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Review of optical tweezers in vacuum

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Frontiers of Information Technology & Electronic Engineering 2019年第5期20卷 655-673页

作者： Nan LI Xun-min ZHU Wen-qiang LI Zhen-hai FU Meng-zhu HU Hui-zhu HU State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang University Hangzhou 310027 China

As a versatile tool for trapping and manipulating neutral particles, optical tweezers have been studied in a broad range of fields such as molecular biology, nanotechnology, and experimentally physics since Arthur Ashkin pioneered the field in the early 1970 s. By levitating the "sensor" with a laser beam instead of adhering it to solid components, excellent environmental decoupling is achieved. Furthermore, unlike levitating particles in liquid or air, optical tweezers operating in vacuum are isolated from environmental thermal noise, thus eliminating the primary source of dissipation present for most inertial sensors. This attracted great attention in both fundamental and applied physics. In this paper we review the history and the basic concepts of optical tweezers in vacuum and provide an overall understanding of the field.

关键词： Optical tweezers Optical trapping in vacuum Optical cooling

Holographic Raman tweezers Controlled by Hand Gestures and Voice Commands

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Optics and Photonics Journal 2013年第2期3卷 331-336页

作者： Zoltan Tomori Marian Antalik Peter Kesa Jan Kanka Petr Jakl Mojmir Sery Silvie Bernatova Pavel Zemanek 1Department of Biophysics Institute of Experimental Physics SAS Kosice Slovakia 2Department of Biochemistry P. J. Safarik University Kosice Slovakia Department of Biochemistry P. J. Safarik University Kosice Slovakia Department of Biophysics Institute of Experimental Physics SAS Kosice Slovakia Institute of Scientific Instruments of the ASCR v.v.i. Brno Czech Republic

Several attempts have appeared recently to control optical trapping systems via touch tablets and cameras instead of a mouse and joystick. Our approach is based on a modern low-cost hardware combined with fingertips and speech recognition software. Positions of operator's hands or fingertips control the positions of trapping beams in holographic optical tweezers that provide optical manipulation with microobjects. We tested and adapted two systems for hands position detection and gestures recognition – Creative Interactive Gesture Camera and Leap Motion. We further enhanced the system of Holographic Raman tweezers (HRT) by voice commands controlling the micropositioning stage and acquisition of Raman spectra. Interface communicates with HRT either directly by which requires adaptation of HRT firmware, or indirectly by simulating mouse and keyboard messages. Its utilization in real experiments speeded up the operator’s communication with the system cca. Two times in comparison with the traditional control by the mouse and the keyboard.

关键词： Holographic Optical tweezers Raman tweezers Natural User Interface Leap Motion Gesture Camera

Dynamics Study of the Deformation of Red Blood Cell by Optical tweezers

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Open Journal of Biophysics 2017年第2期7卷 59-69页

作者： Konin E. Jean Michel Yale Pavel Megnassan Eugene Michel A. Kouacou Jeremie T. Zoueu Laboratoire d’Instrumentation Image et Spectroscopie UMRI EEA INP-HB Yamoussoukro Cote d’Ivoire Laboratoire de Physique Fondamentale et Appliquée UNA Abidjan Cote d’Ivoire

In recent years, extensive research has been carried out on red blood cells in order to investigate their mechanical properties. The interest in these studies has been possible thanks to the technological innovations made in the field of micro or nano manipulation of biological and non-biological particles without physical contact. In the present project, we have developed a new approach to study the deformation of red blood cells moving against a trapped microbead by applying a sinusoidal voltage (DC offset 3.5 Vpp) to the stage at 0.4 Hz frequencies. The oscillating movement imposed on the stage highlights the indentation test and the tensile test known for the study of mechanical behavior of materials. The mechanical properties found are: the modulus of elasticity (Young Modulus), the shear modulus, the coefficient of hardening and erythrocyte resistance coefficient. The axial shear modulus 25.00 ± 1.5 μN/m and the transversal shear modulus 15.7 ± 4.63 μN/m were compared to those in the literature. These values were respectively determined by Hooke’s law and the Hertz model.

关键词： Optical tweezers Elasticity Mechanical Properties Tensile Indentation

Ultrasound tweezers Trigger Single-Cell Mechanical Dynamics for Cell Mechanophenotyping

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医用生物力学 2019年第A1期34卷 46-46页

作者： Weiyi Qian Apratim Bajpai Jie Tong Zijing Zhang Weiqiang Chen Department of Mechanical and Aerospace Engineering New York University

Cells actively modulate mechanobiological circuitry against external perturbations to stabilize whole cell/tissue *** dynamic adaption of cells to mechanical force is critical for cells to perform vital biological functions,from single cell migration to embryonic *** of such dynamics has been associated with pathophysiological conditions in cardiovascular diseases,cancer,aging,and developmental disorders[1].Therefore,a direct understanding of cell’s biomechanical adaptive/maladaptive behaviors and the trigger factors causing the transformation of healthy adaption to maladaptation can help reveal the regulatory role of single cell mechanosensitive dynamics in the progression of various degenerative diseases and ***,current efforts for uncovering fundamental associations between disease and cell architecture have been focusing on'static'measurements of biophysical properties,which is limited by the requirement of large sample sizes to obtain statistically significant *** therefore developed a single and highly integrated platform with mechanical stimulation and fine spatiotemporal sensing functions to probe the single cell mechanical dynamics at subcellular level to determine cell’s mechanophenotypes in healthy and disease *** developed an integrated micromechanical system composed of an’ultrasound tweezer’stimulator[2]and a PDMS micropillar array [3] cellular force sensor to in situ noninvasively probe and monitor single cell mechanical *** smooth muscle cells(VSMCs)from healthy mouse and mouse with induced abdominal aorta aneurysm(AAA)were used for cell mechanobiological *** ultrasound transducer(V312-SM,Olympus)was used to generate ultrasound pulses to excite lipid-encapsulated microbubbles(Targeson)binding to cell membrane through an RGD-integrin linkage to apply a transient nanonewton force to VSMCs seeded on the PDMS micropillar *** micropillar array was fabricated and functionali

关键词： AAA Ultrasound tweezers Trigger Single-Cell Mechanical Dynamics Cell Mechanophenotyping

Determination of liquid viscosity based on dual-frequency-bandparticle tracking

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Chinese Physics B 2024年第9期33卷 359-364页

作者： Lihua Yan Boyin Xue Yuanji Li Jinxia Feng Xingkang Wu Kuanshou Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006China

An optical-tweezers-based dual-frequency-band particle tracking system was designed and fabricated for liquid viscositydetection. On the basis of the liquid viscosity dependent model of the particle’s restricted Brownian motion with theFax´en correction taken into account, the liquid viscosity and optical trap stiffness were determined by fitting the theoreticalprediction with the measured power spectral densities of the particle’s displacement and velocity that were derived from thedual-frequency-band particle tracking data. When the SiO2 beads were employed as probe particles in the measurements ofdifferent kinds of liquids, the measurement results exhibit a good agreement with the reported results, as well as a detectionuncertainty better than 4.6%. This kind of noninvasive economical technique can be applied in diverse environments forboth in situ and ex situ viscosity detection of liquids.

关键词： liquid viscosity optical tweezers dual-frequency-band particle tracking power spectral density

Trapping and Driving Individual Charged Micro-particles in Fluid with an Electrostatic Device

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Nano-Micro Letters 2016年第3期8卷 270-281页

作者： Jingjing Xu Zijing Lei Jingkun Guo Jie Huang Wei Wang Uta Reibetanz Shengyong Xu Key Laboratory for the Physics & Chemistry of Nanodevices and Department of Electronics Peking University Institute of Microelectronics Peking University Medical Faculty Institute for Medical Physics and Biophysics University of Leipzig

A variety of micro-tweezers techniques, such as optical tweezers, magnetic tweezers, and dielectrophoresis technique, have been applied intensively in precise characterization of micro/nanoparticles and bio-molecules. They have contributed remarkably in better understanding of working mechanisms of individual sub-cell organelles, proteins, and DNA. In this paper, we present a controllable electrostatic device embedded in a microchannel, which is capable of driving,trapping, and releasing charged micro-particles suspended in microfluid, demonstrating the basic concepts of electrostatic tweezers. Such a device is scalable to smaller size and offers an alternative to currently used micro-tweezers for application in sorting, selecting, manipulating, and analyzing individual micro/nanoparticles. Furthermore, the system offers the potential in being combined with dielectrophoresis and other techniques to create hybrid micro-manipulation systems.

关键词： Electrostatic tweezers Charged particles Coulomb potential well Manipulation Trap

Direct Observation of Histone-Induced DNA Shortening

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Chinese Physics Letters 2006年第2期23卷 504-507页

作者：冉诗勇王晓玲付文博赖振华王渭池刘晓晴麦振洪李明 Belting National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 Life Science College Capital Normal University Beijjng 100037

We construct a system of magnetic tweezers and apply it to study the interaction between histones and DNA. The condensation of DNA by purified histones at low ionic strengths is directly monitored by recording the length of the DNA as a function of elapsed time. It is found that DNA condensates in a dynamic manner. The binding of hist, ones to DNA is energetically favoured, but the ten,sion applied on DNA tends to unravel the DNA-histone complex, The competition between the two processes determiners the rate of the DNA condensation.

关键词： SINGLE CHROMATIN FIBERS SUPERCOILED DNA RNA-POLYMERASE STRANDED-DNA MOLECULES ELASTICITY FORCE NUCLEOSOMES RESOLUTION tweezers

Recent progress on the design and fabrication of micromotors and their biomedical applications

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Bio-Design and Manufacturing 2018年第4期1卷 225-236页

作者： Wensen Jiangl Liang Ma Xiaobin Xul School of Materials Science and Engineering Tongji UniversityShanghai 201804China State Key Laboratory of Fluid Power and Mechatronic Systems &School of Mechanical Engineering Zhejiang UniversityHangzhou 310058China

The advancement in the micro-/nanofabrication techniques has greatly facilitated the development of micromotors.A variety of micromotors have been invented with powerful functions,which have attracted a broad range of interests from chemistry, physics,mechanics,biology and *** this paper,we reviewed recent progress in micromotors and highlighted representative *** mechanisms of micromotors by internal and external energy sources were *** described general fabrication strategies of the popular micromotors (wire,tubular,helical and Janus)including bottom-up and top-down *** the application section,we primarily focused on the biological applications,such as biological cargo delivery, biosensing and *** last,we discussed the current challenges and provided future prospects.

关键词： Micromotor Nanomotor Electric tweezers Drug delivery Nanorobot Micromachine

Controlling the Flow of Microscopic Particles—The Role of Beam Size

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Optics and Photonics Journal 2012年第4期2卷 294-299页

作者： Jitendra Bhatt Ashok Kumar Saiyed Nisar Ali Jaaffrey Ravindra Pratap Singh Department of Physics University College of Science Mohan Lal Sukhadia University Udaipur India Theoretical Physics Division Physical Research Laboratory Ahmedabad India

Flow of micro particles and fluids is important in many microscopic systems. Here we present details of our finding of a directional flow of micro particles due to a single beam optical trap. It was found that the directional flow depends upon the size of optical trap, the number density of particles in the solution and the time after the trap was created. We suggest controlling the motion of microscopic particles in a fluid by varying a simple parameter like beam size for microfluidics applications.

关键词： Optical Manipulation Optical tweezers Directional Flow