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Holographic microscopy

Stanislaw Makarchuk, Nicolas Beyer, Christian Gaiddon, Wilfried Grange, Pascal Hébraud
Traction Force Microscopy (TFM) computes the forces exerted at the surface of an elastic material by measuring induced deformations in volume. It is used to determine the pattern of the adhesion forces exerted by cells or by cellular assemblies grown onto a soft deformable substrate. Typically, colloidal particles are dispersed in the substrate and their displacement is monitored by fluorescent microscopy. As with any other fluorescent techniques, the accuracy in measuring a particule's position is ultimately limited by the number of evaluated fluorescent photons...
February 14, 2018: Scientific Reports
Zhiyuan Shen, Yonghong He, Gong Zhang, Qinghua He, Dongmei Li, Yanhong Ji
A dual-wavelength digital holographic phase and fluorescence microscopy system is demonstrated as the decoding and detection platform of an optical thickness encoded suspension array. The phase imaging path is designed to decode optical thickness encoded microcarriers, and the fluorescence imaging path is used to detect the quantitative information of the bound target analytes. The encoding capacity could be more than 100. The decoding reliability of the phase imaging path is verified by a multiplexed immunoassay experiment...
February 15, 2018: Optics Letters
Sébastien A Lévesque, Jean-Michel Mugnes, Erik Bélanger, Pierre Marquet
Quantitative phase imaging (QPI) has recently emerged as a powerful new quantitative microscopy technique suitable for the noninvasive exploration of the structure and dynamics of transparent specimens, including living cells in culture. Indeed, the quantitative phase signal (QPS), induced by transparent living cells, can be detected with a nanometric axial sensitivity, and contains a wealth of information about both cell morphology and content. However, QPS is also sensitive to various sources of experimental noise...
February 10, 2018: Methods: a Companion to Methods in Enzymology
Xing Wang, Guang-Ming Zhang, Hongwei Ma, Yishu Zhang, Doudou Wang
In ultrasonic array imaging, 3D ultrasonic wavefields are normally recorded by an ultrasonic piezo array transducer. Its performance is limited by the configuration and size of the array transducer. In this paper, a method based on digital holographic interferometry is proposed to record the 3D ultrasonic wavefields instead of the array transducer, and the measurement system consisting of a pulsed laser, ultrasonic excitation, and synchronization and control circuit is designed. A consecutive sequence of holograms of ultrasonic wavefields are recorded by the system...
February 13, 2018: Sensors
Xiao-Sa Yang, Zhong-Wei Xu, Tai-Long Yi, Rui-Cheng Xu, Jie Li, Wen-Bin Zhang, Sai Zhang, Hong-Tao Sun, Ze-Qi Yu, Hao-Xiang Xu, Yue Tu, Shi-Xiang Cheng
Glioma is one of the most malignant forms of brain tumor, and has been of persistent concern due to its high recurrence and mortality rates, and limited therapeutic options. As a cardiac glycoside, ouabain has widespread applications in congestive heart diseases due to its positive cardiac inotropic effect by inhibiting Na+/K+‑ATPase. Previous studies have demonstrated that ouabain has antitumor activity in several types of human tumor, including glioma. However, the exact underlying mechanism remains to be elucidated...
February 12, 2018: Molecular Medicine Reports
Biagio Mandracchia, Oriella Gennari, Alessia Bramanti, Simonetta Grilli, Pietro Ferraro
The surface of a c-cut ferroelectric crystal at room temperature is characterized by the so-called screening surface charges, able to compensate the charge due to the spontaneous polarization. Recently, these charges inspired the investigation of the interaction affinity of live cells with lithium niobate and lithium tantalate crystals. However, different knowledge gaps still remain that prevent a reasonable application of these materials for biological applications. Here, a label-free holographic total internal reflection (HoloTIR) microscopy is shown; the technique is able to evaluate quantitatively the contact area of live fibroblast cells adhering onto the surface of a ferroelectric lithium niobate crystal...
February 6, 2018: Journal of Biophotonics
V Cazac, A Meshalkin, E Achimova, V Abashkin, V Katkovnik, I Shevkunov, D Claus, G Pedrini
Surface relief gratings and refractive index gratings are formed by direct holographic recording in amorphous chalcogenide nanomultilayer structures As2S3-Se and thin films As2S3. The evolution of the grating parameters, such as the modulation of refractive index and relief depth in dependence of the holographic exposure, is investigated. Off-axis digital holographic microscopy is applied for the measurement of the photoinduced phase gratings. For the high-accuracy reconstruction of the wavefront (amplitude and phase) transmitted by the fabricated gratings, we used a computational technique based on the sparse modeling of phase and amplitude...
January 20, 2018: Applied Optics
Runyu Cao, Wen Xiao, Xintong Wu, Lianwen Sun, Feng Pan
Cytoskeletons such as F-actin have different distributions in different cell parts and they are the cause of different degrees of cell collapse when the F-actin is disrupted. It is challenging to use conventional methods such as fluorescence microscopy and atomic force microscopy to conduct real-time and three-dimensional observations on the dynamic processes at different cell parts due to the slow measuring speed and the need for live-cell staining. In this study, the morphological variations of different bone cell parts caused by F-actin disruption are dynamically measured by using digital holographic microscopy (DHM)...
January 1, 2018: Biomedical Optics Express
Eszter Lajkó, Bernadett Tuka, Ferenc Fülöp, István Krizbai, József Toldi, Kálmán Magyar, László Vécsei, László Kőhidai
The neuroprotective actions of kynurenic acid (KYNA) and its derivatives in several neurodegenerative disorders [characterized by damage to the cerebral endothelium and to the blood-brain barrier (BBB)] are well established. Cell-extracellular matrix (ECM) adhesion is supposedly involved in recovery of impaired cerebral endothelium integrity (endothelial repair). The present work aimed to investigate the effects of KYNA and its synthetic derivatives on cellular behaviour (e.g. adhesion and locomotion) and on morphology of the GP8 rat brain endothelial cell line, modeling the BBB endothelium...
January 13, 2018: Journal of Neural Transmission
Balys Momgaudis, Stephane Guizard, Allan Bilde, Andrius Melninkaitis
In this Letter, a novel method to evaluate nonlinear refractive index using time-resolved digital holographic microscopy is introduced. To demonstrate the viability of the method, cross-correlative nonlinear refractive index values for sapphire are measured experimentally: 2.75·10-20  m2/W at 1030 nm and 4.10·10-20    m2/W 515 nm wavelengths. The obtained results for sapphire are compared to those available in literature obtained by other methods.
January 15, 2018: Optics Letters
José Ángel Picazo-Bueno, Dan Cojoc, Federico Iseppon, Vincent Torre, Vicente Micó
A single-shot water-immersion digital holographic microscope combined with broadband (white light) illumination mode is presented. This double imaging platform allows conventional incoherent visualization with phase holographic imaging of inspected samples. The holographic architecture is implemented at the image space (that is, after passing the microscope lens), thus reducing the sensitivity of the system to vibrations and/or thermal changes in comparison to regular interferometers. Because of the off-axis holographic recording principle, quantitative phase images of live biosamples can be recorded in a single camera snapshot at full-field geometry without any moving parts...
January 1, 2018: Applied Optics
Juan M Soto, José A Rodrigo, Tatiana Alieva
Quantitative label-free imaging is an important tool for the study of living microorganisms that, during the last decade, has attracted wide attention from the optical community. Optical diffraction tomography (ODT) is probably the most relevant technique for quantitative label-free 3D imaging applied in wide-field microscopy in the visible range. The ODT is usually performed using spatially coherent light illumination and specially designed holographic microscopes. Nevertheless, the ODT is also compatible with partially coherent illumination and can be realized in conventional wide-field microscopes by applying refocusing techniques, as it has been recently demonstrated...
January 1, 2018: Applied Optics
Marta Mikuła, Tomasz Kozacki, Michał Józwik, Julianna Kostencka
This paper proposes a measurement method of focusing objects with a high gradient shape of a small and large radius of curvature. The measurements are carried out on a Fourier digital holographic microscope with optimized illumination conditions maximizing the usage of the system's numerical aperture. The obtained fringe patterns are the result of interference of deformed spherical object and spherical reference waves. The key elements of the method are the aberration compensation and calibration procedures...
January 1, 2018: Applied Optics
Raul Castañeda, Jorge Garcia-Sucerquia
In this work, an off-axis digital holographic microscope operating in reflection mode and a telecentric regimen to produce 3D topography of a microscopy sample is shown. The main characteristics of the proposed method, which make it different from the previous works in the field, are the possibility of producing the 3D topography by a single shot over the complete field of view with sensitivity of λ/100, without phase perturbations introduced by the illuminating-imaging system, and with no further numerical processing beyond that required for recovering the phase map of the sample...
January 1, 2018: Applied Optics
Yumin Wu, Haobo Cheng, Yongfu Wen
To accurately measure ultrasmall rotation angles, a robust and effective method based on lensless digital holographic microscopy is proposed in this paper. The method combines holographic microscopy, solid geometry, and 3D measurement, including holographic measurement and angle measurement processes. We can calculate the 3D shape by the angular spectrum algorithm and the least-squares phase-unwrapping algorithm in the holographic process. According to the relationship between the surface shape and rotation angles, the real-time rotation angles can be calculated...
January 1, 2018: Applied Optics
D Marques, A Miranda, A G Silva, P R T Munro, P A A DE Beule
Some implementations of interference microscopy imaging use digital holographic measurements of complex scattered fields to reconstruct three-dimensional refractive index maps of weakly scattering, semi-transparent objects, frequently encountered in biological investigations. Reconstruction occurs through application of the object scattering potential which assumes an isotropic refractive index throughout the object. Here, we demonstrate that this assumption can in some circumstances be invalid for biological imaging due to the presence of lipid-induced optical anisotropy...
January 11, 2018: Journal of Microscopy
José A Rodrigo, Juan M Soto, Tatiana Alieva
The refractive index (RI) is an important optical characteristic that is often exploited in label-free microscopy for analysis of biological objects. A technique for 3D RI reconstruction of living cells has to be fast enough to capture the cell dynamics and preferably needs to be compatible with standard wide-field microscopes. To solve this challenging problem, we present a technique that provides fast measurement and processing of data required for real-time 3D visualization of the object RI. Specifically, the 3D RI is reconstructed from the measurement of bright-field intensity images, axially scanned by a high-speed focus tunable lens mounted in front of a sCMOS camera, by using a direct deconvolution approach designed for partially coherent light microscopy in the non-paraxial regime...
December 1, 2017: Biomedical Optics Express
Van K Lam, Thanh C Nguyen, Byung M Chung, George Nehmetallah, Christopher B Raub
The noninvasive, fast acquisition of quantitative phase maps using digital holographic microscopy (DHM) allows tracking of rapid cellular motility on transparent substrates. On two-dimensional surfaces in vitro, MDA-MB-231 cancer cells assume several morphologies related to the mode of migration and substrate stiffness, relevant to mechanisms of cancer invasiveness in vivo. The quantitative phase information from DHM may accurately classify adhesive cancer cell subpopulations with clinical relevance. To test this, cells from the invasive breast cancer MDA-MB-231 cell line were cultured on glass, tissue-culture treated polystyrene, and collagen hydrogels, and imaged with DHM followed by epifluorescence microscopy after staining F-actin and nuclei...
December 28, 2017: Cytometry. Part A: the Journal of the International Society for Analytical Cytology
Taesik Go, Hyeokjun Byeon, Sang Joon Lee
Cell types of erythrocytes should be identified because they are closely related to their functionality and viability. Conventional methods for classifying erythrocytes are time consuming and labor intensive. Therefore, an automatic and accurate erythrocyte classification system is indispensable in healthcare and biomedical fields. In this study, we proposed a new label-free sensor for automatic identification of erythrocyte cell types using a digital in-line holographic microscopy (DIHM) combined with machine learning algorithms...
December 15, 2017: Biosensors & Bioelectronics
Dingnan Deng, Weijuan Qu, Wenqi He, Yu Wu, Xiaoli Liu, Xiang Peng
We present a simple and effective compensation method for the off-axis tilt in common-path digital holographic microscopy (CPDHM) by introducing a rotating operation on the hologram. The proposed method mainly requires a digital reference hologram (DRH), which is a rotated version of the original one; it is assumed to be easy to obtain by rotating the specimen's hologram 180°. In this way, the off-axis tilt could be removed by subtracting the retrieved phase of DRH from the retrieved phase of the original hologram, but without any complex spectrum centering judgment, fitting procedures, or prior knowledge of the system...
December 15, 2017: Optics Letters
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