Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Book Part Sample Preparation Using Microfluidic Technologies for Non-Invasive Tests(Elsevier, 2025) Oksuz, C.; Tarim, E.A.; Ozcan, H.A.; Koc, S.; Tekin, H.C.The collection of a biological sample and the steps carried out to obtain the target in a sample covers the sample preparation procedures which are one of the important steps for diagnostic tests. Removing interferences in a complex sample, preventing undesirable reactions, separating, purifying, and enriching the sample are among the steps that can be applied to samples for analysis. Non-invasive tests include samples such as urine, saliva, sweat, tear, breath and are preferred because they are simple, painless, cost-effective and cause fewer complications. In traditional methods applied in clinics, most of the steps such as centrifugation, pipetting, staining, and washing are performed manually by a technician. For this reason, tests are costly, require long analysis time, and have a significant risk of contamination and manual errors. Microfluidic technologies allow automating sample collection and preparation steps by integrating many components on a single chip. Thereby, low-volume samples can be processed automatically with high efficiency and purity. In this chapter, the sample preparation methods used in microfluidic devices for non-invasive tests analyzing human samples including sweat, urine, saliva, tears, sexual samples, and other body fluids are reviewed. This information aims to facilitate the development of potential sample preparation methods and applications for non-invasive diagnostic tests. © 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Review Citation - WoS: 1Citation - Scopus: 2Organ-On Platforms for Drug Development, Cellular Toxicity Assessment, and Disease Modeling(Tubitak Scientific & Technological Research Council Turkey, 2024) Khurram, Muhammad Maaz; Cinel, Gokturk; Yesil Celiktas, Ozlem; Bedir, ErdalOrgans-on-chips (OoCs) or microphysiological platforms are biomimetic systems engineered to emulate organ structures on microfluidic devices for biomedical research. These microdevices can mimic biological environments that enable cell-cell interactions on a small scale by mimicking 3D in vivo microenvironments outside the body. Thus far, numerous single and multiple OoCs that mimic organs have been developed, and they have emerged as forerunners for drug efficacy and cytotoxicity testing. This review explores OoC platforms to highlight their versatility in studies of drug safety, efficacy, and toxicity. We also reflect on the potential of OoCs to effectively portray disease models for possible novel therapeutics, which is difficult to achieve with traditional 2D in vitro models, providing an essential basis for biologically relevant research.Article Citation - WoS: 6Citation - Scopus: 7Engineering Free-Standing Electrospun Pllcl Fibers on Microfluidic Platform for Cell Alignment(Springer Science and Business Media Deutschland GmbH, 2024) Yildirim-Semerci,Ö.; Arslan-Yildiz,A.Here, a PLLCL-on-chip platform was developed by direct electrospinning of poly (L-lactide-co-ε-caprolactone) (PLLCL) on polymethyl methacrylate (PMMA) microfluidic chips. Designed microchip provides the electrospinning of free-standing aligned PLLCL fibers which eliminates limitations of conventional electrospinning. Besides, aligned fiber structure favors cell alignment through contactless manipulation. Average fiber diameter, and fiber alignment was evaluated by SEM analyses, then, leakage profile of microchip was investigated. 3D cell culture studies were conducted using HeLa and NIH-3T3 cells, and nearly 85% cell viability was observed in PLLCL-on-chip for 15 days, while cell viability of 2D control started to decrease after 7 days based on Live dead and Alamar Blue analyses. These findings emphasize biocompatibility of PLLCL-on-chip platform for 3D cell culture and its ability to mimic extracellular matrix (ECM). Immunostaining results prove that PLLCL-on-chip platform favors the secretion of ECM proteins compared to control groups, and cytoskeletons of cells were in aligned orientation in PLLCL-on-chip, while they were in random orientation in control groups. Overall, these results demonstrate that the developed platform is suitable for the formation of various 3D cell culture models and a potential candidate for cell alignment studies. © The Author(s) 2024.Conference Paper 3d Printing-Assisted Fabrication of Microfluidic Pneumatic Valves(IEEE, 2023) Keleş, Şeyda; Karakuzu, Betül; Tekin, Hüseyin CumhurPneumatic valves have a crucial place in the fluidic control in microfluidic systems. Pneumatic valves containing polydimethylsiloxane (PDMS) membrane structures are used in microfluidic systems such as cell separation, and cell manipulation due to their flexible structure, and ease of production. This study demonstrates the rapid and straightforward fabrication of pneumatic valve structures using PDMS membranes, achieved through the utilization of 3D-printed molds. As a result of our experiments, we observed valve closure in a fluidic channel with a height of 150 μm. This closure was achieved by utilizing 400 μm × 800 μm PDMS membrane with a thickness of 66 μm positioned between the fluidic and control channels, while applying 1.5 bar of pressure to the control channel. When the pressure is removed, the opening time of the valve is only 0.02 s, and this response time allows rapid valving function. The presented valve fabrication strategy would allow easy and low-cost production of sophisticated microfluidic chips. © 2023 IEEE.Conference Object Serum Creatinine Detection in a Microfluidic Chip Using a Smartphone Camera(Chemical and Biological Microsystems Society, 2022) Karakuzu, B.; Tarim, E.A.; Tekin, H.C.We present a microfluidic chip platform to detect serum creatinine levels using the enzyme-linked immunosorbent assay (ELISA) principle. In the platform, surface modified microfluidic channel sensitively captured target molecules from the serum sample, and then ELISA protocol was applied inside the channels. Afterward, the blue color formed as a result of the enzymatic reaction was measured via a smartphone camera. The proposed strategy allows the detection of creatinine rapidly in a minute amount of the serum samples without the need for expensive equipment. Thus, chronic kidney disease (CKD) could be monitored easily at point-of-care settings via the proposed creatinine detection strategy. © 2022 MicroTAS 2022 - 26th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.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.Article Introducing Engineering Students To Microfluidics and 3d Printing Using Hands-On Activities(American Society for Engineering Education, 2023) Dogan, E.; Borgaonkar, A.D.; Nafisi, N.; Miri, A.K.Microfluidics technology involves the regulation of flow in micron-sized channels for desired reactions, with applications in biological modeling, drug manufacturing, screening of biological agents, and various engineering fluid dynamics-related purposes. Despite its growth and development, microfluidics has not been widely included as a teaching topic in undergraduate engineering education. This manuscript presents a hands-on project-based learning approach that can be easily implemented into core engineering courses, such as fluid mechanics, transport, chemical reactions, and others. Project-based activities presented here have three main parts: material preparation based on synthetic polymers, light-assisted manufacturing of a microfluidic device, and mass transport experiments to observe the fluid behavior. The project leverages 3D printing and the potential to connect students with makerspaces and 3D printing and to get them started on the path to bringing their ideas to life. The paper includes a breakdown of how to access and evaluate these activities. As a result of this hands-on activity, students will understand how fluid mechanics concepts are applied to microfluidics. Students will also learn about a novel interdisciplinary field that is growing rapidly. Engineering technology students will benefit from exposure to the application side of this emerging field through these lab-style activities that they are accustomed to in the majority of their core courses. Finally, the authors hope that such successful integration will encourage faculty to introduce other novel science and engineering topics that are currently only accessible through research experiencebased courses. © 2023, American Society for Engineering Education. All rights reserved.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: 9Citation - Scopus: 9Fabrication and Development of a Microfluidic Paper-Based Immunosorbent Assay Platform (μpisa) for Colorimetric Detection of Hepatitis C(Royal Society of Chemistry, 2023) Özefe, Fatih; Arslan Yıldız, AhuPaper-based microfluidics is an emerging analysis tool used in various applications, especially in point-of-care (PoC) diagnostic applications, due to its advantages over other types of microfluidic devices in terms of simplicity in both production and operation, cost-effectiveness, rapid response time, low sample consumption, biocompatibility, and ease of disposal. Recently, various techniques have been developed and utilized for the fabrication of paper-based microfluidics, such as photolithography, micro-embossing, wax and PDMS printing, etc. In this study, we offer a fabrication methodology for a microfluidic paper-based immunosorbent assay (μPISA) platform and the detection of Hepatitis C Virus (HCV) was carried out to validate this platform. A laser ablation technique was utilized to form hydrophobic barriers easily and rapidly, which was the major advantage of the developed fabrication methodology. The characterization of the μPISA platform was performed in terms of micro-channel properties using bright-field (BF) microscopy, and surface properties using scanning electron microscopy (SEM). At the same time, sample volume and liquid handling capacity were analyzed quantitatively. Ablation speed (S) and laser power (P) were optimized, and it was shown that one combination (10P60S) provided minimal deviation in micro-channel dimensions and prevented deterioration of hydrophobic barriers. Also, the minimum hydrophobic barrier width, which prevents cross-barrier bleeding, was determined to be 255.92 ± 10.01 μm. Furthermore, colorimetric HCV NS3 detection was implemented to optimize and validate the μPISA platform. Here, HCV NS3 in both PBS and human blood plasma was successfully detected by the naked eye at concentrations as low as 1 ng mL−1 and 10 ng mL−1, respectively. Moreover, the limit of detection (LoD) values for HCV NS3 were acquired as 0.796 ng mL−1 in PBS and 2.203 ng mL−1 in human blood plasma with a turnaround time of 90 min. In comparison with conventional ELISA, highly sensitive and rapid HCV NS3 detection was accomplished colorimetrically on the developed μPISA platform.Article Citation - WoS: 8Citation - Scopus: 11Cost-Effective and Rapid Prototyping of Pmma Microfluidic Device Via Polymer-Assisted Bonding(Springer, 2021) Sözmen, Alper Baran; Arslan Yıldız, AhuMicrofluidic systems are relatively new technology field with a constant need of novel and practical manufacturing materials and methods. One of the main shortcomings of current methods is the inability to provide rapid bonding, with high bonding strength, and sound microchannel integrity. Herein we propose a novel method of assembly that overcomes the mentioned limitations. Polymer-assisted bonding is a novel, rapid, simple, and inexpensive method where a polymer is solubilized in a solvent and the constituted solution is used as a bonding agent. In this study, we combined this method with utilization of several phase-changing materials (PCMs) as channel-protective agents. Glauber's salt appeared to be more suitable as a channel-protective agent compared to rest of the salts that have been used in this study. Based on the bonding strength, quality analyses, leakage tests, and SEM imaging, the superior assisting bonding solvent was determined to be dichloromethane with a PMMA concentration of 2.5% (W/V). It showed a bonding strength of 23.794 MPa and a nearly non-visible bonding layer formation of 2.83 mu m in width which is proved by SEM imaging. The said combination of PCM, solvent, and polymer concentration also showed success in leakage tests and an application of micro-droplet generator fabrication. The application was carried out to test the applicability of developed prototyping methodology, which resulted in conclusive outcomes as the droplet generator simulation run in COMSOL Multiphysics version 5.1 software. In conclusion, the developed fabrication method promises simple, rapid, and strong bonding with sharp and clear micro-channel engraving.