Abstract

We describe the application of infrared optical tweezers to the in situ microparticle analysis of marine phytoplankton cells. A Nd:YAG laser (λ = 1064 nm) trap is used to confine and manipulate single Nannochloris and Synechococcus cells in an enriched seawater medium while spectral fluorescence and Lorenz–Mie backscatter signals are simultaneously acquired under a variety of excitation and trapping conditions. Variations in the measured fluorescence intensities of chlorophyll a (Chl a) and phycoerythrin pigments in phytoplankton cells are observed. These variations are related, in part, to basic intrasample variability, but they also indicate that increasing ultraviolet-exposure time and infrared trapping power may have short-term effects on cellular physiology that are related to Chl a photobleaching and laser-induced heating, respectively. The use of optical tweezers to study the factors that affect marine cell physiology and the processes of absorption, scattering, and attenuation by individual cells, organisms, and particulate matter that contribute to optical closure on a microscopic scale are also described.

© 1995 Optical Society of America

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  5. J. B. Soohoo, D. A. Kiefer, D. J. Collins, I. S. McDermid, “In vivo fluorescence excitation and absorption spectra of marine phytoplankton: I. Taxonomic characteristics and responses to photoadaptation,” J. Plankton Res. 8, 197–214 (1986).
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    [CrossRef] [PubMed]
  8. S. G. Ackleson, R. W. Spinrad, “Size and refractive index of individual marine particulates: a flow cytometric approach,” Appl. Opt. 27, 1270–1277 (1988).
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  9. R. Iturriaga, B. G. Mitchell, D. A. Kiefer, “Microphotometric analysis of individual particle absorption spectra,” Limnol. Oceanogr. 33, 128–135 (1988).
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  11. S. L. Bower, R. Iturriaga, “Preparation of natural phytoplankton communities to preserve spectral fluorescence properties,” in Ocean Optics XI, G. D. Gilbert, ed., Proc. Soc. Photo-Opt. Instrum. Eng.1750, 224–232 (1992).
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    [CrossRef] [PubMed]
  30. Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).
  31. H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
    [CrossRef] [PubMed]
  32. I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
    [CrossRef] [PubMed]
  33. W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).
  34. S. Sato, M. Ohyumi, H. Shibata, H. Inaba, “Optical trapping of small particles using a 1.3-μm compact InGaAsP diode laser,” Opt. Lett. 16, 282–284 (1991).
    [CrossRef] [PubMed]
  35. G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
    [CrossRef]
  36. A. Constable, J. Kim, J. Mervis, F. Zarinetchi, M. Prentiss, “Demonstration of a fiber-optical light-force trap,” Opt. Lett. 18, 1867–1869 (1993).
    [CrossRef] [PubMed]
  37. E. R. Lyons, G. J. Sonek, “Confinement and bistability in a tapered hemispherically lensed optical fiber trap,” Appl. Phys. Lett. 66, 1584–1586 (1995).
    [CrossRef]
  38. A. Bricaud, A. Morel, “Light attenuation and scattering by phytoplanktonic cells: a theoretical modeling,” Appl. Opt. 25, 571–580 (1986).
    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]

1995

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

E. R. Lyons, G. J. Sonek, “Confinement and bistability in a tapered hemispherically lensed optical fiber trap,” Appl. Phys. Lett. 66, 1584–1586 (1995).
[CrossRef]

1994

G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
[CrossRef]

W. H. Wright, G. J. Sonek, M. W. Berns, “Parametric study of the forces on microspheres held by optical tweezers,” Appl. Opt. 33, 1735–1748 (1994).
[CrossRef] [PubMed]

K. Svoboda, S. M. Block, “Biological applications of optical forces,” Ann. Rev. Biophys. Biomol. Struct. 23, 247–285 (1994).
[CrossRef]

1993

I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
[CrossRef] [PubMed]

T. J. Cowles, R. A. Desiderio, S. Neuer, “In situ characterization of phytoplankton from vertical profiles of fluorescence emission spectra,” Mar. Biol. 115, 217–222 (1993).
[CrossRef]

T. J. Cowles, R. A. Desiderio, “Resolution of biological microstructure through in situ fluorescence emission spectra,” Oceanogr. 6, 105–111 (1993).

R. A. Desiderio, T. J. Cowles, J. N. Moum, M. Myrick, “Microstructure profiles of laser-induced chlorophyll fluorescence spectra: evaluation of backscatter and forward-scatter fiber-optic sensors,” J. Atmos. Oceanic Technol. 10, 209–224 (1993).
[CrossRef]

A. Constable, J. Kim, J. Mervis, F. Zarinetchi, M. Prentiss, “Demonstration of a fiber-optical light-force trap,” Opt. Lett. 18, 1867–1869 (1993).
[CrossRef] [PubMed]

1991

S. Sato, M. Ohyumi, H. Shibata, H. Inaba, “Optical trapping of small particles using a 1.3-μm compact InGaAsP diode laser,” Opt. Lett. 16, 282–284 (1991).
[CrossRef] [PubMed]

H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
[CrossRef] [PubMed]

1990

D. Stramski, A. Morel, “Optical properties of photosynthetic picoplankton in different physiological states as affected by growth irradiance,” Deep Sea Res. 37, 245–266 (1990).
[CrossRef]

M. L. Myrick, S. M. Angel, R. Desiderio, “Comparison of some fiber optic configurations for measurement of luminescence and Raman scattering,” Appl. Opt. 29, 1333–1344 (1990).
[CrossRef] [PubMed]

1989

T. J. Cowles, J. N. Moum, R. A. Desiderio, S. M. Angel, “In situ monitoring of ocean chorophyll via laser-induced fluorescence backscattering through an optical fiber,” Appl. Opt. 28, 595–600 (1989).
[CrossRef] [PubMed]

J. R. V. Zaneveld, “An asymptotic closure theory for irradiance in the sea and its inversion to obtain the inherent optical properties,” Limnol. Oceanogr. 34, 1442–1452 (1989).
[CrossRef]

R. Iturriaga, D. A. Siegel, “Microphotometric characterization of phytoplankton and detrital absorption properties in the Sargasso Sea,” Limnol. Oceanogr. 34, 1706–1726 (1989).
[CrossRef]

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

1988

L. Campbell, R. H. Iturriaga, “Identification of Synechococcus spp. in the Sargasso Sea by immunofluorescence and fluorescence excitation spectroscopy performed on individual cells,” Limnol. Oceanogr. 35, 1196–1201 (1988).
[CrossRef]

R. Iturriaga, B. G. Mitchell, D. A. Kiefer, “Microphotometric analysis of individual particle absorption spectra,” Limnol. Oceanogr. 33, 128–135 (1988).
[CrossRef]

S. G. Ackleson, R. W. Spinrad, C. M. Yentsch, J. Brown, W. Korjeff-Bellows, “Phytoplankton optical properties: flow cytometric examinations of dilution-induced effects,” Appl. Opt. 27, 1262–1269 (1988).
[CrossRef] [PubMed]

S. G. Ackleson, R. W. Spinrad, “Size and refractive index of individual marine particulates: a flow cytometric approach,” Appl. Opt. 27, 1270–1277 (1988).
[CrossRef] [PubMed]

1987

T. N. Buican, M. J. Smith, H. A. Crissman, G. C. Salzman, C. C. Stewart, J. C. Martin, “Automated single-cell manipulation and sorting by light trapping,” Appl. Opt. 26, 5311–5316 (1987).
[CrossRef] [PubMed]

A. Ashkin, J. M. Dziedzic, T. M. Yamane, “Optical trapping and manipulation of single cells using infrared laser beams,” Nature 330, 769–771 (1987).
[CrossRef] [PubMed]

1986

1985

C. S. Yentsch, D. A. Phinney, “Spectral fluorescence: an ataxonomic tool for studying the structure of phytoplankton populations,” J. Plankton Res. 7, 617–632 (1985).
[CrossRef]

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

1963

C. S. Yentsch, D. W. Menzel, “A method for the determination of phytoplankton chlorophyll and phaeophytin by fluorescence,” Deep Sea Res. 10, 221–231 (1963).

Ackleson, S. G.

Angel, S. M.

Asch, R. H.

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

Ashkin, A.

A. Ashkin, J. M. Dziedzic, T. M. Yamane, “Optical trapping and manipulation of single cells using infrared laser beams,” Nature 330, 769–771 (1987).
[CrossRef] [PubMed]

A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, S. Chu, “Observation of a single-beam gradient force optical trap for dielectric particles,” Opt. Lett. 11, 288–290 (1986).
[CrossRef] [PubMed]

Berns, M. W.

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
[CrossRef]

W. H. Wright, G. J. Sonek, M. W. Berns, “Parametric study of the forces on microspheres held by optical tweezers,” Appl. Opt. 33, 1735–1748 (1994).
[CrossRef] [PubMed]

I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
[CrossRef] [PubMed]

H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
[CrossRef] [PubMed]

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).

Bjorkholm, J. E.

Block, S. M.

K. Svoboda, S. M. Block, “Biological applications of optical forces,” Ann. Rev. Biophys. Biomol. Struct. 23, 247–285 (1994).
[CrossRef]

Bohren, C. F.

C. F. Bohren, D. R. Huffman, Absorption and Scattering of Light by Small Particles (Wiley, New York, 1983).

Born, M.

M. Born, E. Wolf, Principles of Optics (Pergamon, Oxford, 1987), Sec. 13.5.1.

Bower, S. L.

S. L. Bower, R. Iturriaga, “Preparation of natural phytoplankton communities to preserve spectral fluorescence properties,” in Ocean Optics XI, G. D. Gilbert, ed., Proc. Soc. Photo-Opt. Instrum. Eng.1750, 224–232 (1992).

Bricaud, A.

Brown, J.

Brown, J. F.

Buican, T. N.

Campbell, L.

L. Campbell, R. H. Iturriaga, “Identification of Synechococcus spp. in the Sargasso Sea by immunofluorescence and fluorescence excitation spectroscopy performed on individual cells,” Limnol. Oceanogr. 35, 1196–1201 (1988).
[CrossRef]

Chapman, C. F.

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

Cheng, D. K.

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

Chu, S.

Collins, D. J.

J. B. Soohoo, D. A. Kiefer, D. J. Collins, I. S. McDermid, “In vivo fluorescence excitation and absorption spectra of marine phytoplankton: I. Taxonomic characteristics and responses to photoadaptation,” J. Plankton Res. 8, 197–214 (1986).
[CrossRef]

Constable, A.

Cowles, T. J.

R. A. Desiderio, T. J. Cowles, J. N. Moum, M. Myrick, “Microstructure profiles of laser-induced chlorophyll fluorescence spectra: evaluation of backscatter and forward-scatter fiber-optic sensors,” J. Atmos. Oceanic Technol. 10, 209–224 (1993).
[CrossRef]

T. J. Cowles, R. A. Desiderio, S. Neuer, “In situ characterization of phytoplankton from vertical profiles of fluorescence emission spectra,” Mar. Biol. 115, 217–222 (1993).
[CrossRef]

T. J. Cowles, R. A. Desiderio, “Resolution of biological microstructure through in situ fluorescence emission spectra,” Oceanogr. 6, 105–111 (1993).

T. J. Cowles, J. N. Moum, R. A. Desiderio, S. M. Angel, “In situ monitoring of ocean chorophyll via laser-induced fluorescence backscattering through an optical fiber,” Appl. Opt. 28, 595–600 (1989).
[CrossRef] [PubMed]

Crissman, H. A.

Desiderio, R.

Desiderio, R. A.

T. J. Cowles, R. A. Desiderio, “Resolution of biological microstructure through in situ fluorescence emission spectra,” Oceanogr. 6, 105–111 (1993).

R. A. Desiderio, T. J. Cowles, J. N. Moum, M. Myrick, “Microstructure profiles of laser-induced chlorophyll fluorescence spectra: evaluation of backscatter and forward-scatter fiber-optic sensors,” J. Atmos. Oceanic Technol. 10, 209–224 (1993).
[CrossRef]

T. J. Cowles, R. A. Desiderio, S. Neuer, “In situ characterization of phytoplankton from vertical profiles of fluorescence emission spectra,” Mar. Biol. 115, 217–222 (1993).
[CrossRef]

T. J. Cowles, J. N. Moum, R. A. Desiderio, S. M. Angel, “In situ monitoring of ocean chorophyll via laser-induced fluorescence backscattering through an optical fiber,” Appl. Opt. 28, 595–600 (1989).
[CrossRef] [PubMed]

Dziedzic, J. M.

A. Ashkin, J. M. Dziedzic, T. M. Yamane, “Optical trapping and manipulation of single cells using infrared laser beams,” Nature 330, 769–771 (1987).
[CrossRef] [PubMed]

A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, S. Chu, “Observation of a single-beam gradient force optical trap for dielectric particles,” Opt. Lett. 11, 288–290 (1986).
[CrossRef] [PubMed]

Escandon, G. J.

G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
[CrossRef]

Guillard, R. R. L.

R. R. L. Guillard, “Culture of phytoplankton for feeding marine invertebrates,” in Culture of Marine Invertebrate Animals, W. L. Smith, M. H. Chanley, eds. (Plenum, New York, 1975), pp. 29–60.
[CrossRef]

He, W.

H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
[CrossRef] [PubMed]

Horan, P. K.

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

Huffman, D. R.

C. F. Bohren, D. R. Huffman, Absorption and Scattering of Light by Small Particles (Wiley, New York, 1983).

Inaba, H.

Iturriaga, R.

R. Iturriaga, D. A. Siegel, “Microphotometric characterization of phytoplankton and detrital absorption properties in the Sargasso Sea,” Limnol. Oceanogr. 34, 1706–1726 (1989).
[CrossRef]

R. Iturriaga, B. G. Mitchell, D. A. Kiefer, “Microphotometric analysis of individual particle absorption spectra,” Limnol. Oceanogr. 33, 128–135 (1988).
[CrossRef]

S. L. Bower, R. Iturriaga, “Preparation of natural phytoplankton communities to preserve spectral fluorescence properties,” in Ocean Optics XI, G. D. Gilbert, ed., Proc. Soc. Photo-Opt. Instrum. Eng.1750, 224–232 (1992).

Iturriaga, R. H.

L. Campbell, R. H. Iturriaga, “Identification of Synechococcus spp. in the Sargasso Sea by immunofluorescence and fluorescence excitation spectroscopy performed on individual cells,” Limnol. Oceanogr. 35, 1196–1201 (1988).
[CrossRef]

Keller, R. A.

W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).

Kiefer, D. A.

R. Iturriaga, B. G. Mitchell, D. A. Kiefer, “Microphotometric analysis of individual particle absorption spectra,” Limnol. Oceanogr. 33, 128–135 (1988).
[CrossRef]

J. B. Soohoo, D. A. Kiefer, D. J. Collins, I. S. McDermid, “In vivo fluorescence excitation and absorption spectra of marine phytoplankton: I. Taxonomic characteristics and responses to photoadaptation,” J. Plankton Res. 8, 197–214 (1986).
[CrossRef]

Kim, J.

Korjeff-Bellows, W.

Liang, H.

I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
[CrossRef] [PubMed]

H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
[CrossRef] [PubMed]

Liu, Y.

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
[CrossRef]

W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).

Lyons, E. R.

E. R. Lyons, G. J. Sonek, “Confinement and bistability in a tapered hemispherically lensed optical fiber trap,” Appl. Phys. Lett. 66, 1584–1586 (1995).
[CrossRef]

Martin, J. C.

McDermid, I. S.

J. B. Soohoo, D. A. Kiefer, D. J. Collins, I. S. McDermid, “In vivo fluorescence excitation and absorption spectra of marine phytoplankton: I. Taxonomic characteristics and responses to photoadaptation,” J. Plankton Res. 8, 197–214 (1986).
[CrossRef]

Menzel, D. W.

C. S. Yentsch, D. W. Menzel, “A method for the determination of phytoplankton chlorophyll and phaeophytin by fluorescence,” Deep Sea Res. 10, 221–231 (1963).

Mervis, J.

Mitchell, B. G.

R. Iturriaga, B. G. Mitchell, D. A. Kiefer, “Microphotometric analysis of individual particle absorption spectra,” Limnol. Oceanogr. 33, 128–135 (1988).
[CrossRef]

Morel, A.

D. Stramski, A. Morel, “Optical properties of photosynthetic picoplankton in different physiological states as affected by growth irradiance,” Deep Sea Res. 37, 245–266 (1990).
[CrossRef]

A. Bricaud, A. Morel, “Light attenuation and scattering by phytoplanktonic cells: a theoretical modeling,” Appl. Opt. 25, 571–580 (1986).
[CrossRef] [PubMed]

A. Morel, “Optics of marine particles and marine optics,” in Particle Analysis in Oceanography, S. Demers, ed. (Springer-Verlag, Berlin, 1991), pp. 141–188.
[CrossRef]

Moum, J. N.

R. A. Desiderio, T. J. Cowles, J. N. Moum, M. Myrick, “Microstructure profiles of laser-induced chlorophyll fluorescence spectra: evaluation of backscatter and forward-scatter fiber-optic sensors,” J. Atmos. Oceanic Technol. 10, 209–224 (1993).
[CrossRef]

T. J. Cowles, J. N. Moum, R. A. Desiderio, S. M. Angel, “In situ monitoring of ocean chorophyll via laser-induced fluorescence backscattering through an optical fiber,” Appl. Opt. 28, 595–600 (1989).
[CrossRef] [PubMed]

Muirhead, K.

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

Myrick, M.

R. A. Desiderio, T. J. Cowles, J. N. Moum, M. Myrick, “Microstructure profiles of laser-induced chlorophyll fluorescence spectra: evaluation of backscatter and forward-scatter fiber-optic sensors,” J. Atmos. Oceanic Technol. 10, 209–224 (1993).
[CrossRef]

Myrick, M. L.

Neuer, S.

T. J. Cowles, R. A. Desiderio, S. Neuer, “In situ characterization of phytoplankton from vertical profiles of fluorescence emission spectra,” Mar. Biol. 115, 217–222 (1993).
[CrossRef]

Ohyumi, M.

Ord, T.

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

Owens, T. G.

T. G. Owens, “Energy transformations and fluorescence in photosynthesis,” in Particle Analysis in Oceanography, S. Demers, ed. (Springer-Verlag, Berlin, 1991), pp. 101–137.
[CrossRef]

Phinney, D. A.

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

C. S. Yentsch, D. A. Phinney, “Spectral fluorescence: an ataxonomic tool for studying the structure of phytoplankton populations,” J. Plankton Res. 7, 617–632 (1985).
[CrossRef]

C. S. Yentsch, D. A. Phinney, “Fluorescence spectral signatures for studies of marine phytoplankton,” in Mapping Strategies in Chemical Oceanography, A. Zirino, ed. (American Chemical Society, Washington, D.C., 1985).
[CrossRef]

Prentiss, M.

Salzman, G. C.

Sato, S.

Shibata, H.

Siegel, D. A.

R. Iturriaga, D. A. Siegel, “Microphotometric characterization of phytoplankton and detrital absorption properties in the Sargasso Sea,” Limnol. Oceanogr. 34, 1706–1726 (1989).
[CrossRef]

Smith, M. J.

Sonek, G. J.

E. R. Lyons, G. J. Sonek, “Confinement and bistability in a tapered hemispherically lensed optical fiber trap,” Appl. Phys. Lett. 66, 1584–1586 (1995).
[CrossRef]

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
[CrossRef]

W. H. Wright, G. J. Sonek, M. W. Berns, “Parametric study of the forces on microspheres held by optical tweezers,” Appl. Opt. 33, 1735–1748 (1994).
[CrossRef] [PubMed]

W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).

Soohoo, J. B.

J. B. Soohoo, D. A. Kiefer, D. J. Collins, I. S. McDermid, “In vivo fluorescence excitation and absorption spectra of marine phytoplankton: I. Taxonomic characteristics and responses to photoadaptation,” J. Plankton Res. 8, 197–214 (1986).
[CrossRef]

Spinrad, R. W.

Stewart, C. C.

Stramski, D.

D. Stramski, A. Morel, “Optical properties of photosynthetic picoplankton in different physiological states as affected by growth irradiance,” Deep Sea Res. 37, 245–266 (1990).
[CrossRef]

Svoboda, K.

K. Svoboda, S. M. Block, “Biological applications of optical forces,” Ann. Rev. Biophys. Biomol. Struct. 23, 247–285 (1994).
[CrossRef]

Tadir, Y.

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

Tromberg, B. J.

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

Vafa, O.

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

Vorobjev, I. A.

I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
[CrossRef] [PubMed]

Wang, W.

W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).

Waterbury, J. M.

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

Wolf, E.

M. Born, E. Wolf, Principles of Optics (Pergamon, Oxford, 1987), Sec. 13.5.1.

Wood, A. M.

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

Wright, W. H.

W. H. Wright, G. J. Sonek, M. W. Berns, “Parametric study of the forces on microspheres held by optical tweezers,” Appl. Opt. 33, 1735–1748 (1994).
[CrossRef] [PubMed]

I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
[CrossRef] [PubMed]

H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
[CrossRef] [PubMed]

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

Yamane, T. M.

A. Ashkin, J. M. Dziedzic, T. M. Yamane, “Optical trapping and manipulation of single cells using infrared laser beams,” Nature 330, 769–771 (1987).
[CrossRef] [PubMed]

Yentsch, C. M.

S. G. Ackleson, R. W. Spinrad, C. M. Yentsch, J. Brown, W. Korjeff-Bellows, “Phytoplankton optical properties: flow cytometric examinations of dilution-induced effects,” Appl. Opt. 27, 1262–1269 (1988).
[CrossRef] [PubMed]

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

Yentsch, C. S.

C. S. Yentsch, D. A. Phinney, “Spectral fluorescence: an ataxonomic tool for studying the structure of phytoplankton populations,” J. Plankton Res. 7, 617–632 (1985).
[CrossRef]

C. S. Yentsch, D. W. Menzel, “A method for the determination of phytoplankton chlorophyll and phaeophytin by fluorescence,” Deep Sea Res. 10, 221–231 (1963).

C. S. Yentsch, D. A. Phinney, “Fluorescence spectral signatures for studies of marine phytoplankton,” in Mapping Strategies in Chemical Oceanography, A. Zirino, ed. (American Chemical Society, Washington, D.C., 1985).
[CrossRef]

Zaneveld, J. R. V.

J. R. V. Zaneveld, “An asymptotic closure theory for irradiance in the sea and its inversion to obtain the inherent optical properties,” Limnol. Oceanogr. 34, 1442–1452 (1989).
[CrossRef]

Zarinetchi, F.

Ann. Rev. Biophys. Biomol. Struct.

K. Svoboda, S. M. Block, “Biological applications of optical forces,” Ann. Rev. Biophys. Biomol. Struct. 23, 247–285 (1994).
[CrossRef]

Appl. Opt.

R. W. Spinrad, J. F. Brown, “Relative real refractive index of marine microorganisms: a technique for flow cytometric estimation,” Appl. Opt. 25, 1930–1934 (1986).
[CrossRef] [PubMed]

T. N. Buican, M. J. Smith, H. A. Crissman, G. C. Salzman, C. C. Stewart, J. C. Martin, “Automated single-cell manipulation and sorting by light trapping,” Appl. Opt. 26, 5311–5316 (1987).
[CrossRef] [PubMed]

S. G. Ackleson, R. W. Spinrad, C. M. Yentsch, J. Brown, W. Korjeff-Bellows, “Phytoplankton optical properties: flow cytometric examinations of dilution-induced effects,” Appl. Opt. 27, 1262–1269 (1988).
[CrossRef] [PubMed]

S. G. Ackleson, R. W. Spinrad, “Size and refractive index of individual marine particulates: a flow cytometric approach,” Appl. Opt. 27, 1270–1277 (1988).
[CrossRef] [PubMed]

T. J. Cowles, J. N. Moum, R. A. Desiderio, S. M. Angel, “In situ monitoring of ocean chorophyll via laser-induced fluorescence backscattering through an optical fiber,” Appl. Opt. 28, 595–600 (1989).
[CrossRef] [PubMed]

M. L. Myrick, S. M. Angel, R. Desiderio, “Comparison of some fiber optic configurations for measurement of luminescence and Raman scattering,” Appl. Opt. 29, 1333–1344 (1990).
[CrossRef] [PubMed]

W. H. Wright, G. J. Sonek, M. W. Berns, “Parametric study of the forces on microspheres held by optical tweezers,” Appl. Opt. 33, 1735–1748 (1994).
[CrossRef] [PubMed]

A. Bricaud, A. Morel, “Light attenuation and scattering by phytoplanktonic cells: a theoretical modeling,” Appl. Opt. 25, 571–580 (1986).
[CrossRef] [PubMed]

Appl. Phys. Lett.

E. R. Lyons, G. J. Sonek, “Confinement and bistability in a tapered hemispherically lensed optical fiber trap,” Appl. Phys. Lett. 66, 1584–1586 (1995).
[CrossRef]

Biophys. J.

I. A. Vorobjev, H. Liang, W. H. Wright, M. W. Berns, “Optical trapping for chromosome manipulation: a wavelength dependence of induced chromosome bridges,” Biophys. J. 64, 533–538 (1993).
[CrossRef] [PubMed]

Y. Liu, D. K. Cheng, G. J. Sonek, M. W. Berns, C. F. Chapman, B. J. Tromberg, “Evidence for localized cell heating induced by infrared optical tweezers,” Biophys. J. 68, 2137–2144 (1995).
[CrossRef] [PubMed]

Deep Sea Res.

D. Stramski, A. Morel, “Optical properties of photosynthetic picoplankton in different physiological states as affected by growth irradiance,” Deep Sea Res. 37, 245–266 (1990).
[CrossRef]

C. S. Yentsch, D. W. Menzel, “A method for the determination of phytoplankton chlorophyll and phaeophytin by fluorescence,” Deep Sea Res. 10, 221–231 (1963).

Exp. Cell Res.

H. Liang, W. H. Wright, W. He, M. W. Berns, “Micromanipulation of mitotic chromosomes in PTK2 cells using laser-induced optical forces (“optical tweezers”),” Exp. Cell Res. 197, 21–35 (1991).
[CrossRef] [PubMed]

Fertility Sterility

Y. Tadir, W. H. Wright, O. Vafa, T. Ord, R. H. Asch, M. W. Berns, “Micromanipulation of sperm by a laser generated optical trap,” Fertility Sterility 52, 870–875 (1989).

IEEE Photon. Technol. Lett.

G. J. Escandon, Y. Liu, G. J. Sonek, M. W. Berns, “Beam magnification and the efficiency of optical trapping with 90-nm AlGaAs laser diodes,” IEEE Photon. Technol. Lett. 6, 597–600 (1994).
[CrossRef]

J. Atmos. Oceanic Technol.

R. A. Desiderio, T. J. Cowles, J. N. Moum, M. Myrick, “Microstructure profiles of laser-induced chlorophyll fluorescence spectra: evaluation of backscatter and forward-scatter fiber-optic sensors,” J. Atmos. Oceanic Technol. 10, 209–224 (1993).
[CrossRef]

J. Plankton Res.

C. S. Yentsch, D. A. Phinney, “Spectral fluorescence: an ataxonomic tool for studying the structure of phytoplankton populations,” J. Plankton Res. 7, 617–632 (1985).
[CrossRef]

J. B. Soohoo, D. A. Kiefer, D. J. Collins, I. S. McDermid, “In vivo fluorescence excitation and absorption spectra of marine phytoplankton: I. Taxonomic characteristics and responses to photoadaptation,” J. Plankton Res. 8, 197–214 (1986).
[CrossRef]

Limnol. Oceanogr.

R. Iturriaga, B. G. Mitchell, D. A. Kiefer, “Microphotometric analysis of individual particle absorption spectra,” Limnol. Oceanogr. 33, 128–135 (1988).
[CrossRef]

R. Iturriaga, D. A. Siegel, “Microphotometric characterization of phytoplankton and detrital absorption properties in the Sargasso Sea,” Limnol. Oceanogr. 34, 1706–1726 (1989).
[CrossRef]

L. Campbell, R. H. Iturriaga, “Identification of Synechococcus spp. in the Sargasso Sea by immunofluorescence and fluorescence excitation spectroscopy performed on individual cells,” Limnol. Oceanogr. 35, 1196–1201 (1988).
[CrossRef]

A. M. Wood, P. K. Horan, K. Muirhead, D. A. Phinney, C. M. Yentsch, J. M. Waterbury, “Discrimination between types of pigments in marine Synechococcus spp. by scanning spectroscopy, epifluorescence microscopy, and flow cytometry,” Limnol. Oceanogr. 30, 1303–1315 (1985).
[CrossRef]

J. R. V. Zaneveld, “An asymptotic closure theory for irradiance in the sea and its inversion to obtain the inherent optical properties,” Limnol. Oceanogr. 34, 1442–1452 (1989).
[CrossRef]

Mar. Biol.

T. J. Cowles, R. A. Desiderio, S. Neuer, “In situ characterization of phytoplankton from vertical profiles of fluorescence emission spectra,” Mar. Biol. 115, 217–222 (1993).
[CrossRef]

Nature

A. Ashkin, J. M. Dziedzic, T. M. Yamane, “Optical trapping and manipulation of single cells using infrared laser beams,” Nature 330, 769–771 (1987).
[CrossRef] [PubMed]

Oceanogr.

T. J. Cowles, R. A. Desiderio, “Resolution of biological microstructure through in situ fluorescence emission spectra,” Oceanogr. 6, 105–111 (1993).

Opt. Lett.

Other

C. S. Yentsch, D. A. Phinney, “Fluorescence spectral signatures for studies of marine phytoplankton,” in Mapping Strategies in Chemical Oceanography, A. Zirino, ed. (American Chemical Society, Washington, D.C., 1985).
[CrossRef]

S. L. Bower, R. Iturriaga, “Preparation of natural phytoplankton communities to preserve spectral fluorescence properties,” in Ocean Optics XI, G. D. Gilbert, ed., Proc. Soc. Photo-Opt. Instrum. Eng.1750, 224–232 (1992).

T. G. Owens, “Energy transformations and fluorescence in photosynthesis,” in Particle Analysis in Oceanography, S. Demers, ed. (Springer-Verlag, Berlin, 1991), pp. 101–137.
[CrossRef]

R. R. L. Guillard, “Culture of phytoplankton for feeding marine invertebrates,” in Culture of Marine Invertebrate Animals, W. L. Smith, M. H. Chanley, eds. (Plenum, New York, 1975), pp. 29–60.
[CrossRef]

M. Born, E. Wolf, Principles of Optics (Pergamon, Oxford, 1987), Sec. 13.5.1.

C. F. Bohren, D. R. Huffman, Absorption and Scattering of Light by Small Particles (Wiley, New York, 1983).

A. Morel, “Optics of marine particles and marine optics,” in Particle Analysis in Oceanography, S. Demers, ed. (Springer-Verlag, Berlin, 1991), pp. 141–188.
[CrossRef]

S. Demers, ed., Particle Analysis in Oceanography (Springer-Verlag, Berlin, 1991).
[CrossRef]

W. Wang, Y. Liu, G. J. Sonek, M. W. Berns, R. A. Keller, “Optical trapping and fluorescence detection in laminar flow streams,” Appl. Phys. Lett. (to be published).

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Figures (11)

Fig. 1
Fig. 1

(a) Experimental system for marine microparticle analysis with fluorescence-based optical tweezers. Components include S’s, shutters; λ/2, half-wave plate; POL, polarizer; NBF, narrow-band filter; NDF, neutral-density filter; L1–L4, lenses; DBS1 and DBS2, dichroic beam splitters; PH, pinhole; TC, temperature controller; SC, sample chamber; MO, microscope objective; M1 and M2, mirrors; DG, diffraction grating; CCD, detector array; PC, personal computer; (b) expanded view of a spherical particle held stationary by a focused Gaussian laser beam while fluorescence is excited and detected; (c) geometry and coordinate system used for backscattering measurements. θ and φ are polar and azimuthal angles, and the scattering angle is defined as ψ = 180 – θ°. k i and k s are wave vectors for incident and scattered beams, respectively.

Fig. 2
Fig. 2

Expanded view of a Rose chamber, and the method for changing the sample medium.

Fig. 3
Fig. 3

Relative spectrophotometric plots for Nannochloris and Synechococcus phytoplankton cells. The curves help identify key pigment absorption wavelengths but do not account for undetected scattering effects during spectrophotometric measurements.

Fig. 4
Fig. 4

Bulk fluorescence signals for Nannochloris and Synechococcus, measured with a low-power (40×) magnification objective. If normalized by the number of cells, a single mean cell of the population could be represented.

Fig. 5
Fig. 5

Comparison of fluorescence signals from five different optically trapped Nannochloris cells. Samples were exposed to UV excitation for 0.1 s at a power density of 10 μW/cm2.

Fig. 6
Fig. 6

Dependence of Nannochloris fluorescence-emission intensity on UV-exposure time, measured at the peak emission wavelength of 680 nm (Chl a).

Fig. 7
Fig. 7

Fluorescence intensity as a function of applied laser trapping power. Measurements were made at the fluorescence-emission wavelength of 680 nm, and for UV- and IR-exposure times of 0.1 s and 10 s, respectively.

Fig. 8
Fig. 8

Intensity of fluorescence for four different Synechococcus cells, each confined by optical tweezers at a power level of 10 mW and at a slightly different time.

Fig. 9
Fig. 9

Time-dependent fluorescence from a single Syncechococcus cell, confined by the tweezers for more than 5 hr, with fluorescence emission sampled every hour.

Fig. 10
Fig. 10

Backscattering signals from two different, individually trapped Nannochloris cells, (a) cell A and (b) cell B, measured at a wavelength of 632.8 nm. For each cell, four separate backscatter measurements were made by releasing the cell from the trap and then recapturing it several seconds later. Measurements are made as a function of scattering angle ψ in the azimuthal plane φ = 90° and a polarization parallel to the plane of incidence.

Fig. 11
Fig. 11

Angular backscatter intensities for(a) an optically trapped, 3-μm-diameter, latex microsphere with a relative refractive index of 1.18 measured at 632.8 nm, and (b) Mie-theory results for I 1 and I 2, calculated for the parameters α = 19.809 and ρ = 7.131.

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