Optimal optical trap for bacterial viability.

Optical trapping is a powerful tool for the micromanipulation of living cells--especially bacteria--but photodamage induced by the laser beam can adversely affect viability. We have explored optical trapping conditions in the near infrared (840-930 nm) that preserve the viability of E. coli, as measured by gene expression of green fluorescent protein. We have found that time-sharing the optical traps, i.e., dwelling only 10 micros-1 ms on the cell, improves viability relative to continuous wave (CW) exposure for the same exposure time. We have also observed that similar to CW traps the photodamage in a time-shared trap depends weakly on wavelength, but linearly on peak power, implying an effect induced by single photon absorption. Taken altogether, integrating the exposure time and peak power, the data indicate that there is a lethal energy dose of about 5 J for E. coli. Thus a single parameter--the energy--can be used to describe the limitation on viability.

[1]  Arthur Ashkin,et al.  Optical Levitation by Radiation Pressure , 1971 .

[2]  K Bergman,et al.  Characterization of photodamage to Escherichia coli in optical traps. , 1999, Biophysical journal.

[3]  P. Matsudaira,et al.  Laser-guided assembly of heterotypic three-dimensional living cell microarrays. , 2006, Biophysical journal.

[4]  Fumihito Arai,et al.  Synchronized laser micromanipulation of multiple targets along each trajectory by single laser , 2004 .

[5]  T Feurer,et al.  Two‐photon excitation and emission spectra of the green fluorescent protein variants ECFP, EGFP and EYFP , 2005, Journal of microscopy.

[6]  D. Grier.  A revolution in optical manipulation , 2003, Nature.

[7]  Ove Axner,et al.  Stress response in Caenorhabditis elegans caused by optical tweezers: wavelength, power, and time dependence. , 2002, Biophysical journal.

[8]  M W Berns,et al.  Effects of ultraviolet exposure and near infrared laser tweezers on human spermatozoa. , 1996, Human reproduction.

[9]  Robert L Sah,et al.  Probing the role of multicellular organization in three-dimensional microenvironments , 2006, Nature Methods.

[10]  O. Axner,et al.  Design for fully steerable dual-trap optical tweezers. , 1997, Applied optics.

[11]  S. Block,et al.  Construction of multiple-beam optical traps with nanometer-resolution position sensing , 1996 .

[12]  Miles J. Padgett,et al.  Permanent 3D microstructures in a polymeric host created using holographic optical tweezers , 2004 .

[13]  L. Oddershede,et al.  Optical Tweezers Cause Physiological Damage to Escherichia coli and Listeria Bacteria , 2008, Applied and Environmental Microbiology.

[14]  Victor A. Soifer,et al.  Iteractive Methods For Diffractive Optical Elements Computation , 1997 .

[15]  M W Berns,et al.  Laser-induced multiphoton processes in living cells. , 1983, Proceedings of the National Academy of Sciences of the United States of America.

[16]  Yael Roichman,et al.  Optimized holographic optical traps. , 2005, Optics express.

[17]  D. Hanstorp,et al.  Sorting Out Bacterial Viability with Optical Tweezers , 2000, Journal of bacteriology.

[18]  K. Schütze,et al.  Force generation of organelle transport measured in vivo by an infrared laser trap , 1990, Nature.

[19]  Bernhard O Palsson,et al.  Optoinjection for efficient targeted delivery of a broad range of compounds and macromolecules into diverse cell types. , 2006, Journal of biomedical optics.

[20]  Mattias Goksör,et al.  Creating permanent 3D arrangements of isolated cells using holographic optical tweezers. , 2005, Lab on a chip.

[21]  Dudley A. Williams,et al.  Optical properties of water in the near infrared. , 1974 .

[22]  A. Ashkin,et al.  Optical trapping and manipulation of viruses and bacteria. , 1987, Science.

[23]  M W Berns,et al.  Physiological monitoring of optically trapped cells: assessing the effects of confinement by 1064-nm laser tweezers using microfluorometry. , 1996, Biophysical journal.

[24]  A. Ashkin.  Forces of a single-beam gradient laser trap on a dielectric sphere in the ray optics regime. , 1992, Methods in cell biology.

[25]  J. Hubbell,et al.  Characterization of permeability and network structure of interfacially photopolymerized poly(ethylene glycol) diacrylate hydrogels. , 1998, Biomaterials.

[26]  S J Bryant,et al.  Cytocompatibility of UV and visible light photoinitiating systems on cultured NIH/3T3 fibroblasts in vitro , 2000, Journal of biomaterials science. Polymer edition.

[27]  Gregory B. Altshuler,et al.  Investigation of IR absorption spectra of oral cavity bacteria , 1996, European Conference on Biomedical Optics.

[28]  A. Ashkin,et al.  Optical trapping and manipulation of single cells using infrared laser beams , 1987, Nature.

[29]  M. Prausnitz,et al.  Intracellular Drug Delivery Using Low-Frequency Ultrasound: Quantification of Molecular Uptake and Cell Viability , 2001, Pharmaceutical Research.

[30]  Jennifer E. Curtis,et al.  Dynamic holographic optical tweezers , 2002 .

[31]  K. König,et al.  Cell damage by near-IR microbeams , 1995, Nature.

[32]  Shimshon Belkin,et al.  Advances in preservation methods: keeping biosensor microorganisms alive and active. , 2006, Current opinion in biotechnology.

[33]  J. Molloy,et al.  Optical chopsticks: digital synthesis of multiple optical traps. , 1998, Methods in cell biology.

[34]  Sangeeta N Bhatia,et al.  Multiphase electropatterning of cells and biomaterials. , 2007, Lab on a chip.

[35]  M W Berns,et al.  A possible two-photon effect in vitro using a focused laser beam. , 1976, Biophysical journal.

[36]  Kytai Truong Nguyen,et al.  Photopolymerizable hydrogels for tissue engineering applications. , 2002, Biomaterials.

[37]  B. Tromberg,et al.  Cell damage in near-infrared multimode optical traps as a result of multiphoton absorption. , 1996, Optics letters.

[38]  Jinseok Heo,et al.  A microfluidic bioreactor based on hydrogel-entrapped E. coli: cell viability, lysis, and intracellular enzyme reactions. , 2003, Analytical chemistry.