Bioengineering / Biyomühendislik
Permanent URI for this collectionhttps://hdl.handle.net/11147/4529
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Article Citation - WoS: 23Citation - Scopus: 30Magnetic Susceptibility-Based Protein Detection Using Magnetic Levitation(American Chemical Society, 2020) Yaman, Sena; Tekin, Hüseyin CumhurMagnetic levitation, which is a magnetic phenomenon of levitating particles suspended in a paramagnetic liquid under a nonuniform magnetic field, is a powerful tool for determining densities and magnetic properties of micro- and nanoparticles. The levitation height of particles in the magnetic field depends on the magnetic susceptibility and density difference between the object and the surrounding liquid. Here, we developed a magnetic susceptibility-based protein detection scheme in a low-cost and miniaturized magnetic levitation setup consisting of two opposing magnets to create a gradient of a magnetic field, a glass capillary channel to retain the sample, and two side mirrors to monitor inside the channel. The method includes the use of polymeric microspheres as mobile assay surfaces and magnetic nanoparticles as labels. The assay was realized by capturing the target protein to the polymer microspheres. Then, magnetic nanoparticles were attached onto the resulting microsphere-protein complex, creating a significant difference in the magnetic properties of polymer microspheres compared to those without protein. The change in the magnetic properties caused a change in the levitation height of the microspheres. The levitation heights and their distribution were then correlated to the amount of target proteins. The method enabled a detection limit of similar to 110 fg/mL biotinylated bovine serum albumin in serum. With the sandwich immunoassay developed for mouse immunoglobulin G, detection limits of 1.5 ng/mL and >10 ng/mL were achieved in buffer and serum, respectively. This approach sensed the minute changes in the volume magnetic susceptibility of the microspheres with a resolution of 4.2 x 10(-8) per 1 mu m levitation height change.Conference Object Citation - Scopus: 2Magnetic Levitation-Based Protein Detection Using Lensless Digital Inline Holographic Microscopy(The Chemical and Biological Microsystems Society (CBMS), 2019) Yaman, Sena; Delikoyun, Kerem; Tekin, Hüseyin CumhurWe present a portable protein detection platform based on magnetic levitation principle integrated with a lensless imaging system. In the platform, polymer microspheres are used to capture selectively target proteins and magnetic nanoparticle labels. The imaging system monitors the levitation height change of polymer microspheres with respect to the presence of target protein on their surfaces. This system enables the detection of target proteins down to ng/mL levels in a short time. © 2019 CBMS-0001.Article Citation - WoS: 79Citation - Scopus: 93Magnetic Force-Based Micro Fluidic Techniques for Cellular and Tissue Bioengineering(Frontiers Media S.A., 2018) Yaman, Sena; Anıl İnevi, Müge; Özçivici, Engin; Tekin, Hüseyin CumhurLive cell manipulation is an important biotechnological tool for cellular and tissue level bioengineering applications due to its capacity for guiding cells for separation, isolation, concentration, and patterning. Magnetic force-based cell manipulation methods offer several advantages, such as low adverse effects on cell viability and low interference with the cellular environment. Furthermore, magnetic-based operations can be readily combined with microfluidic principles by precisely allowing control over the spatiotemporal distribution of physical and chemical factors for cell manipulation. In this review, we present recent applications of magnetic force-based cell manipulation in cellular and tissue bioengineering with an emphasis on applications with microfluidic components. Following an introduction of the theoretical background of magnetic manipulation, components of magnetic force-based cell manipulation systems are described. Thereafter, different applications, including separation of certain cell fractions, enrichment of rare cells, and guidance of cells into specific macro- or micro-arrangements to mimic natural cell organization and function, are explained. Finally, we discuss the current challenges and limitations of magnetic cell manipulation technologies in microfluidic devices with an outlook on future developments in the field.Conference Object Citation - WoS: 7Citation - Scopus: 7Cell 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 CumhurSeparation 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: 2Density-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 CumhurMicroparticle/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.Conference Object Citation - WoS: 3Citation - Scopus: 4Biofabrication of Cellular Structures Using Weightlessness as a Biotechnological Tool(IEEE, 2019) Anıl İnevi, Müge; Sarıgil, Öykü; Yaman, Sena; Yalçın Özuysal, Özden; Meşe, Gülistan; Tekin, Hüseyin Cumhur; Özçivici, EnginGravity is an important biomechanical signal effecting the morphology and function of organisms. Reduction of gravitational forces, as experienced during spaceflight, cause alterations in the biological systems. Magnetic levitation technique is one of the most recent ground-based technology to mimic weightlessness environment. In addition to providing a platform to investigate biological effects of the weightlessness, this platform presents a novel opportunity to biofabricate 3-dimensional (3D) structures in a scaffold-and nozzle-free fashion. In this study, various controllable self-assembled 3D living structures were fabricated via magnetic levitation technique. This strategy may offer an easy and cost-effective opportunity for a wide range of space biotechnology researches.