Abstract

In an optical trap, micron-sized dielectric particles are held by a tightly focused laser beam. The optical force on the particle is composed of an attractive gradient force and a destabilizing scattering force. We hypothesized that using anti-reflection-coated microspheres would reduce scattering and lead to stronger trapping. We found that homogeneous silica and polystyrene microspheres had a sharp maximum trap stiffness at a diameter of around 800 nm—the trapping laser wavelength in water—and that a silica coating on a polystyrene microsphere was a substantial improvement for larger diameters. In addition, we noticed that homogeneous spheres of a correct size demonstrated anti-reflective properties. Our results quantitatively agreed with Mie scattering calculations and serve as a proof of principle. We used a DNA stretching experiment to confirm the large linear range in detection and force of the coated microspheres and performed a high-force motor protein assay. These measurements show that the surfaces of the coated microspheres are compatible with biophysical assays.

© 2008 Optical Society of America

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    [CrossRef] [PubMed]
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2008 (3)

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

Y. Hu, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Antireflection coating for improved optical trapping," J. Appl. Phys. 103, 093119 (2008).
[CrossRef]

C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, and C. Bechinger, "Direct measurement of critical Casimir forces," Nature 451, 172-175 (2008).
[CrossRef] [PubMed]

2007 (6)

V. Bormuth, J. Howard, and E. Schaffer, "LED illumination for video-enhanced DIC imaging of single microtubules," J. Microsc. 226, 1-5 (2007).
[CrossRef] [PubMed]

S. N. S. Reihani and L. B. Oddershede, "Optimizing immersion media refractive index improves optical trapping by compensating spherical aberrations," Opt. Lett. 32, 1998-2000 (2007).
[CrossRef] [PubMed]

C. Leduc, F. Ruhnow, J. Howard, and S. Diez, "Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors," Proc. Natl. Acad. Sci. U. S. A. 104, 10847-10852 (2007).
[CrossRef] [PubMed]

M. C. Noom, B. van den Broek, J. van Mameren, and G. J. L. Wuite, "Visualizing single DNA-bound proteins using DNA as a scanning probe," Nat. Method 4, 1031-1036 (2007).
[CrossRef]

E. Schaffer, S. F. Nørrelykke, and J. Howard, "Surface forces and drag coefficients of microspheres near a plane surface measured with optical tweezers," Langmuir 23, 3654-3665 (2007).
[CrossRef] [PubMed]

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
[CrossRef]

2006 (5)

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

G. Knoner, S. Parkin, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Measurement of the index of refraction of single microparticles," Phys. Rev. Lett. 97, 157402 (2006).
[CrossRef] [PubMed]

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli, and P. A. M. Neto, "Characterization of objective transmittance for optical tweezers," Appl. Opt. 45, 4263-4269 (2006).
[CrossRef] [PubMed]

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

S. F. Tolic-Nørrelykke, E. Schaffer, J. Howard, F. S. Pavone, F. Julicher, and H. Flyvbjerg, "Calibration of optical tweezers with positional detection in the back focal plane," Rev. Sci. Instrum. 77, 103101 (2006).
[CrossRef]

2005 (1)

A. Rohrbach, "Stiffness of optical traps: Quantitative agreement between experiment and electromagnetic theory," Phys. Rev. Lett. 95, 168,102 (2005).
[CrossRef]

2004 (3)

K. Neuman and S. Block, "Optical Trapping," Rev. Sci. Instrum. 75, 2787-2809 (2004).
[CrossRef]

D. L. J. Vossen, A. van der Horst, M. Dogterom, and A. van Blaaderen, "Optical tweezers and confocal microscopy for simultaneous three-dimensional manipulation and imaging in concentrated colloidal dispersions," Rev. Sci. Instrum. 75, 2960-2970 (2004).
[CrossRef]

W. R. Schief, R. H. Clark, A. H. Crevenna, and J. Howard, "Inhibition of kinesin motility by ADP and phosphate supports a hand-over-hand mechanism," Proc. Natl. Acad. Sci. U. S. A. 101, 1183-1188 (2004).
[CrossRef] [PubMed]

2003 (3)

C. Graf, D. L. J. Vossen, A. Imhof, and A. van Blaaderen, "A general method to coat colloidal particles with silica," Langmuir 19, 6693-6700 (2003).
[CrossRef]

D. G. Grier, "A revolution in optical manipulation," Nature 424, 810-816 (2003).
[CrossRef] [PubMed]

C. Bustamante, Z. Bryant, and S. B. Smith, "Ten years of tension: single-molecule DNA mechanics," Nature 421, 423-427 (2003).
[CrossRef] [PubMed]

2001 (2)

K. P. Velikov and A. van Blaaderen, "Synthesis and characterization of monodisperse core-shell colloidal spheres of zinc sulfide and silica," Langmuir 17, 4779-4786 (2001).
[CrossRef]

A. R. Clapp and R. B. Dickinson, "Direct measurement of static and dynamic forces between a colloidal particle and a flat surface using a single-beam gradient optical trap and evanescent wave light scattering," Langmuir 17, 2182-2191 (2001).
[CrossRef]

1999 (1)

A. D. Mehta, M. Rief, J. A. Spudich, D. A. Smith, and R. M. Simmons, "Single-molecule biomechanics with optical methods," Science 283, 1689-1695 (1999).
[CrossRef] [PubMed]

1998 (1)

G. V. Shivashankar, G. Stolovitzky, and A. Libchaber, "Backscattering from a tethered bead as a probe of DNA flexibility," Appl. Phys. Lett. 73, 291-293 (1998).
[CrossRef]

1997 (3)

A. Ashkin, "Optical trapping and manipulation of neutral particles using lasers," Proc. Natl. Acad. Sci. U. S. A. 94, 4853-4860 (1997).
[CrossRef] [PubMed]

D. G. Grier, "Optical tweezers in colloid and interface science," Curr. Opin. Colloid Interface Sci. 2, 264-270 (1997).
[CrossRef]

M. D. Wang, H. Yin, R. Landick, J. Gelles, and S. M. Block, "Stretching DNA with optical tweezers," Biophys. J. 72, 1335-1346 (1997).
[CrossRef] [PubMed]

1996 (1)

S. B. Smith, Y. J. Cui, and C. Bustamante, "Overstretching B-DNA: The elastic response of individual doublestranded and single-stranded DNA molecules," Science 271, 795-799 (1996).
[CrossRef] [PubMed]

1994 (2)

K. Svoboda and S. M. Block, "Biological Applications of Optical Forces," Annu. Rev. Biophys. Biomol. Struct. 23, 247-285 (1994).
[CrossRef] [PubMed]

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

1989 (1)

J. Howard, A. J. Hudspeth, and R. D. Vale, "Movement of Microtubules by Single Kinesin Molecules," Nature 342, 154-158 (1989).
[CrossRef] [PubMed]

1908 (1)

G. Mie, "Articles on the optical characteristics of turbid tubes, especially colloidal metal solutions," Ann. Phys. 25, 377-445 (1908).
[CrossRef]

Ashkin, A.

A. Ashkin, "Optical trapping and manipulation of neutral particles using lasers," Proc. Natl. Acad. Sci. U. S. A. 94, 4853-4860 (1997).
[CrossRef] [PubMed]

Beattie, K. L.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Bechinger, C.

C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, and C. Bechinger, "Direct measurement of critical Casimir forces," Nature 451, 172-175 (2008).
[CrossRef] [PubMed]

Block, S.

K. Neuman and S. Block, "Optical Trapping," Rev. Sci. Instrum. 75, 2787-2809 (2004).
[CrossRef]

Block, S. M.

M. D. Wang, H. Yin, R. Landick, J. Gelles, and S. M. Block, "Stretching DNA with optical tweezers," Biophys. J. 72, 1335-1346 (1997).
[CrossRef] [PubMed]

K. Svoboda and S. M. Block, "Biological Applications of Optical Forces," Annu. Rev. Biophys. Biomol. Struct. 23, 247-285 (1994).
[CrossRef] [PubMed]

Bormuth, V.

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

V. Bormuth, J. Howard, and E. Schaffer, "LED illumination for video-enhanced DIC imaging of single microtubules," J. Microsc. 226, 1-5 (2007).
[CrossRef] [PubMed]

Branczyk, A.M.

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
[CrossRef]

Bryant, Z.

C. Bustamante, Z. Bryant, and S. B. Smith, "Ten years of tension: single-molecule DNA mechanics," Nature 421, 423-427 (2003).
[CrossRef] [PubMed]

Burke, B. E.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Bustamante, C.

C. Bustamante, Z. Bryant, and S. B. Smith, "Ten years of tension: single-molecule DNA mechanics," Nature 421, 423-427 (2003).
[CrossRef] [PubMed]

S. B. Smith, Y. J. Cui, and C. Bustamante, "Overstretching B-DNA: The elastic response of individual doublestranded and single-stranded DNA molecules," Science 271, 795-799 (1996).
[CrossRef] [PubMed]

Clapp, A. R.

A. R. Clapp and R. B. Dickinson, "Direct measurement of static and dynamic forces between a colloidal particle and a flat surface using a single-beam gradient optical trap and evanescent wave light scattering," Langmuir 17, 2182-2191 (2001).
[CrossRef]

Clark, R. H.

W. R. Schief, R. H. Clark, A. H. Crevenna, and J. Howard, "Inhibition of kinesin motility by ADP and phosphate supports a hand-over-hand mechanism," Proc. Natl. Acad. Sci. U. S. A. 101, 1183-1188 (2004).
[CrossRef] [PubMed]

Crevenna, A. H.

W. R. Schief, R. H. Clark, A. H. Crevenna, and J. Howard, "Inhibition of kinesin motility by ADP and phosphate supports a hand-over-hand mechanism," Proc. Natl. Acad. Sci. U. S. A. 101, 1183-1188 (2004).
[CrossRef] [PubMed]

Cui, Y. J.

S. B. Smith, Y. J. Cui, and C. Bustamante, "Overstretching B-DNA: The elastic response of individual doublestranded and single-stranded DNA molecules," Science 271, 795-799 (1996).
[CrossRef] [PubMed]

Dekker, C.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Dekker, N. H.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Dickinson, R. B.

A. R. Clapp and R. B. Dickinson, "Direct measurement of static and dynamic forces between a colloidal particle and a flat surface using a single-beam gradient optical trap and evanescent wave light scattering," Langmuir 17, 2182-2191 (2001).
[CrossRef]

Dietrich, S.

C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, and C. Bechinger, "Direct measurement of critical Casimir forces," Nature 451, 172-175 (2008).
[CrossRef] [PubMed]

Diez, S.

C. Leduc, F. Ruhnow, J. Howard, and S. Diez, "Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors," Proc. Natl. Acad. Sci. U. S. A. 104, 10847-10852 (2007).
[CrossRef] [PubMed]

Dogterom, M.

D. L. J. Vossen, A. van der Horst, M. Dogterom, and A. van Blaaderen, "Optical tweezers and confocal microscopy for simultaneous three-dimensional manipulation and imaging in concentrated colloidal dispersions," Rev. Sci. Instrum. 75, 2960-2970 (2004).
[CrossRef]

Eggers, M. D.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Ehrlich, D. J.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Fowler, R.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Gambassi, A.

C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, and C. Bechinger, "Direct measurement of critical Casimir forces," Nature 451, 172-175 (2008).
[CrossRef] [PubMed]

Gelles, J.

M. D. Wang, H. Yin, R. Landick, J. Gelles, and S. M. Block, "Stretching DNA with optical tweezers," Biophys. J. 72, 1335-1346 (1997).
[CrossRef] [PubMed]

Graf, C.

C. Graf, D. L. J. Vossen, A. Imhof, and A. van Blaaderen, "A general method to coat colloidal particles with silica," Langmuir 19, 6693-6700 (2003).
[CrossRef]

Grier, D. G.

D. G. Grier, "A revolution in optical manipulation," Nature 424, 810-816 (2003).
[CrossRef] [PubMed]

D. G. Grier, "Optical tweezers in colloid and interface science," Curr. Opin. Colloid Interface Sci. 2, 264-270 (1997).
[CrossRef]

Heckenberg, N. R.

Y. Hu, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Antireflection coating for improved optical trapping," J. Appl. Phys. 103, 093119 (2008).
[CrossRef]

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
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G. Knoner, S. Parkin, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Measurement of the index of refraction of single microparticles," Phys. Rev. Lett. 97, 157402 (2006).
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C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, and C. Bechinger, "Direct measurement of critical Casimir forces," Nature 451, 172-175 (2008).
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C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, and C. Bechinger, "Direct measurement of critical Casimir forces," Nature 451, 172-175 (2008).
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Hogan, M. E.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
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J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
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Howard, J.

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

E. Schaffer, S. F. Nørrelykke, and J. Howard, "Surface forces and drag coefficients of microspheres near a plane surface measured with optical tweezers," Langmuir 23, 3654-3665 (2007).
[CrossRef] [PubMed]

C. Leduc, F. Ruhnow, J. Howard, and S. Diez, "Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors," Proc. Natl. Acad. Sci. U. S. A. 104, 10847-10852 (2007).
[CrossRef] [PubMed]

V. Bormuth, J. Howard, and E. Schaffer, "LED illumination for video-enhanced DIC imaging of single microtubules," J. Microsc. 226, 1-5 (2007).
[CrossRef] [PubMed]

W. R. Schief, R. H. Clark, A. H. Crevenna, and J. Howard, "Inhibition of kinesin motility by ADP and phosphate supports a hand-over-hand mechanism," Proc. Natl. Acad. Sci. U. S. A. 101, 1183-1188 (2004).
[CrossRef] [PubMed]

J. Howard, A. J. Hudspeth, and R. D. Vale, "Movement of Microtubules by Single Kinesin Molecules," Nature 342, 154-158 (1989).
[CrossRef] [PubMed]

Hu, Y.

Y. Hu, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Antireflection coating for improved optical trapping," J. Appl. Phys. 103, 093119 (2008).
[CrossRef]

Hudspeth, A. J.

J. Howard, A. J. Hudspeth, and R. D. Vale, "Movement of Microtubules by Single Kinesin Molecules," Nature 342, 154-158 (1989).
[CrossRef] [PubMed]

Imhof, A.

C. Graf, D. L. J. Vossen, A. Imhof, and A. van Blaaderen, "A general method to coat colloidal particles with silica," Langmuir 19, 6693-6700 (2003).
[CrossRef]

Jannasch, A.

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

Katz, C.

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

Keyser, U. F.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Knoner, G.

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
[CrossRef]

G. Knoner, S. Parkin, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Measurement of the index of refraction of single microparticles," Phys. Rev. Lett. 97, 157402 (2006).
[CrossRef] [PubMed]

Koeleman, B. N.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Kosicki, B. B.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Krapf, D.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Lamture, J. B.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

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M. D. Wang, H. Yin, R. Landick, J. Gelles, and S. M. Block, "Stretching DNA with optical tweezers," Biophys. J. 72, 1335-1346 (1997).
[CrossRef] [PubMed]

Leduc, C.

C. Leduc, F. Ruhnow, J. Howard, and S. Diez, "Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors," Proc. Natl. Acad. Sci. U. S. A. 104, 10847-10852 (2007).
[CrossRef] [PubMed]

Lemay, S. G.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Libchaber, A.

G. V. Shivashankar, G. Stolovitzky, and A. Libchaber, "Backscattering from a tethered bead as a probe of DNA flexibility," Appl. Phys. Lett. 73, 291-293 (1998).
[CrossRef]

Loke, V. L. Y.

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
[CrossRef]

Mazolli, A.

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli, and P. A. M. Neto, "Characterization of objective transmittance for optical tweezers," Appl. Opt. 45, 4263-4269 (2006).
[CrossRef] [PubMed]

Mehta, A. D.

A. D. Mehta, M. Rief, J. A. Spudich, D. A. Smith, and R. M. Simmons, "Single-molecule biomechanics with optical methods," Science 283, 1689-1695 (1999).
[CrossRef] [PubMed]

Mesquita, O. N.

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli, and P. A. M. Neto, "Characterization of objective transmittance for optical tweezers," Appl. Opt. 45, 4263-4269 (2006).
[CrossRef] [PubMed]

Mie, G.

G. Mie, "Articles on the optical characteristics of turbid tubes, especially colloidal metal solutions," Ann. Phys. 25, 377-445 (1908).
[CrossRef]

Neto, P. A. M.

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli, and P. A. M. Neto, "Characterization of objective transmittance for optical tweezers," Appl. Opt. 45, 4263-4269 (2006).
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Neuman, K.

K. Neuman and S. Block, "Optical Trapping," Rev. Sci. Instrum. 75, 2787-2809 (2004).
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Nieminen, T. A.

Y. Hu, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Antireflection coating for improved optical trapping," J. Appl. Phys. 103, 093119 (2008).
[CrossRef]

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
[CrossRef]

G. Knoner, S. Parkin, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Measurement of the index of refraction of single microparticles," Phys. Rev. Lett. 97, 157402 (2006).
[CrossRef] [PubMed]

Noom, M. C.

M. C. Noom, B. van den Broek, J. van Mameren, and G. J. L. Wuite, "Visualizing single DNA-bound proteins using DNA as a scanning probe," Nat. Method 4, 1031-1036 (2007).
[CrossRef]

Nørrelykke, S. F.

E. Schaffer, S. F. Nørrelykke, and J. Howard, "Surface forces and drag coefficients of microspheres near a plane surface measured with optical tweezers," Langmuir 23, 3654-3665 (2007).
[CrossRef] [PubMed]

Nussenzveig, H. M.

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

Oddershede, L. B.

Parkin, S.

G. Knoner, S. Parkin, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Measurement of the index of refraction of single microparticles," Phys. Rev. Lett. 97, 157402 (2006).
[CrossRef] [PubMed]

Reich, R. K.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Reihani, S. N. S.

Rief, M.

A. D. Mehta, M. Rief, J. A. Spudich, D. A. Smith, and R. M. Simmons, "Single-molecule biomechanics with optical methods," Science 283, 1689-1695 (1999).
[CrossRef] [PubMed]

Rocha, M. S.

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli, and P. A. M. Neto, "Characterization of objective transmittance for optical tweezers," Appl. Opt. 45, 4263-4269 (2006).
[CrossRef] [PubMed]

Rohrbach, A.

A. Rohrbach, "Stiffness of optical traps: Quantitative agreement between experiment and electromagnetic theory," Phys. Rev. Lett. 95, 168,102 (2005).
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Rubinsztein-Dunlop, H.

Y. Hu, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Antireflection coating for improved optical trapping," J. Appl. Phys. 103, 093119 (2008).
[CrossRef]

G. Knoner, S. Parkin, T. A. Nieminen, N. R. Heckenberg, and H. Rubinsztein-Dunlop, "Measurement of the index of refraction of single microparticles," Phys. Rev. Lett. 97, 157402 (2006).
[CrossRef] [PubMed]

Ruhnow, F.

C. Leduc, F. Ruhnow, J. Howard, and S. Diez, "Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors," Proc. Natl. Acad. Sci. U. S. A. 104, 10847-10852 (2007).
[CrossRef] [PubMed]

Schaffer, E.

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

E. Schaffer, S. F. Nørrelykke, and J. Howard, "Surface forces and drag coefficients of microspheres near a plane surface measured with optical tweezers," Langmuir 23, 3654-3665 (2007).
[CrossRef] [PubMed]

V. Bormuth, J. Howard, and E. Schaffer, "LED illumination for video-enhanced DIC imaging of single microtubules," J. Microsc. 226, 1-5 (2007).
[CrossRef] [PubMed]

Schief, W. R.

W. R. Schief, R. H. Clark, A. H. Crevenna, and J. Howard, "Inhibition of kinesin motility by ADP and phosphate supports a hand-over-hand mechanism," Proc. Natl. Acad. Sci. U. S. A. 101, 1183-1188 (2004).
[CrossRef] [PubMed]

Shivashankar, G. V.

G. V. Shivashankar, G. Stolovitzky, and A. Libchaber, "Backscattering from a tethered bead as a probe of DNA flexibility," Appl. Phys. Lett. 73, 291-293 (1998).
[CrossRef]

Simmons, R. M.

A. D. Mehta, M. Rief, J. A. Spudich, D. A. Smith, and R. M. Simmons, "Single-molecule biomechanics with optical methods," Science 283, 1689-1695 (1999).
[CrossRef] [PubMed]

Smeets, R. M. M.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

Smith, D. A.

A. D. Mehta, M. Rief, J. A. Spudich, D. A. Smith, and R. M. Simmons, "Single-molecule biomechanics with optical methods," Science 283, 1689-1695 (1999).
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C. Bustamante, Z. Bryant, and S. B. Smith, "Ten years of tension: single-molecule DNA mechanics," Nature 421, 423-427 (2003).
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S. B. Smith, Y. J. Cui, and C. Bustamante, "Overstretching B-DNA: The elastic response of individual doublestranded and single-stranded DNA molecules," Science 271, 795-799 (1996).
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Smith, S. R.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Spudich, J. A.

A. D. Mehta, M. Rief, J. A. Spudich, D. A. Smith, and R. M. Simmons, "Single-molecule biomechanics with optical methods," Science 283, 1689-1695 (1999).
[CrossRef] [PubMed]

Stilgoe, A. B.

T. A. Nieminen, V. L. Y. Loke, A. B. Stilgoe, G. Knoner, A.M. Branczyk, N. R. Heckenberg, and H. Rubinsztein- Dunlop, "Optical tweezers computational toolbox," J. Optic. Pure. Appl. Optic. 9, S196-S203 (2007).
[CrossRef]

Stolovitzky, G.

G. V. Shivashankar, G. Stolovitzky, and A. Libchaber, "Backscattering from a tethered bead as a probe of DNA flexibility," Appl. Phys. Lett. 73, 291-293 (1998).
[CrossRef]

Svoboda, K.

K. Svoboda and S. M. Block, "Biological Applications of Optical Forces," Annu. Rev. Biophys. Biomol. Struct. 23, 247-285 (1994).
[CrossRef] [PubMed]

Vale, R. D.

J. Howard, A. J. Hudspeth, and R. D. Vale, "Movement of Microtubules by Single Kinesin Molecules," Nature 342, 154-158 (1989).
[CrossRef] [PubMed]

van Blaaderen, A.

A. Jannasch, V. Bormuth, C. Katz, A. van Blaaderen, J. Howard, and E. Schaffer, "Coated microspheres as enhanced probes for optical trapping," Proc. SPIE, submitted (2008).

D. L. J. Vossen, A. van der Horst, M. Dogterom, and A. van Blaaderen, "Optical tweezers and confocal microscopy for simultaneous three-dimensional manipulation and imaging in concentrated colloidal dispersions," Rev. Sci. Instrum. 75, 2960-2970 (2004).
[CrossRef]

C. Graf, D. L. J. Vossen, A. Imhof, and A. van Blaaderen, "A general method to coat colloidal particles with silica," Langmuir 19, 6693-6700 (2003).
[CrossRef]

K. P. Velikov and A. van Blaaderen, "Synthesis and characterization of monodisperse core-shell colloidal spheres of zinc sulfide and silica," Langmuir 17, 4779-4786 (2001).
[CrossRef]

van den Broek, B.

M. C. Noom, B. van den Broek, J. van Mameren, and G. J. L. Wuite, "Visualizing single DNA-bound proteins using DNA as a scanning probe," Nat. Method 4, 1031-1036 (2007).
[CrossRef]

van der Horst, A.

D. L. J. Vossen, A. van der Horst, M. Dogterom, and A. van Blaaderen, "Optical tweezers and confocal microscopy for simultaneous three-dimensional manipulation and imaging in concentrated colloidal dispersions," Rev. Sci. Instrum. 75, 2960-2970 (2004).
[CrossRef]

Van Dorp, S.

U. F. Keyser, B. N. Koeleman, S. Van Dorp, D. Krapf, R. M. M. Smeets, S. G. Lemay, N. H. Dekker, and C. Dekker, "Direct force measurements on DNA in a solid-state nanopore," Nature Phys. 2, 473-477 (2006).
[CrossRef]

van Mameren, J.

M. C. Noom, B. van den Broek, J. van Mameren, and G. J. L. Wuite, "Visualizing single DNA-bound proteins using DNA as a scanning probe," Nat. Method 4, 1031-1036 (2007).
[CrossRef]

Varma, R. S.

J. B. Lamture, K. L. Beattie, B. E. Burke, M. D. Eggers, D. J. Ehrlich, R. Fowler, M. A. Hollis, B. B. Kosicki, R. K. Reich, S. R. Smith, R. S. Varma, and M. E. Hogan, "Direct-Detection of Nucleic-Acid Hybridization on the Surface of a Charge-Coupled-Device," Nucleic Acids Res. 22, 2121-2125 (1994).
[CrossRef] [PubMed]

Velikov, K. P.

K. P. Velikov and A. van Blaaderen, "Synthesis and characterization of monodisperse core-shell colloidal spheres of zinc sulfide and silica," Langmuir 17, 4779-4786 (2001).
[CrossRef]

Viana, N. B.

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
[CrossRef]

N. B. Viana, M. S. Rocha, O. N. Mesquita, A. Mazolli, and P. A. M. Neto, "Characterization of objective transmittance for optical tweezers," Appl. Opt. 45, 4263-4269 (2006).
[CrossRef] [PubMed]

Vossen, D. L. J.

D. L. J. Vossen, A. van der Horst, M. Dogterom, and A. van Blaaderen, "Optical tweezers and confocal microscopy for simultaneous three-dimensional manipulation and imaging in concentrated colloidal dispersions," Rev. Sci. Instrum. 75, 2960-2970 (2004).
[CrossRef]

C. Graf, D. L. J. Vossen, A. Imhof, and A. van Blaaderen, "A general method to coat colloidal particles with silica," Langmuir 19, 6693-6700 (2003).
[CrossRef]

Wang, M. D.

M. D. Wang, H. Yin, R. Landick, J. Gelles, and S. M. Block, "Stretching DNA with optical tweezers," Biophys. J. 72, 1335-1346 (1997).
[CrossRef] [PubMed]

Wuite, G. J. L.

M. C. Noom, B. van den Broek, J. van Mameren, and G. J. L. Wuite, "Visualizing single DNA-bound proteins using DNA as a scanning probe," Nat. Method 4, 1031-1036 (2007).
[CrossRef]

Yin, H.

M. D. Wang, H. Yin, R. Landick, J. Gelles, and S. M. Block, "Stretching DNA with optical tweezers," Biophys. J. 72, 1335-1346 (1997).
[CrossRef] [PubMed]

Ann. Phys. (1)

G. Mie, "Articles on the optical characteristics of turbid tubes, especially colloidal metal solutions," Ann. Phys. 25, 377-445 (1908).
[CrossRef]

Annu. Rev. Biophys. Biomol. Struct. (1)

K. Svoboda and S. M. Block, "Biological Applications of Optical Forces," Annu. Rev. Biophys. Biomol. Struct. 23, 247-285 (1994).
[CrossRef] [PubMed]

Appl. Opt. (1)

Appl. Phys. Lett. (2)

N. B. Viana, A. Mazolli, P. A. M. Neto, H. M. Nussenzveig, M. S. Rocha, and O. N. Mesquita, "Absolute calibration of optical tweezers," Appl. Phys. Lett. 88, 131110 (2006).
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Figures (6)

Fig. 1.
Fig. 1.

(a) Setup geometry: A coated microsphere (bead) with diameter D is trapped in a tightly focussed, linearly polarized laser beam near a surface in an aqueous medium. The axial direction (propagation direction of the laser) is referred to as z. The laser is polarized in the y-direction. Light reflected back from the individual bead interfaces interferes and forms a standing light wave between the surface and the bead. (b) Schematic drawing of the silica (SiOx, top), silica-coated polystyrene (PS+SiOx, middle), and polystyrene (PS, bottom) microspheres. Refractive indices n are for a wavelength of 1064 nm. (c) Bright field and (d) differential interference contrast microscopy images of the respective microspheres in (b). (e) Transmission electron microscopy images of the coated microspheres. (c–e) Scale: All microspheres have an outer diameter of ≈1.5 µm.

Fig. 2.
Fig. 2.

(a) Lateral y, (b) axial z trap stiffness, and (c) lateral y escape force as a function of bead diameter for SiOx (○), PS (•) and SiOx-coated PS (⊙,⊙). The coated beads had two different cores: for D≤1.5 µm the core diameter was 913 nm (⊙) and for D>1.5 µm the core size was 960 nm (⊙). The data points marked with ∞ were measured in a glycerol solution that index-matched the shell (see text). The symbols are averages (N≿6) for each bead type. Errors are standard deviations and plotted if they were larger than the symbol size. Rayleigh (…, trap stiffness κD 3) and geometric optics (- - -, κD -1) limits for PS. The other lines are Mie theory calculations. The laser power in (c) was 3× lower than in (a,b).

Fig. 3.
Fig. 3.

Polarization dependence of the lateral trap stiffness as a function of bead diameter for SiOx (○), PS (…) and SiOx-coated PS (⊙,⊙). The plot shows the relative difference between the lateral trap stiffnesses 2(κy -κx )/(κx +κy ). The laser was linearly polarized in the y-direction. The lines are the Mie theory results.

Fig. 4.
Fig. 4.

(a) Lateral detector signal measured as a function of lateral stage position for surface-immobilized beads. (b) Axial displacement sensitivity as a function of stage height for the three different bead types using the same laser intensity. At stage height zero, microspheres touch the surface. The displacement sensitivity increases linearly with distance to the surface due to spherical aberrations [10]. Oscillations are due to a standing light wave between the surface and the bead. (a,b) 1.5 µm-diameter bead: ---- PS+SiOx,—SiOx, --PS; 0.9µm-diameter bead: - - - PS.

Fig. 5.
Fig. 5.

(a) High-force kinesin-1 motor protein assay. A NeutrAvidin modified coated microsphere was attached to a biotinylated microtubule transported by multiple motors that are attached to the coverslip surface (10 µM ATP, see Methods). The magenta rectangle indicates the region that is displayed in (b) with a higher magnification. (b) Close-up view of the region marked in (a). No steps are discernable. (c) DNA force-extension curve. A 1 µm-long DNA (----) was pulled laterally (see Methods and [18]). An extensible wormlike chain model (----) describes the data well. (a–c) We used 1.5 µm-diameter coated beads (PS+SiOx).

Fig. 6.
Fig. 6.

Axial equilibrium position (----PS+SiOx, —SiOx, --PS; left-hand scale) and normalized oscillation amplitude of laser intensity (○SiOx, …PS, ⊙SiOx+PS; right-hand scale) as a function of bead diameter D. The inset shows the equilibrium position with a rescaled abscissa: the diameter in units of the laser wavelength inside the bead.

Tables (1)

Tables Icon

Table 1. Specifications for the coated microspheres: mean±standard deviation in µm (poly-dispersity a in %, number of measurements N if known). The total diameter D was measured with transmission electron microscopy (TEM) and our optical tweezers calibration method.

Equations (10)

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F scat = n medium S σ c
σ = 2 3 π 5 ( n medium λ ) 4 D 6 ( m 2 1 m 2 + 2 ) 2
m 2 1 m 2 + 2 = n bead 2 n medium 2 n bead 2 + 2 n medium 2 = ( n bead n medium ) ( n bead + n medium ) n bead 2 + 2 n medium 2 Δ n
F scat Δ n 2 .
F grad = α 2 E 2
α = 1 8 n medium D 3 ( m 2 1 m 2 + 2 ) .
F grad Δ n .
F scat ( n bead n medium n bead + n medium ) 2 Δ n 2 .
θ 1 n medium = θ 2 n bead .
F grad 2 sin ( θ 1 θ 2 ) 2 ( θ 1 θ 2 ) = 2 θ 1 n bread ( n bead n medium ) Δ n .

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