Master Degree / Yüksek Lisans Tezleri

Permanent URI for this collectionhttps://hdl.handle.net/11147/3008

Browse

Filters

2016 - 201922020 - 20212

Settings

Subject: search.filters.subject.Fluorescent probes

Search Results

Now showing 1 - 4 of 4
  • Master Thesis
    Fluorescent Gold Ion Sensors: Design, Synthesis and Imaging
    (01. Izmir Institute of Technology, 2021) Kaya, Beraat Umur; Emrullahoğlu, Mustafa
    Of all transition metals, gold has long sustained attention owing to its unique chemical and physical properties. Beyond that, the ease of processing gold allows its use in science, industry, and in various chemical, biological, and medical applications. For example, gold is used in medicine to treat rheumatoid arthritis, asthma, cancer, and brain and skin lesions. However, the extensive use of gold compounds can adversely impact the natural environment and biological systems due to their potential toxicity. For those reasons, identifying trace amounts of gold species in solution and cell media is crucial. Unlike the detection methods of atomic absorption spectroscopy, atomic emission spectroscopy, and inductively coupled plasma spectrometry, fluorescence-based detection methods offer easy sample preparation, rapid response, high sensitivity, reproducibility, and efficiency, all at a low cost. Today, various types of fluorescent sensors selective to gold ions have been designed, typically with BODIPY, fluorescein, rhodamine, naphthalimide, and coumarin-based fluorophores. In the work for this thesis, for the first time an enyne-derived BODIPY-based sensor was designed and synthesised to identify Au3+ ions, after which photophysical changes in the presence and absence of the analyte were examined both in solutions and in cells.
  • Master Thesis
    Design and Synthesis of a Bodipy Based Probe for Cadmium Ions
    (01. Izmir Institute of Technology, 2021) Cebeci, Miray; Emrullahoğlu, Mustafa
    Given the severely toxic effects of heavy metals on living systems and the environment in general, identifying and quantifying heavy metal ions in synthetic samples and in vivo are highly significant activities. One such heavy metal, cadmium, allows only a low level of tolerable exposure and can thus have fatal consequences or cause critical health problems such as ostial disorders, nephrotic syndromes, various types of cancer even in extremely low concentrations. Although several standard techniques for detecting cadmium have been used, including atomic absorption and emission spectroscopy and inductively coupled plasma mass spectrometry, all of them require complex instruments that are also expensive, time-consuming to use, and hardly portable. For that reason, sensitive, selective, less labour-intensive methods of detecting cadmium ions are greatly needed. In response, fluorogenic or chromogenic methods afford high analyte sensitivity and selectivity, easy sample preparation, and easy monitoring, all with affordable instrumentation. Against that background, this thesis reports the design, synthesis, and development of a fluorescent molecular sensor that can detect Cd2+ ions within spectroscopic behavior and living cells. In the design, based on the mechanism of intramolecular charge transfer (ICT), borondipyrromethene (BODIPY) dye was used as a signal reporter due to its unique properties, and di-(2-picolyl)amine (DPA) was chosen to represent the recognition unit. Altogether, the sensor offers rapid response, high selectivity, and high sensitivity in detecting Cd ions is reversible with the aid of CN- and can be used to efficiently image Cd2+ species in vitro.
  • Master Thesis
    Design and Synthesis of Phosphine Based Fluorescent Probes for Reactive Oxygen Species
    (Izmir Institute of Technology, 2018) Üçüncü, Canan; Emrullahoğlu, Mustafa; Emrullahoğlu, Mustafa
    Hypochlorous acid is a cleansing agent known as bleach in daily life. Apart from the household chemicals feature, HOCl plays an active role in the defence system of living cells. It is an important reactive oxygen species that exhibits anti-microbial properties against invaders. However, the increase in the amount of cells in the cell due to oxidative stress causes serious damage to the structure and function of the organism and can cause fatal diseases. Determination of reactive oxygen species in the cell is of great importance. Although different detection methods are used for this purpose, fluorescent sensors are preferred for their precision, easy preparation, high resolution, and quick response. In this study, a "turn on" probe has been designed to detect HOCl based on these reasons. Anthracene dye has been found to be non-fluorescent due to PET when derivatized with phosphorus. In the presence of HOCl, it was determined that the phosphorus was oxidized, inhibiting PET and causing fluorescent radiation. The aim of this thesis is to examine the spectroscopic analysis of the probe which is developed as sensitive to HOCl in various ways and to display the presence of HOCl in the living cell.
  • Master Thesis
    Desing and Synthesis of Fluorescein Based Gold Ion Sensors
    (Izmir Institute of Technology, 2016) Çetintaş, Ceyla; Emrullahoğlu, Mustafa
    Gold has been a part of people’s lives for ages and is used as money, goods and jewellery. In recent years, gold has played a key role in chemistry, medicine and biology. Since the 1970s, gold has been extensively used as a catalyst in several chemical transformations. Due to its high biocompatibility, functionalized gold nanoparticles have been extensively employed as drug and gene delivery systems, biosensors and bio-imaging materials. However, gold complexes can become toxic to the human body by interacting with biomolecules such as DNA and enzymes. Therefore, detection of trace amounts of gold species is an important issue and can be achieved via spectroscopic methods such as atomic absorption spectroscopy, atomic emission spectroscopy and inductively coupled plasma spectrometry. However, these analytical methods require complicated sample preparation steps and sophisticated instrumentation. In contrast to these extremely expensive and time-consuming methods, fluorogenic or chromogenic methods, which provide high analyte sensitivity and selectivity, can serve as good alternatives for detecting gold species. To develop new probes for the detection of Au3+ ions, we focused on the design of new fluorescein-based probes that are soluble in aqueous media. We aimed to investigate the in vivo activity of these fluorescent probes. In the proposed detection system, gold ions are expected to mediate a chemical reaction through coordination to an alkyne moiety that results in a ring opening reaction to yield a highly fluorescent derivative.