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Holographic microscopy

Birgit Janicke, Andreas Kårsnäs, Peter Egelberg, Kersti Alm
Cell proliferation assays are widely applied in biological sciences to understand the effect of drugs over time. However, current methods often assess cell population growth indirectly, that is, the cells are not actually counted. Instead other parameters, for example, the amount of protein, are determined. These methods often also demand phototoxic labels, have low temporal resolution, or employ end-point assays, and frequently are labor intensive. We have developed a robust and label-free kinetic cell proliferation assay with high temporal resolution for adherent cells using digital holographic microscopy (DHM), one of many quantitative phase microscopy techniques...
April 24, 2017: Cytometry. Part A: the Journal of the International Society for Analytical Cytology
Jiwei Zhang, Siqing Dai, Chaojie Ma, Jianglei Di, Jianlin Zhao
We develop a common-path digital holographic microscopy based on prism-coupling surface plasmon resonance (SPR) for near-field phase imaging. A single beam splitter with specific configuration is introduced in an SPR imaging system to realize off-axis holographic recording. By measuring the phase shift difference of the reflected light at SPR exploiting the proposed holographic microscopy with high temporal stability, near-field characteristic measurement can be realized. With its simplicity, vibration isolation, and inherent capability of phase curvature compensation, the recommended system shows advanced performance in monitoring tiny refractive index variations and imaging biological tissues...
April 10, 2017: Applied Optics
Byung-Mok Kim, Seong-Jin Park, Eun-Soo Kim
Single-shot digital holographic microscopy (SS-DHM) with a modified lateral-shearing interferometer (MLSI) based on computational telecentricity is proposed. The proposed system is composed of three-step processes such as optical recording, digital compensation and numerical reconstruction processes. In the 1st step, the object beam is optically recorded with the MLSI, where a tube lens is set to be located at the slightly shorter distance than its focal length from the objective lens. Then, another phase factor due to the deviated locating of the tube lens from its focal length is additionally generated, which is called an additional quadratic phase factor (AQPF)...
March 20, 2017: Optics Express
Jian-Hai Yu, Xu-Ling Liu, Yu-Jing Liu, Xiao-En He, Yuan Hui, Bao Zhang, Li Zhu, Wei Zhao
OBJECTIVE: To monitor the 3-dimensional (3D) morphological changes of C6/36 cells during dengue virus (DENV) infection using a live-cell imaging technique based on digital holographic microscopy and provide clues for better understanding the mechanisms of DENV infection. METHODS: C6/36 cells were seeded in 6-well plates to determine the optimal imaging density under a holographic cell imager, and the morphological changes of the cells were recorded in response to a culture temperature change from 28 degrees celsius; to 37 degrees celsius; C6/36 cells were infected with 4 DENV strains with different serotypes at 28 degrees celsius; and incubated at 37 degrees celsius; for 24 h, and the 3D holograms and relevant morphological parameters were recorded at different time points using HoloMonitor M4 holographic cell imaging and analysis system...
March 20, 2017: Nan Fang Yi Ke da Xue Xue Bao, Journal of Southern Medical University
Mostafa Aakhte, Vahid Abbasian, Ehsan Ahadi Akhlaghi, Ali-Reza Moradi, Arun Anand, Bahram Javidi
In this paper, we use a glass microsphere incorporated into a digital holographic microscope to increase the effective resolution of the system, aiming at precise cell identification. A Mirau interferometric objective is employed in the experiments, which can be used for a common-path digital holographic microscopy (DHMicroscopy) arrangement. High-magnification Mirau objectives are expensive and suffer from low working distances, yet the commonly used low-magnification Mirau objectives do not have high lateral resolutions...
March 20, 2017: Applied Optics
Siddharth Rawat, Satoru Komatsu, Adam Markman, Arun Anand, Bahram Javidi
We propose a low-cost, compact, and field-portable 3D printed holographic microscope for automated cell identification based on a common path shearing interferometer setup. Once a hologram is captured from the portable setup, a 3D reconstructed height profile of the cell is created. We extract several morphological cell features from the reconstructed 3D height profiles, including mean physical cell thickness, coefficient of variation, optical volume (OV) of the cell, projected area of the cell (PA), ratio of PA to OV, cell thickness kurtosis, cell thickness skewness, and the dry mass of the cell for identification using the random forest (RF) classifier...
March 20, 2017: Applied Optics
Teli Xi, Jianglei Di, Xiaofeng Guan, Ying Li, Chaojie Ma, Jiwei Zhang, Jianlin Zhao
Phase-shifting infrared digital holographic microscopy based on a homemade all-fiber variable phase shifter is presented to quantitatively obtain the phase distribution of an object wave carrying the information of a transparent specimen in the infrared band. The all-fiber variable phase shifter, which consists of a tubular piezoelectric transducer (PZT) and a single-mode fiber, can accurately produce any phase shift between 0 and 2π by modulating the driving voltage of the tubular PZT. Taking measurements of different staircase structures on a silicon wafer as samples, two configurations are presented based on different phase-shifting implementations: one is a slight off-axis two-step phase shift and the other is an in-line four-step phase shift...
April 1, 2017: Applied Optics
Yu-Chih Lin, Hui-Chi Chen, Han-Yen Tu, Chin-Yu Liu, Chau-Jern Cheng
This study presents a novel tomographic imaging technique for living biomedical samples using an optically driven full-angle rotation scheme based on digital holographic microscopy, in which the three-dimensional refractive index distribution inside the sample can be measured and analyzed. To accomplish the full-angle sample rotation, two optical traps are driven by highly focused spots on the top and bottom of the sample. The rim image of the sample outside the focal depth at the different rotation angles and propagation distances can be corrected and compensated, respectively, via numerical focusing; therefore, tomographic imaging of the sample can be conducted...
April 1, 2017: Optics Letters
Meng Qi, Xiangjun Gong, Bo Wu, Guangzhao Zhang
Landing of bacteria for adhesion on a surface is a common phenomenon in our life. However, how surface properties are involved in this process remains largely unclear. Using digital holographic microscopy, we investigated the three-dimensional motions of flagellate Escherichia coli swimming near polymeric surfaces with different properties in aqueous solution before adhesion. We monitored the bacteria landing dynamics, which shows that the density distribution, the probability, and the orientation for collisions of the bacteria are determined by their motility but are slightly affected by the surface properties...
March 28, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Dhananjay Kumar Singh, Caroline C Ahrens, Wei Li, Siva A Vanapalli
Large-scale and label-free phenotyping of cells holds great promise in medicine, especially in cancer diagnostics and prognosis. Here, we introduce inline digital holography microscopy for volumetric imaging of cells in bulk flow and fingerprinting of flowing tumor cells based on two metrics, in-focus scattered intensity and cell diameter. Using planar distribution of immobilized particles, we identify the optimal recording distance and microscope objective magnification that minimizes the error in measurement of particle position, size and scattered intensity...
February 1, 2017: Biomedical Optics Express
Lena Kastl, Michael Isbach, Dieter Dirksen, Jürgen Schnekenburger, Björn Kemper
The potential of quantitative phase imaging (QPI) with digital holographic microscopy (DHM) for quantification of cell culture quality was explored. Label-free QPI of detached single cells in suspension was performed by Michelson interferometer-based self-interference DHM. Two pancreatic tumor cell lines were chosen as cellular model and analyzed for refractive index, volume, and dry mass under varying culture conditions. Firstly, adequate cell numbers for reliable statistics were identified. Then, to characterize the performance and reproducibility of the method, we compared results from independently repeated measurements and quantified the cellular response to osmolality changes of the cell culture medium...
March 6, 2017: Cytometry. Part A: the Journal of the International Society for Analytical Cytology
Naomi McReynolds, Fiona G M Cooke, Mingzhou Chen, Simon J Powis, Kishan Dholakia
The ability to identify and characterise individual cells of the immune system under label-free conditions would be a significant advantage in biomedical and clinical studies where untouched and unmodified cells are required. We present a multi-modal system capable of simultaneously acquiring both single point Raman spectra and digital holographic images of single cells. We use this combined approach to identify and discriminate between immune cell populations CD4+ T cells, B cells and monocytes. We investigate several approaches to interpret the phase images including signal intensity histograms and texture analysis...
March 3, 2017: Scientific Reports
José Ángel Picazo-Bueno, Zeev Zalevsky, Javier García, Vicente Micó
Superresolution capability by angular and time multiplexing is implemented onto a regular microscope. The technique, named superresolved spatially multiplexed interferometric microscopy (S2MIM), follows our previously reported SMIM technique [Opt. Express22, 14929 (2014)OPEXFF1094-408710.1364/OE.22.014929, J. Biomed. Opt.21, 106007 (2016)JBOPFO1083-366810.1117/1.JBO.21.10.106007] improved with superresolved imaging. All together, S2MIM updates a commercially available non-holographic microscope into a superresolved holographic one...
March 1, 2017: Optics Letters
C Allier, S Morel, R Vincent, L Ghenim, F Navarro, M Menneteau, T Bordy, L Hervé, O Cioni, X Gidrol, Y Usson, J-M Dinten
They present results for lens-free microscopy for the imaging of dense cell culture. With this aim, they use a multiwavelength LED illumination with well separated wavelengths, together with the implementation of an appropriate holographic reconstruction algorithm. This allows for a fast and efficient reconstruction of the phase image of densely packed cells (up to 700 cells/mm(2) ) over a large field of view of 29.4 mm(2) . Combined with the compactness of the system which fits altogether inside an incubator, lens-free microscopy becomes a unique tool to monitor cell cultures over several days...
February 27, 2017: Cytometry. Part A: the Journal of the International Society for Analytical Cytology
Heng-Jui Liu, Chih-Kuo Wang, Dong Su, Tahta Amrillah, Ying-Hui Hsieh, Kun-Hong Wu, Yi-Chun Chen, Jenh-Yih Juang, Lukas M Eng, Shien-Uang Jen, Ying-Hao Chu
A bimorph composed of ferrimagnetic cobalt ferrite (CoFe2O4, CFO) and flexible muscovite was fabricated via van der Waals epitaxy. The combination of X-ray diffraction and transmission electron microscopy was conducted to reveal the heteroepitaxy of the CFO/muscovite system. The robust magnetic behaviors against mechanical bending were characterized by hysteresis measurements and magnetic force microscopy, which maintain a saturation magnetization (Ms) of ∼120-150 emu/cm(3) under different bending states...
March 1, 2017: ACS Applied Materials & Interfaces
Taesik Go, Hyeokjun Byeon, Sang Joon Lee
Viscoelastic fluid flow-induced cross-streamline migration has recently received considerable attention because this process provides simple focusing and alignment over a wide range of flow rates. The lateral migration of particles depends on the channel geometry and physicochemical properties of particles. In this study, digital in-line holographic microscopy (DIHM) is employed to investigate the lateral migration of human erythrocytes induced by viscoelastic fluid flow in a rectangular microchannel. DIHM provides 3D spatial distributions of particles and information on particle orientation in the microchannel...
January 24, 2017: Scientific Reports
Nowroji Kavitha, Yeng Chen, Jagat R Kanwar, Sreenivasan Sasidharan
Phaleria macrocarpa (Boerl.) is a well-known medicinal plant and have been extensively used as traditional medicine for ages in treatment of various diseases. The purpose of this study was to determine the in situ cytotoxicity effect P. macrocarpa fruit ethyl acetate fraction (PMEAF) by using various conventional and modern microscopy techniques. The cytotoxicity of PMEAF treated MDA-MB-231 cells was determined through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay and CyQuant Cell Proliferation Assay after 24h of treatment...
March 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
Tobias Meinert, Benjamin Alexander Gutwein, Alexander Rohrbach
Light-sheet microscopy enables fast 3D, high-contrast imaging in biology and colloidal sciences. Recently, the controlled transport of living embryos or small colloids through stable glass capillaries is manifold interesting. Although they hardly impair the sample, glass capillaries spoil the image by generating significant aberrations of the illumination and detection light. Here, we analyze the deflection of illuminating Bessel beams at the capillary by k-spectral shifting, and correct for it by a beam deflector...
January 15, 2017: Optics Letters
Po-Hao Wang, Vijay Raj Singh, Jau-Min Wong, Kung-Bin Sung, Yuan Luo
Confocal imaging techniques offer an optical sectioning capability to acquire three-dimensional information from various volumetric samples by discriminating the desired in-focus signals from the out-of-focus background. However, confocal, in general, requires a point-by-point scan in both the lateral and axial directions to reconstruct three-dimensional images. In addition, axial scanning in confocal is slower than scanning in lateral directions. In this Letter, a non-axial-scanning multifocal confocal microscope incorporating multiplexed holographic gratings in illumination and dual detection for depth discrimination is presented...
January 15, 2017: Optics Letters
Junwei Min, Baoli Yao, Steffi Ketelhut, Christian Engwer, Burkhard Greve, Björn Kemper
We present a simple and fast phase aberration compensation method in digital holographic microscopy (DHM) for quantitative phase imaging of living cells. By analyzing the frequency spectrum of an off-axis hologram, phase aberrations can be compensated for automatically without fitting or pre-knowledge of the setup and/or the object. Simple and effective computation makes the method suitable for quantitative online monitoring with highly variable DHM systems. Results from automated quantitative phase imaging of living NIH-3T3 mouse fibroblasts demonstrate the effectiveness and the feasibility of the method...
January 15, 2017: Optics Letters
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