Bioengineering / Biyomühendislik
Permanent URI for this collectionhttps://hdl.handle.net/11147/4529
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Review Citation - WoS: 30Citation - Scopus: 33Molecular Separation by Using Active and Passive Microfluidic Chip Designs: a Comprehensive Review(Wiley, 2023) Ebrahimi, Aliakbar; Didarian, Reza; Shih, Chih-Hsin; Nasseri, Behzad; Ethan Li, Yi-Chen; Shih, Steven; İçöz, Kutay; Tarım, Ergün Alperay; Akpek, Ali; Çeçen, Berivan; Bal Öztürk, Ayça; Güleç, Kadri; Tarım, Burcu Sırma; Tekin, Hüseyin CumhurSeparation and identification of molecules and biomolecules such as nucleic acids, proteins, and polysaccharides from complex fluids are known to be important due to unmet needs in various applications. Generally, many different separation techniques, including chromatography, electrophoresis, and magnetophoresis, have been developed to identify the target molecules precisely. However, these techniques are expensive and time consuming. “Lab-on-a-chip” systems with low cost per device, quick analysis capabilities, and minimal sample consumption seem to be ideal candidates for separating particles, cells, blood samples, and molecules. From this perspective, different microfluidic-based techniques have been extensively developed in the past two decades to separate samples with different origins. In this review, “lab-on-a-chip” methods by passive, active, and hybrid approaches for the separation of biomolecules developed in the past decade are comprehensively discussed. Due to the wide variety in the field, it will be impossible to cover every facet of the subject. Therefore, this review paper covers passive and active methods generally used for biomolecule separation. Then, an investigation of the combined sophisticated methods is highlighted. The spotlight also will be shined on the elegance of separation successes in recent years, and the remainder of the article explores how these permit the development of novel techniques. © 2023 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.Review Citation - WoS: 23Citation - Scopus: 24Microfluidic-Based Technologies for Diagnosis, Prevention, and Treatment of Covid-19: Recent Advances and Future Directions(Springer, 2023) Tarım, Ergün Alperay; Anıl İnevi, Müge; Özkan, İlayda; Keçili, Seren; Bilgi, Eyüp; Başlar, Muhammet Semih; Özçivici, Engin; Öksel Karakuş, Ceyda; Tekin, Hüseyin CumhurThe COVID-19 pandemic has posed significant challenges to existing healthcare systems around the world. The urgent need for the development of diagnostic and therapeutic strategies for COVID-19 has boomed the demand for new technologies that can improve current healthcare approaches, moving towards more advanced, digitalized, personalized, and patient-oriented systems. Microfluidic-based technologies involve the miniaturization of large-scale devices and laboratory-based procedures, enabling complex chemical and biological operations that are conventionally performed at the macro-scale to be carried out on the microscale or less. The advantages microfluidic systems offer such as rapid, low-cost, accurate, and on-site solutions make these tools extremely useful and effective in the fight against COVID-19. In particular, microfluidic-assisted systems are of great interest in different COVID-19-related domains, varying from direct and indirect detection of COVID-19 infections to drug and vaccine discovery and their targeted delivery. Here, we review recent advances in the use of microfluidic platforms to diagnose, treat or prevent COVID-19. We start by summarizing recent microfluidic-based diagnostic solutions applicable to COVID-19. We then highlight the key roles microfluidics play in developing COVID-19 vaccines and testing how vaccine candidates perform, with a focus on RNA-delivery technologies and nano-carriers. Next, microfluidic-based efforts devoted to assessing the efficacy of potential COVID-19 drugs, either repurposed or new, and their targeted delivery to infected sites are summarized. We conclude by providing future perspectives and research directions that are critical to effectively prevent or respond to future pandemics.Article Citation - WoS: 15Citation - Scopus: 16Electromechanical Rt-Lamp Device for Portable Sars-Cov Detection(Elsevier, 2023) Tarım, Ergün Alperay; Öksüz, Cemre; Karakuzu, Betül; Appak, Özgür; Sayıner, Ayça Arzu; Tekin, Hüseyin CumhurRapid point-of-care tests for infectious diseases are essential, especially in pandemic conditions. We have developed a point-of-care electromechanical device to detect SARS-CoV-2 viral RNA using the reverse-transcription loop-mediated isothermal amplification (RT-LAMP) principle. The developed device can detect SARS-CoV-2 viral RNA down to 103 copies/mL and from a low amount of sample volumes (2 μL) in less than an hour of standalone operation without the need for professional labor and equipment. Integrated Peltier elements in the device keep the sample at a constant temperature, and an integrated camera allows automated monitoring of LAMP reaction in a stirring sample by using colorimetric analysis of unfocused sample images in the hue/saturation/value color space. This palm-fitting, portable and low-cost device does not require a fully focused sample image for analysis, and the operation could be stopped automatically through image analysis when the positive test results are obtained. Hence, viral infections can be detected with the portable device produced without the need for long, expensive, and labor-intensive tests and equipment, which can make the viral tests disseminated at the point-of-care.Conference Object Size-Based Microparticle Seperation Using Negative Magnetophoresis(Chemical and Biological Microsystems Society, 2021) Solmaz Özçelik, Özge; Öksüz, Cemre; Tekin, Hüseyin CumhurWe present a new size-based microparticle separation device using negative magnetophoresis. Microparticles spiked in the paramagnetic medium were filtered with respect to their sizes in a microfluidic channel placed between two magnets. Negative magnetophoresis allows large microparticles to be captured before the magnets, while small microparticles pass through the magnets under a constant flow. With this method, we reached 84.2% capturing efficiency of large microparticles (44 µm diameter) and capturing purity of 80.3% in the presence of small microparticles (17 µm diameter) at 3 µL/min flow rate. The capturing purity could further improve up to 99% by increasing the flow rate.Article Citation - WoS: 10Citation - Scopus: 14An Electromechanical Lab-On Platform for Colorimetric Detection of Serum Creatinine(American Chemical Society, 2022) Karakuzu, Betül; Tarım, Ergün Alperay; Öksüz, Cemre; Tekin, Hüseyin CumhurChronic kidney disease (CKD) is a high-cost disease that affects approximately one in ten people globally, progresses rapidly, results in kidney failure or dialysis, and triggers other diseases. Although clinically used serum creatinine tests are used to evaluate kidney functions, these tests are not suitable for frequent and regular control at-home settings that obstruct the regular monitoring of kidney functions, improving CKD management with early intervention. This study introduced a new electromechanical lab-on-a-chip platform for point-of-care detection of serum creatinine levels using colorimetric enzyme-linked immunosorbent assay (ELISA). The platform was composed of a chip containing microreservoirs, a stirring bar coated with creatinine-specific antibodies, and a phone to detect color generated via ELISA protocols to evaluate creatinine levels. An electromechanical system was used to move the stirring bar to different microreservoirs and stir it inside them to capture and detect serum creatinine in the sample. The presented platform allowed automated analysis of creatinine in ~50 min down to ~1 and ~2 mg/dL in phosphate-buffered saline (PBS) and fetal bovine serum (FBS), respectively. Phone camera measurements in hue, saturation, value (HSV) space showed sensitive analysis compared to a benchtop spectrophotometer that could allow low-cost analysis at point-of-care.Conference Object Citation - WoS: 1Citation - Scopus: 2A Vacuum-Integrated Centrifugal Microfluidic Chip for Density-Based Separation of Microparticles(IEEE, 2021) Öksüz, Cemre; Tekin, Hüseyin CumhurHere we present a new vacuum-integrated centrifugal microfluidic chip for the density-based separation of microparticles. A sample was loaded in a fluidic channel using the gas permeability feature of polydimethylsiloxane (PDMS) membrane between fluidic and control channels. Vacutun was applied from control channel to drive a density media and then the sample containing microparticles in the dead-end fluidic channel. Afterwards, the chip was disconnected from the vacuum and it was centrifugated. If the sample contains microparticles denser than the density media, the microparticles are sedimented at the end of the microfluidic channel so that these particles can be separated from remaining the lower density particles. With this approach, we separated 1.09 g/mL microparticles with 82,6% efficiency and 99% purity from 1.02 g/mL microparticles. Separated particles in the microfluidic chip can also be inspected under a microscope for further analysis. This simple approach offers high efficient density-based separation of microparticles with close densities.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.Article Kronik Hastaların Uzaktan İzlemine Yönelik Teletıp Platformu(Dokuz Eylül Üniversitesi, 2020) Tekin, Hüseyin CumhurKronik hasta sayısı dünya genelinde artış göstermektedir. Bu nedenle kronik hastalıkların kontrol altına alınabilmelerinde etkili bir hastalık yönetimi ihtiyacı doğmuştur. Bu hastalıkların kontrolünde hastaların uzaktan takibine olanak sağlayan teletıp sistemlerinin büyük fayda sağlama potansiyelleri vardır. Etkin teletıp sistemlerinin geliştirilmesinde ise söz konusu bu sistemlerin ölçeklenebilirliğini ve sürdürebilirliğini sağlamak önem arz etmektedir. Bu çalışmada, kronik hastaların uzaktan izlemini gerçekleştirebilmek için yeni bir teletıp platformu önerilmektedir. Bu platform hastalara, sağlık verilerini sistem üstünden takiplerini yapan sağlık personeli ile doğrudan ve kolaylıkla paylaşabilme olanağı sunmaktadır. Sağlık personeli ise, hastalık seyrindeki gelişmeleri ve tedavi hedeflerini bu veriler sayesinde uzaktan kontrol edebilmektedir. Ayrıca sağlık personeli, platform üstünden hastaya özel olarak belirleyeceği sağlık verisi eşik değerleri ile, kendisine ve/veya hastaya otomatik bildirim mesajı gönderebilmekte, böylelikle hasta verilerini sürekli manuel olarak incelemek yerine, platform üstünden gelecek bildirimler vasıtasıyla hastaya gerekli müdahaleyi vakit kaybetmeksizin yapabilmektedir. Önerilen platform ile kronik hastalık yönetimi iyileştirilebileceği gibi, sağlık personeline olabildiğince az iş yükü getirilerek verilecek sağlık hizmetinde verim ve kalite artışı sağlanabilecek, böylelikle platformun sürdürülebilirliği de temin edilebilecektir. Çalışmada platformun ölçeklenebilirliği, eş zamanlı istek testleri ile analiz edilmiştir. Platform üstünden bildirim mesajı göndermenin, 500 eş zamanlı istek için düşük tepki süresi (<750 ms), yüksek verimlilik (>200 istek/s) ve düşük hata oranı (<%1.5) ile gerçekleştiği gözlenmiştir. Bu sonuçlar tasarlanan teletıp platformunun, birçok kullanıcıdan gelen veri akışının üstesinden gelebileceğini ve platformun ölçeklenebilir olduğunu göstermektedir.Conference Object Deep Convolutional Neural Networks for Viability Analysis Directly From Cell Holograms Captured Using Lensless Holographic Microscopy(The Chemical and Biological Microsystems Society (CBMS), 2019) Delikoyun, Kerem; Çine, Ersin; Anıl İnevi, Müge; Özçivici, Engin; Özuysal, Mustafa; Tekin, Hüseyin CumhurCell viability analysis is one of the most widely used protocols in the fields of biomedical sciences. Traditional methods are prone to human error and require high-cost and bulky instrumentations. Lensless digital inline holographic microscopy (LDIHM) offers low-cost and high resolution imaging. However, recorded holograms should be digitally reconstructed to obtain real images, which requires intense computational work. We introduce a deep transfer learning-based cell viability classification method that directly processes the hologram without reconstruction. This new model is only trained once and viability of each cell can be predicted from its hologram. © 2019 CBMS-0001.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.
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