Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
Browse
3 results
Search Results
Master Thesis Development and Characterization of Biomimetic Peptide-Based Bioink for Dental Tissue Engineering(01. Izmir Institute of Technology, 2023) Arslan Yıldız, Ahu; Arslan Yıldız, Ahu; 03.01. Department of Bioengineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyRecently, the role of molecular control in the tooth mineralization process has received much attention. Biomimetic scaffolds have been started to use in dental tissue engineering and regeneration due to their high applicability, biocompatibility, biodegradability, and mineralization capability. In this thesis, a hybrid biomimetic bio-ink; P11-4 peptide-based Quince Seed Hydrogel (QSH)/Gelatin (Gel) is used in 3D cell culture studies for dental tissue engineering applications. Pristine QSH, QSH/Gel, and P11-4/QSH/Gel bio-inks were characterized by FTIR and viscosity analysis, and their 3D bioprinting parameters were optimized. Hydrogels were crosslinked via 1-Ethyl-3-(3-dimethylaminopropyl) Carbodiimide (EDC)/N-Hydroxysuccinimide (NHS) coupling reaction and various hydrogel concentrations were investigated for scaffold fabrication. Characterization of produced scaffolds was performed by SEM imaging, mechanical testing, protein adsorption, and swelling analyses. As a result, the mechanical strength, viscosity, swelling properties, and surface characteristics of the biomaterial were evaluated. SaOS-2 human osteosarcoma cell line was used for 3D bioprinting studies. Cell viability analyses were performed via Live/Dead and MTT assays. Mineralization was investigated and assay was carried out with Alizarin Red Staining. According to obtained results, P11-4/QSH/Gel scaffolds provide high cell viability and proliferation rate compared to pristine QSH and QSH/Gel control groups. Also, with the addition of P11-4 to QSH/Gel, a certain amount of increase in mineralization was observed after day 7 on long-term cultured scaffolds. As a result of this study, it was concluded that P11-4-based QSH/Gel has a high potential to be used as a bio-ink in the production of 3D scaffolds for dental tissue engineering applications.Master Thesis Development and Characterization of Magnesium Alginate Hydrogels for 3d Cell Culture Formation(01. Izmir Institute of Technology, 2021) Arslan Yıldız, Ahu; Çoban, Başak; Arslan Yıldız, Ahu; 01. Izmir Institute of Technology; 03.01. Department of Bioengineering; 03. Faculty of EngineeringCell culture is an important tool for biological research. Two-dimensional (2D) cell culture is still used but growing cells on plastic surfaces offering unnatural growth kinetics and cell attachment. Three-dimensional (3D) cell culture allows cells to growth in their 3D physical shape and interact with their surroundings which represent the natural microenvironment. Hydrogels are crosslinked networks, have become increasingly used biomaterial for 3D cell culture with their ability to simulate the nature of most soft tissues. In this thesis, a new methodology based on bio-patterning was developed to fabricate (3D) cellular structures by using Mg-alginate hydrogel and fabricated 3D cellular structures was utilized for drug screening studies. Mg-alginate hydrogel has a specific gelation/de-gelation characteristics compared to other types of hydrogels due to its weak polymer-ion interaction. In this study slow gelation and de-gelation property of Mg-alginate hydrogel was used for biopatterning of 3D cellular structures. Plackett-Burman and Box-Behnken design models were used to optimize parameters of Mg alginate-based biopatterning method while using HeLa cells as a model cell line. Then, the applicability of newly developed methodology was successfully demonstrated by using SaOS-2 and SH-SY5Y cells to fabricate 3D cellular structures. Cell proliferation and migration profiles were observed during long-term culturing with time-dependent light microscopy images. Also cell proliferation and viability of long-term cultured tumor models were analyzed by using Alamar Blue and Live/Dead assays. Moreover, F-actin, Collagen I, and DAPI staining/immunostaining was done to investigate cellular and extracellular components of 3D cellular structures for short and long-term culture times. Finally, the dose-response of fabricated 3D structures was evaluated and compared with standard 2D cell culture by applying doxorubicin (DOX). The IC50 values were calculated for 3D cellular structure of HeLa, SaOS-2 and SH-SY5Y cells as 8.2, 7.8, and 2.1 µM respectively while IC50 values of 2D controls obtained as 3.2, 4.4, and 0.2 µM respectively. These results were also statistically analyzed and dose responses were found significantly different according to t-test, which means 3D cellular structures were more resistant to drug exposure compared to 2D cell culture.Master Thesis Design and Development of Paper-Based Microfluidics for Point-Of Applications(01. Izmir Institute of Technology, 2020) Özefe, Fatih; Yıldız, Ümit Hakan; Özefe, Fatih; Arslan Yıldız, Ahu; Arslan Yıldız, Ahu; Yıldız, Ümit Hakan; 01. Izmir Institute of Technology; 04.01. Department of Chemistry; 03.01. Department of Bioengineering; 03. Faculty of Engineering; 04. Faculty of SciencePaper-based microfluidics is a subarea of microfluidics which is recently used in various applications from diagnostics to environmental monitoring, and to food safety. In such microfluidic systems, a test platform is formed from a paper substrate instead of silicon and polymers, such as poly-dimethylsiloxane, poly-methyl methacrylate, and etc. The main goal of this thesis is the development and fabrication of a paper-based microfluidic device (μPAD), which could be used in point-of-care (POC) applications. The characterizations of μPADs, which were fabricated via laser ablation methodology, were performed in terms of their surface and barrier characteristics, and liquid sample flows within μPADs. Depending on the characterization, nine different fabrication parameters, 10P40S (10%Power & 40%Speed), 10P60S, 20P90S, 30P50S, 30P100S, 40P80S, 40P100S, 70P80S, and 70P100S, were identified as optimized fabrication parameters. Also, two designed models of μPADs, 1S4T-Type2 and 1S4T-Type3, were selected to be used in the detection of BSA and recombinant Hepatitis C Virus (HCV) protein. The BSA and HCV (1 mg/ml) in PBS solution were successfully detected via naked eye depending on the colorimetric sensing through micro-paper enzyme linked immunosorbent assay (μP-ELISA) protocol. Moreover, the limit of detection (LoD) values for HCV were determined in 1S4T-Type2 μPAD as 1.000, 0.883, and 0.796 ng/ml when the detection was performed via naked eye, smart-phone, and bright-field microscope, respectively. Also, the easily-disposable 1S4T-Type2 μPAD provided 14 times faster and 45 times cheaper detection of HCV compared to conventional ELISA techniques. Consequently, the developed 1S4T-Type2 μPAD presented low-cost, easy-to-use, and rapid detection of HCV as POC devices.