Stretching single DNA molecules to demonstrate high-force capabilities of holographic optical tweezers.
The well calibrated force-extension behaviour of single double-stranded DNA molecules was used as a standard to investigate the performance of phase-only holographic optical tweezers at high forces. Specifically, the characteristic overstretch transition at 65 pN was found to appear where expected, demonstrating (1) that holographic optical trap calibration using thermal fluctuation methods is valid to high forces; (2) that the holographic optical traps are harmonic out to >250 nm of 2.1 mum particle displacement; and (3) that temporal modulations in traps induced by the spatial light modulator (SLM) do not affect the ability of optical traps to hold and steer particles against high forces. These studies demonstrate a new high-force capability for holographic optical traps achievable by SLM technologies.
Department of Physics, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada.
Arnau
A
Farré
Astrid
A
van der Horst
Gerhard A
GA
Blab
Benjamin P B
BP
Downing
Nancy R
NR
Forde
D000469:Alkaline Phosphatase / Q000737:chemistry; D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D001696:Biomechanical Phenomena; D001710:Biotin / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D004076:Digoxigenin / Q000031:analogs & derivatives / Q000737:chemistry / Q000276:immunology; D019793:Fluorescein / Q000737:chemistry; D056656:Lab-On-A-Chip Devices; D008863:Microspheres; D009038:Motion; D009419:Nerve Tissue Proteins / Q000737:chemistry; D052898:Optical Tweezers; D019809:Streptavidin / Q000737:chemistry
D000906:Antibodies; C029152:G-substrate; D009419:Nerve Tissue Proteins; D001710:Biotin; D004247:DNA; D019809:Streptavidin; D000469:Alkaline Phosphatase; D004076:Digoxigenin; D019793:Fluorescein