Bioengineering / Biyomühendislik

Permanent URI for this collectionhttps://hdl.handle.net/11147/4529

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Author: search.filters.author.Delikoyun, KeremCOAR Access Rights: search.filters.coarAccessRights.open access

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Now showing 1 - 5 of 5
  • Conference Object
    Citation - WoS: 2
    Citation - Scopus: 2
    Portatif ve Düşük Maliyetli Merceksiz Holografik Mikroskop Platformu ile Nanoparçacık Tespiti
    (IEEE, 2020) Delikoyun, Kerem; Keçili, Seren; Tekin, Hüseyin Cumhur
    In the biological and medical science, detection of biomolecule at very low concentration (<100 pg/mL) is of great importance and it is extensively used in the diagnosis of diseases, drug response monitoring and cancer research. For biomolecule detection tests, captured biomolecules generate signals (fluorescence, color, etc.), which are analyzed by trained personnel in bulky, high cost and fragile devices. However, for clinical applications, the access to these tests is very difficult at resource-limited settings. Lensless holographic microscopy provides high resolution imaging of samples without the need of expensive and fragile optical elements (mirror, lens, filter, etc.) used in traditional imaging technologies. While this technology offers a robust, portable and low-cost design, it enables fully automated processing of the sample image with digital processing schemes and this can also help eliminate user error. In this study, lensless holographic microscopy platform, which can be used in surface coverage assays for the detection of biomolecules, is proposed. It has been shown that nanoparticles (700-1200 nm) used as labels in surface coverage assays for the detection of biomolecules could be sensed on the platform. Therefore, it is anticipated that biomolecules detection could be realized rapidly and sensitively with this easy-to-use and low-cost imaging platform at the location where the high-level health institutions are not available and even at point-of-care settings.
  • Article
    Citation - WoS: 24
    Citation - Scopus: 30
    Hologlev: a Hybrid Magnetic Levitation Platform Integrated With Lensless Holographic Microscopy for Density-Based Cell Analysis
    (American Chemical Society, 2021) Delikoyun, Kerem; Yaman, Sena; Yılmaz, Esra; Sarıgil, Öykü; Anıl İnevi, Müge; Telli, Kübra; Yalçın Özuysal, Özden
    In clinical practice, a variety of diagnostic applications require the identification of target cells. Density has been used as a physical marker to distinguish cell populations since metabolic activities could alter the cell densities. Magnetic levitation offers great promise for separating cells at the single cell level within heterogeneous populations with respect to cell densities. Traditional magnetic levitation platforms need bulky and precise optical microscopes to visualize levitated cells. Moreover, the evaluation process of cell densities is cumbersome, which also requires trained personnel for operation. In this work, we introduce a device (HologLev) as a fusion of the magnetic levitation principle and lensless digital inline holographic microscopy (LDIHM). LDIHM provides ease of use by getting rid of bulky and expensive optics. By placing an imaging sensor just beneath the microcapillary channel without any lenses, recorded holograms are processed for determining cell densities through a fully automated digital image processing scheme. The device costs less than $100 and has a compact design that can fit into a pocket. We perform viability tests on the device by levitating three different cell lines (MDA-MB-231, U937, D1 ORL UVA) and comparing them against their dead correspondents. We also tested the differentiation of mouse osteoblastic (7F2) cells by monitoring characteristic variations in their density. Last, the response of MDA-MB-231 cancer cells to a chemotherapy drug was demonstrated in our platform. HologLev provides cost-effective, label-free, fully automated cell analysis in a compact design that could be highly desirable for laboratory and point-of-care testing applications.
  • Conference Object
    Citation - WoS: 5
    Citation - Scopus: 8
    Lensless Digital In-Line Holographic Microscopy for Space Biotechnology Applications
    (Institute of Electrical and Electronics Engineers Inc., 2019) Delikoyun, Kerem; Çine, Ersin; Anıl İnevi, Müge; Özuysal, Mustafa; Özçivici, Engin; Tekin, Hüseyin Cumhur
    Biomechanical changes at cellular level can dramatically affect living organisms in both aviation and space applications. Weightlessness induces morphological alteration of cells, which leads to tissue loss. Therefore, scientists have been studying the effect of weightlessness using cell culture based biological experiments using conventional microscopes. However, strict requirements regarding cost, weight and functionality limit the use of conventional microscopes in space environment. Lensless digital in-line holographic microscopy enables to use low-weight, low-cost and robust elements, such as a light emitting diode (LED), an aperture and an imaging sensor, instead of bulky, expensive and fragile optical elements, such as lenses, mirrors and filters. This technology offers a high field of view compared to conventional microscopes without affecting the resolution and it is also suitable for remote sensing applications with automated imaging capabilities. Here, we present a portable digital in-line holographic microscopy platform that allows to visualize cells and to analyze their viability in a microfluidic chip. The platform offers microscopic imaging with 1.55 mu m spatial resolution, 21.7 mm(2) field of view and image coloring capability. This platform could potentially play an important role in space biotechnology applications by enabling low-cost, high-resolution and portable monitoring of cells.
  • Conference Object
    Citation - WoS: 7
    Citation - Scopus: 7
    Cell Separation With Hybrid Magnetic Levitation-Based Lensless Holographic Microscopy Platform
    (Institute of Electrical and Electronics Engineers Inc., 2019) Delikoyun, Kerem; Yaman, Sena; Anıl İnevi, Müge; Özçivici, Engin; Tekin, Hüseyin Cumhur
    Separation of target cells in a heterogeneous solution is of great importance for clinical studies especially for immunology and oncology. Separated cells can be used for diagnostic applications ranging from whole blood counting to isolation of circulating tumor cells (CTC) for personalized medicine. Recent separation technologies rely on labelling and identifying target cells with variety of labelling principle such as fluorescence or magnetic tags. However, they require labor-intensive processes, long analysis time, and expensive chemical reagents and instrumentation. Hence, their usage is limited to well-equipped centralized laboratories. There is a need for a rapid, sensitive, low-cost and automated cell separation technology to disseminate usage of this technology even in rural areas. Magnetic levitation is a powerful cell separation method, which distinguishes cells based on their levitation heights depending on cell density. However, magnetic levitation-based separation technologies require traditional, bulky and expensive microscopes for analysis. Lensless digital inline holographic microscopy (LDIHM) systems are composed of a simple illumination system containing an LED, a pinhole, and an imaging sensor for high-resolution microscopic imaging, which eliminates needs of highly fragile and expensive optics as in traditional microscopy. Here, we introduced a novel hybrid and portable cell separation platform, where magnetic levitation technology is integrated with LDIHM system for automated analysis of cell levitation heights. Using this platform, three different cell lines are successfully separated. Live and dead cells having distinguished levitation heights can be also identified in the platform.
  • Conference Object
    Citation - Scopus: 2
    Density-Based Separation of Microparticles Using Magnetic Levitation Technology Integrated on Lensless Holographic Microscopy Platform
    (Institute of Electrical and Electronics Engineers Inc., 2019) Delikoyun, Kerem; Yaman, Sena; Tekin, Hüseyin Cumhur
    Microparticle/cell separation is one of the most important applications in the field of biomedical sciences particularly for cell sorting and protein assays. There are variety of different separation technologies introduced in the literature that the main limitations are large amount of sample, expensive chemical use besides of requirement of a labeling procedure (i.e. fluorescent/magnetic labeling), complex machinery, and high operational costs. Magnetic levitation-based separation offers simple, rapid and precise separation of microparticles based on their densities by suspending them in a glass microcapillary between two opposing magnets. Traditionally, magnetic levitation-based microparticle separation and identification procedure is performed by imaging under bulky microscopes composed of fragile and expensive optics and require trained personnel to operate which makes the whole procedure costly, time consuming and prone to human error. Lensless digital inline holographic microscope (LDIHM) eliminates the need for sophisticated optics by replacing simple illumination and recording scheme that can be reduced into few widely-Available and cost-effective components. Thus, inspection procedure is mostly carried out on digitally processing captured holograms so that dependency on optical components and human error is dramatically reduced alongside using cost-effective and handheld device. Here, we introduce a novel hybrid platform that brings the advantages of magnetic levitation system with lensless digital inline holographic microscope for precise separation and identification of microparticles based on their densities. In the platform, it was shown that 1.026 g/mL and 1.090 g/mL microparticles were successfully identified. © 2019 IEEE.