
68
(11
), 993
–1001
(2000
).9.
D. N.
Moothoo
, J.
Arlt
, R. S.
Conroy
, F.
Akerboom
, A.
Voit
, and K.
Dholakia
, “Beth’s experiment using optical tweezers
,” Am. J. Phys.
69
(3
), 271
–276
(2001
).10.
J.
Bechhoefer
and S.
Wilson
, “Faster, cheaper, safer optical tweezers for the undergraduate laboratory
,” Am. J. Phys.
70
(4
), 393
–400
(2002
).11.
K. C.
Neuman
, E. H.
Chadd
, F. G.
Liou
, K.
Bergman
, and S. M.
Block
, “Characterization of photodamage to Escherichia coli in optical traps
,” Biophys. J.
77
(5
), 2856
–2863
(1999
).13.
K.
Svoboda
and S. M.
Block
, “Biological applications of optical forces
,” Annu. Rev. Biophys. Biomol. Struct.
23
, 247
–285
(1994
).14.
M. P.
Sheetz
, “Laser tweezers in cell biology
,” Methods Cell Biol.
55
, 111
–112
(1998
).15.
M. J.
Lang
, C. L.
Asbury
, J. W.
Shaevitz
, and S. M.
Block
, “An automated two-dimensional optical force clamp for single molecule studies
,” Biophys. J.
83
(1
), 491
–501
(2002
).16.
M. W.
Allersma
, F.
Gittes
, M. J.
deCastro
, R. J.
Stewart
, and C. F.
Schmidt
, “Two-dimensional tracking of ncd motility by back focal plane interferometry
,” Biophys. J.
74
(2
), 1074
–1085
(1998
).17.
K. M.
Addas
, C. F.
Schmidt
, and J. X.
Tang
, “Microrheology of solutions of semiflexible biopolymer filaments using laser tweezers interferometry
,” Phys. Rev. E
70
, 021503
–1
(2004
).18.
K.
Berg-Sorensen
and H.
Flyvbjerg
, “Power spectrum analysis for optical tweezers
,” Rev. Sci. Instrum.
75
(3
), 594
–612
(2004
).19.
K. C.
Neuman
and S. M.
Block
, “Optical trapping
,” Rev. Sci. Instrum.
75
(9
), 2787
–2809
(2004
).20.
J. T.
Finer
, R. M.
Simmons
, and J. A.
Spudich
, “Single Myosin molecule mechanics: Piconewton forces and nanometer steps
,” Nature (London)
368
(6467
), 113
–119
(1994
).21.
B. E.
Scharf
, K. A.
Fahrner
, L.
Turner
, and H. C.
Berg
, “Control of direction of flagellar rotation in bacterial chemotaxis
,” Proc. Natl. Acad. Sci. U.S.A.
95
(1
), 201
–206
(1998
).22.
R. M.
Berry
and H. C.
Berg
, “Torque generated by the flagellar motor of Escherichia coli while driven backward
,” Biophys. J.
76
(1
), 580
–587
(1999
).23.
24.
Gift of Dr. Karen Fahrner,
Harvard University
.25.
K.
Barker
, At the Bench: A Laboratory Navigator
(Cold Spring Harbor Laboratory
, Woodbury, NY
, 1998
).26.
M.
Silverman
and M.
Simon
, “Flagellar rotation and the mechanism of bacterial motility
,” Nature (London)
249
, 73
–74
(1974
).27.
M. D.
Wang
, M. J.
Schnitzer
, H.
Yin
, R.
Landick
, J.
Gelles
, and S. M.
Block
, “Force and velocity measured for single molecules of RNA polymerase
,” Science
282
(5390
), 902
–907
(1998
).28.
H.
Miyata
, H.
Yoshikawa
, H.
Hakozaki
, N.
Suzuki
, T.
Furuno
, A.
Ikegami
, K.
Kinosita
, Jr., T.
Nishizaka
, and S.
Ishiwata
, “Mechanical measurements of single actomyosin motor force
,” Biophys. J.
68
(4 Suppl), 286S
–289S
(1995
).29.
J. F.
Marko
and E. D.
Siggia
, “Stretching DNA
,” Macromolecules
28
(26
), 8759
–8770
(1995
).30.
M. D.
Wang
, H.
Yin
, R.
Landick
, J.
Gelles
, and S. M.
Block
, “Stretching DNA with optical tweezers
,” Biophys. J.
72
(3
), 1335
–1346
(1997
).31.
P.
Nelson
, Biological Physics: Energy, Information, Life
(W. Freeman
, New York
, 2004
).32.
33.
F. M.
Ausubel
, R.
Brent
, R. E.
Kingston
, D. D.
Moore
, J. G.
Seidman
, J. A.
Smith
, and K.
Struhl
, Short Protocols in Molecular Biology
, 5th ed. (Wiley
, New York
, 2002
).34.
E.
Berliner
, H. K.
Mahtani
, S.
Karki
, L. F.
Chu
, J. E.
Cronan
, Jr., and J.
Gelles
, “Microtubule movement by a biotinated kinesin bound to streptavidin-coated surface
,” J. Biol. Chem.
269
(11
), 8610
–8615
(1994
).35.
J. M.
Khosrofian
and B. A.
Garetz
, “Measurement of a Gaussian laser-beam diameter through the direct inversion of knife-edge data
,” Appl. Opt.
22
(21
), 3406
–3410
(1983
).© 2007 American Association of Physics Teachers.
2007
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