Micro-Dumbbells—A Versatile Tool for Optical Tweezers

Manipulation of micro- and nano-sized objects with optical tweezers is a well established, albeit still evolving technique. While many objects can be trapped directly with focused laser beam(s), for some applications indirect manipulation with tweezers-operated tools is preferred. We introduce a simple, versatile micro-tool operated with holographic optical tweezers. The 40 µm long dumbbell-shaped tool, fabricated with two-photon laser 3D photolithography has two beads for efficient optical trapping and a probing spike on one end. We demonstrate fluids viscosity measurements and vibration detection as examples of possible applications.

Download Full-text

Optical trapping with non-diffracting Airy beams array using a holographic optical tweezers

Optics & Laser Technology ◽

10.1016/j.optlastec.2020.106678 ◽

2021 ◽

Vol 135 ◽

pp. 106678

Author(s):

Rafael A.B. Suarez ◽

Antonio A.R. Neves ◽

Marcos R.R. Gesualdi

Keyword(s):

Optical Tweezers ◽

Optical Trapping ◽

Holographic Optical Tweezers ◽

Airy Beams

Download Full-text

Red blood cell in the field of a beam of optical tweezers

Quantum Electronics ◽

10.1070/qel17962 ◽

2022 ◽

Vol 52 (1) ◽

pp. 22-27

Author(s):

P B Ermolinskiy ◽

A E Lugovtsov ◽

A N Semenov ◽

A V Priezzhev

Keyword(s):

Blood Cell ◽

Laser Beam ◽

Red Blood Cells ◽

Optical Tweezers ◽

Red Blood Cell ◽

Blood Cells ◽

Optical Trapping ◽

Optical Trap ◽

Beam Power ◽

Deformation Properties

Abstract We consider the effect of a tightly focused laser beam with a wavelength of 1064 nm and a power from 10 to 160 mW on red blood cells during their optical trapping with optical tweezers. It is found that the shape of a red blood cell, which alters after optical trapping, ceases to change when the trapping duration is less than 5 min and the laser beam power is less than 60 mW. At a beam power above 80 mW, the red blood cell begins to fold at a trapping duration of about 1 min, and at powers above 100-150 mW, the red blood cell membrane ruptures in 1-3 min after optical trapping. It is also found that with repeated short-term capture of a red blood cell in an optical trap, the deformation properties of the membrane change: it becomes more rigid. The obtained results are important both for understanding the mechanisms of interaction of a laser beam with red blood cells and for optimising the technique of optical experiments, especially for measuring the deformation properties of a membrane using optical tweezers.

Download Full-text

Optically Driven Micromanipulation Tools Fabricated by Two-photon Microstereolithography

MRS Proceedings ◽

10.1557/proc-739-h9.4 ◽

2002 ◽

Vol 739 ◽

Author(s):

Shoji Maruo ◽

Koji Ikuta ◽

Hayato Korogi

Keyword(s):

Laser Beam ◽

Biological Samples ◽

Living Cell ◽

Optical Trapping ◽

Cell Protein ◽

Two Photon ◽

Focal Position ◽

Handling Method

ABSTRACTLight-driven micromanipulators have been developed by two-photon microstereolithography. The manipulators are driven and controlled by optical trapping. The torque of micromanipulator was successfully controlled on the order of femto-newton by adjusting the focal position of the trapped laser beam. Nanotweezers and a nanoneedle with probe tip of diameter 250 nm were fabricated and driven in a liquid. Such remote-controlled manipulation tools provide a unique and effective handling method of biological samples such as living cell, protein and DNA.

Download Full-text

Single-Cell Elasticity Measurement with an Optically Actuated Microrobot

Micromachines ◽

10.3390/mi11090882 ◽

2020 ◽

Vol 11 (9) ◽

pp. 882

Author(s):

István Grexa ◽

Tamás Fekete ◽

Judit Molnár ◽

Kinga Molnár ◽

Gaszton Vizsnyiczai ◽

...

Keyword(s):

Optical Tweezers ◽

Target Cells ◽

Lateral Direction ◽

Two Photon ◽

Holographic Optical Tweezers ◽

Feasible Alternative ◽

A Cell ◽

Cell Elasticity ◽

Force Range ◽

Elasticity Measurement

A cell elasticity measurement method is introduced that uses polymer microtools actuated by holographic optical tweezers. The microtools were prepared with two-photon polymerization. Their shape enables the approach of the cells in any lateral direction. In the presented case, endothelial cells grown on vertical polymer walls were probed by the tools in a lateral direction. The use of specially shaped microtools prevents the target cells from photodamage that may arise during optical trapping. The position of the tools was recorded simply with video microscopy and analyzed with image processing methods. We critically compare the resulting Young’s modulus values to those in the literature obtained by other methods. The application of optical tweezers extends the force range available for cell indentations measurements down to the fN regime. Our approach demonstrates a feasible alternative to the usual vertical indentation experiments.

Download Full-text

Optical Trapping of Thermo-responsive Microgel Particles by Holographic Optical Tweezers

10.1063/1.3643549 ◽

2011 ◽

Cited By ~ 1

Author(s):

M. R. Rajesh Kannan ◽

B. V. R. Tata ◽

R. Dasgupta ◽

S. Ahlawat ◽

P. K. Gupta ◽

...

Keyword(s):

Optical Tweezers ◽

Optical Trapping ◽

Holographic Optical Tweezers ◽

Microgel Particles

Download Full-text

Optical tweezers: theory and practice

The European Physical Journal Plus ◽

10.1140/epjp/s13360-020-00843-5 ◽

2020 ◽

Vol 135 (12) ◽

Author(s):

Giuseppe Pesce ◽

Philip H. Jones ◽

Onofrio M. Maragò ◽

Giovanni Volpe

Keyword(s):

Laser Beam ◽

Optical Tweezers ◽

Dipole Approximation ◽

Theoretical Background ◽

Theory And Practice ◽

Optical Traps ◽

General Description ◽

Optical Forces ◽

Holographic Optical Tweezers ◽

Calibration Techniques

AbstractThe possibility for the manipulation of many different samples using only the light from a laser beam opened the way to a variety of experiments. The technique, known as Optical Tweezers, is nowadays employed in a multitude of applications demonstrating its relevance. Since the pioneering work of Arthur Ashkin, where he used a single strongly focused laser beam, ever more complex experimental set-ups are required in order to perform novel and challenging experiments. Here we provide a comprehensive review of the theoretical background and experimental techniques. We start by giving an overview of the theory of optical forces: first, we consider optical forces in approximated regimes when the particles are much larger (ray optics) or much smaller (dipole approximation) than the light wavelength; then, we discuss the full electromagnetic theory of optical forces with a focus on T-matrix methods. Then, we describe the important aspect of Brownian motion in optical traps and its implementation in optical tweezers simulations. Finally, we provide a general description of typical experimental setups of optical tweezers and calibration techniques with particular emphasis on holographic optical tweezers.

Download Full-text

Simultaneous printing and deformation of microsystems via two-photon lithography and holographic optical tweezers

Materials Horizons ◽

10.1039/c8mh01100a ◽

2019 ◽

Vol 6 (2) ◽

pp. 350-355 ◽

Cited By ~ 7

Author(s):

Samira Chizari ◽

Lucas A. Shaw ◽

Jonathan B. Hopkins

Keyword(s):

Optical Tweezers ◽

Strain Energy ◽

Two Photon ◽

Holographic Optical Tweezers

Microstructures with embedded strain energy are fabricated by an advanced approach that combines two-photon lithography with holographic optical tweezers.

Download Full-text

Two-photon excitation microscopy in cellular biophysics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136684 ◽

1995 ◽

Vol 53 ◽

pp. 62-63

Author(s):

David W. Piston ◽

Brian D. Bennett ◽

Robert G. Summers

Keyword(s):

Confocal Microscopy ◽

Laser Beam ◽

Duty Cycle ◽

Excited Electronic State ◽

Input Power ◽

Two Photon ◽

Simultaneous Absorption ◽

Photon Excitation ◽

Very High ◽

Two Photon Excitation

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10-5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

Download Full-text

A model of Gaussian laser beam self-trapping in optical tweezers for nonlinear particles

Optical and Quantum Electronics ◽

10.1007/s11082-021-03074-9 ◽

2021 ◽

Vol 53 (8) ◽

Author(s):

Quy Ho Quang ◽

Thanh Thai Doan ◽

Kien Bui Xuan ◽

Thang Nguyen Manh

Keyword(s):

Laser Beam ◽

Optical Tweezers ◽

Gaussian Laser Beam ◽

Self Trapping

Download Full-text

ORIENTATING MANIPULATION OF CYLINDRICAL PARTICLES WITH OPTICAL TWEEZERS

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s021886350800438x ◽

2008 ◽

Vol 17 (04) ◽

pp. 387-394 ◽

Cited By ~ 1

Author(s):

XIUDONG SUN ◽

XUECONG LI ◽

JIANLONG ZHANG

Keyword(s):

Escherichia Coli ◽

Carbon Nanotubes ◽

Laser Beam ◽

Optical Tweezers ◽

Optical Trap ◽

Polarization Direction ◽

Beam Shape ◽

E Coli ◽

Potential Applications ◽

Cylindrical Particles

Orientating manipulations of cylindrical particles were performed by optical tweezers. Vertical and horizontal manipulations of Escherichia coli (E. coli) were carried out by changing the trapping depth and the focused laser beam shape. It was found that carbon nanotubes bundles (CNTBs) could be rotated in the linear polarized optical trap until it orientated its long axis along the linear polarization direction of the laser beam. However, E.coli could not be orientated in this way. Corresponding mechanisms were discussed based on the anisomeric electric characters of CNTBs. These orientation technologies of cylindrical objects with optical trap have potential applications in assembling nano-electric devices.

Download Full-text