Abstract

We designed, constructed, and tested a single-beam optical trapping instrument employing twin electro-optic deflectors (EODs) to steer the trap in the specimen plane. Compared with traditional instruments based on acousto-optic deflectors (AODs), EOD-based traps offer a significant improvement in light throughput and a reduction in deflection-angle (pointing) errors. These attributes impart improved force and position resolution, making EOD-based traps a promising alternative for high-precision nanomechanical measurements of biomaterials.

© 2008 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |

  1. K. C. Neuman and S. M. Block, Rev. Sci. Instrum. 75, 2787 (2004).
    [CrossRef]
  2. R. M. Simmons, J. T. Finer, S. Chu, and J. A. Spudich, Biophys. J. 70, 1813 (1996).
    [CrossRef] [PubMed]
  3. K. Visscher and S. M. Block, Methods Enzymol. 298, 460 (1998).
    [CrossRef] [PubMed]
  4. K. Visscher, M. J. Schnitzer, and S. M. Block, Nature 400, 184 (1999).
    [CrossRef] [PubMed]
  5. M. J. Lang, C. L. Asbury, J. W. Shaevitz, and S. M. Block, Biophys. J. 83, 491 (2002).
    [CrossRef] [PubMed]
  6. S. M. Block, C. L. Asbury, J. W. Shaevitz, and M. J. Lang, Proc. Natl. Acad. Sci. USA 100, 2351 (2003).
    [CrossRef] [PubMed]
  7. C. Veigel, J. E. Molloy, S. Schmitz, and J. Kendrick-Jones, Nat. Cell Biol. 5, 980 (2003).
    [CrossRef] [PubMed]
  8. M. T. Woodside, P. C. Anthony, W. M. Behnke-Parks, K. Larizadeh, D. Hershlag, and S. M. Block, Science 314, 1001 (2006).
    [CrossRef] [PubMed]
  9. C. L. Asbury, A. N. Fehr, and S. M. Block, Science 302, 2130 (2003).
    [CrossRef] [PubMed]
  10. J. P. Rickgauer, D. N. Fuller, and D. E. Smith, Biophys. J. 91, 4253 (2006).
    [CrossRef] [PubMed]

2006 (2)

M. T. Woodside, P. C. Anthony, W. M. Behnke-Parks, K. Larizadeh, D. Hershlag, and S. M. Block, Science 314, 1001 (2006).
[CrossRef] [PubMed]

J. P. Rickgauer, D. N. Fuller, and D. E. Smith, Biophys. J. 91, 4253 (2006).
[CrossRef] [PubMed]

2004 (1)

K. C. Neuman and S. M. Block, Rev. Sci. Instrum. 75, 2787 (2004).
[CrossRef]

2003 (3)

C. L. Asbury, A. N. Fehr, and S. M. Block, Science 302, 2130 (2003).
[CrossRef] [PubMed]

S. M. Block, C. L. Asbury, J. W. Shaevitz, and M. J. Lang, Proc. Natl. Acad. Sci. USA 100, 2351 (2003).
[CrossRef] [PubMed]

C. Veigel, J. E. Molloy, S. Schmitz, and J. Kendrick-Jones, Nat. Cell Biol. 5, 980 (2003).
[CrossRef] [PubMed]

2002 (1)

M. J. Lang, C. L. Asbury, J. W. Shaevitz, and S. M. Block, Biophys. J. 83, 491 (2002).
[CrossRef] [PubMed]

1999 (1)

K. Visscher, M. J. Schnitzer, and S. M. Block, Nature 400, 184 (1999).
[CrossRef] [PubMed]

1998 (1)

K. Visscher and S. M. Block, Methods Enzymol. 298, 460 (1998).
[CrossRef] [PubMed]

1996 (1)

R. M. Simmons, J. T. Finer, S. Chu, and J. A. Spudich, Biophys. J. 70, 1813 (1996).
[CrossRef] [PubMed]

Biophys. J. (3)

R. M. Simmons, J. T. Finer, S. Chu, and J. A. Spudich, Biophys. J. 70, 1813 (1996).
[CrossRef] [PubMed]

M. J. Lang, C. L. Asbury, J. W. Shaevitz, and S. M. Block, Biophys. J. 83, 491 (2002).
[CrossRef] [PubMed]

J. P. Rickgauer, D. N. Fuller, and D. E. Smith, Biophys. J. 91, 4253 (2006).
[CrossRef] [PubMed]

Methods Enzymol. (1)

K. Visscher and S. M. Block, Methods Enzymol. 298, 460 (1998).
[CrossRef] [PubMed]

Nat. Cell Biol. (1)

C. Veigel, J. E. Molloy, S. Schmitz, and J. Kendrick-Jones, Nat. Cell Biol. 5, 980 (2003).
[CrossRef] [PubMed]

Nature (1)

K. Visscher, M. J. Schnitzer, and S. M. Block, Nature 400, 184 (1999).
[CrossRef] [PubMed]

Proc. Natl. Acad. Sci. USA (1)

S. M. Block, C. L. Asbury, J. W. Shaevitz, and M. J. Lang, Proc. Natl. Acad. Sci. USA 100, 2351 (2003).
[CrossRef] [PubMed]

Rev. Sci. Instrum. (1)

K. C. Neuman and S. M. Block, Rev. Sci. Instrum. 75, 2787 (2004).
[CrossRef]

Science (2)

M. T. Woodside, P. C. Anthony, W. M. Behnke-Parks, K. Larizadeh, D. Hershlag, and S. M. Block, Science 314, 1001 (2006).
[CrossRef] [PubMed]

C. L. Asbury, A. N. Fehr, and S. M. Block, Science 302, 2130 (2003).
[CrossRef] [PubMed]

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)

Fig. 1
Fig. 1

Schematic layout for the EOD-based optical trap. Dichroic mirror (DM) DM1 combines trapping (black lines, red online) and detection (thin gray lines, orange online) beams. DM2 directs both beams through a Wollaston prism (W) into a high-NA (1.40) microscope objective (O); an optical trap is formed in the specimen plane (SP). A series of lens pairs placed in both laser paths image the objective back focal plane onto the steering lenses and EODs (conjugate planes are indicated by black hatching, blue online). An NA-matched condenser lens (C) collects forward-scattered laser light. DM3 reflects the trapping and detection beams while passing brightfield illumination light from an arc lamp (thick gray line, green online). A short-pass filter (F) blocks the trapping laser, and a duolateral position-sensitive detector (PSD) collects the detection light. S, shutter; BB, beam block; PBS, polarizing beam splitter; ISO, optical isolator; HWP, half-wave plate; MHWP, motorized half-wave plate.

Fig. 2
Fig. 2

Transmittance as a function of trap position for orthogonal deflectors. The EOD-based optical trap (left) displayed 81 % transmittance with < 0.5 % variation for displacements of ± 0.76 μ m in the specimen plane (corresponding to the full working range), whereas the AOD-based optical trap (right) displayed 55 % transmittance with > 20 % variation for displacements of ± 2.5 μ m ( ± 2.5 MHz around center frequencies of 21.8 MHz in the x dimension, 30 MHz in the y dimension).

Fig. 3
Fig. 3

Linearity of EOD and AOD response. (a) Particle trapped 500 nm above the coverslip surface was moved in an eight-armed star pattern by EOD- (left) or AOD-driven (right) deflections of the trapping beam. Data were sampled at 50 kHz and Bessel filtered at 25 kHz ; 1000 samples were averaged at each of 200 positions per arm. The x and y trap stiffnesses ( κ ) were determined by averaging values estimated by two methods: (1) the mean-squared displacement and (2) the corner frequency of the Lorentzian power spectrum [1]. For the EOD-based device, κ x = 0.16 pN nm 1 and κ y = 0.20 pN nm 1 ; for the AOD-based device, κ x = 0.27 pN nm 1 and κ y = 0.16 pN nm 1 . (b) EOD-driven beads accurately followed the targeted trajectory, as seen in an expanded view (left). AOD-driven particles (right) displayed characteristic wiggles (see text). (c) Histograms of the displacement data in panel (b).

Fig. 4
Fig. 4

Experimental record showing the displacement of a single kinesin molecule bound to a bead (black curve) and the corresponding trap position (gray curve, red online) versus time under force-clamped conditions [6], showing steps of 8.2 nm (dashed gray lines). A recombinant derivative of D. melanogaster kinesin (DmK612) was used in this assay [9], with [ ATP ] = 100 μ M , trap stiffness = 0.07 pN nm 1 , and hindering force = 4.9 pN . Inset, diagram showing the experimental geometry (not to scale), where a single kinesin motor, bound to a bead held in the optical trap, steps along a microtubule attached to the coverslip.

Metrics