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Organic photovoltaic (OPV) cells are devices that convert solar energy into electrical energy using organic materials. A promising material for improving the efficiency of OPV cells is magnetite, also known as iron oxide (Fe 3 O 4 ), which acts as a semiconductor with high electrical conductivity. In this study, Fe 3 O 4 magnetite nanoparticles were initially synthesized and incorporated into the hole transport layer (HTL) of the OPV, which consists of poly(3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS), a conductive polymer blend. It is well known that the efficacy of OPV cells is significantly affected by the preparation conditions, including the magnetite content and thickness of the active layer. To investigate the effect of magnetite on OPV cell efficiency, varying amounts of magnetite were added to the organic layer. A comparative analysis was performed between doped PEDOT:PSS (PEDOT:PSS with added magnetite) and pristine PEDOT:PSS (a reference sample without magnetite). Characterization studies were carried out using various techniques such as FTIR (Fourier Transform Infrared Spectroscopy), AFM (Atomic Force Microscopy) and UV transmittance measurements. These analyzes aimed to gain insight into the structural, morphological and optical properties of doped and undoped layers, providing a deeper understanding of how magnetite affects the performance of OPV cells.

With the increasing population, there are important studies in foodpackaging so as to provide efficient use of food sources, to meet customers'needs, and to prevent environmental pollution. Edible films and coatings arebiocompatible polymeric materials, which offer solution to the problems causedby synthetic packaging. They are used to increase shell life and to preventquality loss in food. Herbs, which are natural antioxidant sources due to theirhigh phenolic compounds, are often preferred as additives in polymeric filmproduction. Laurel (Laurus nobilis), besidesits widespread use as a spice, is one of the most beautiful characteristicplants of places with Mediterranean vegetation, whose native land is Anatolia.It also has antibacterial, antiviral, insectiside, antiseptic and antioxidantproperties. Carboxymethyl cellulose is one of the most commonly used cellulosederivatives in the food industry due to its thickener, gelling, stabilizer,emulsifier and bulking properties in the GRAS (generally recognized as safe)status. Due to its high molecular weight and viscosity, it was preferred in thepreparation of films in our study. In this study, carboxymethylcellulose (2%w/v) based edible films containing laurel leaf extract were prepared by solventcasting method. The dried and ground laurel leaves were extracted with theSoxhlet Apparatus for 6 hours in a mixture of ethanol: water (80:20,v/v) andthen their solvents were removed by rotary evaporator. Total phenolic contentsand antioxidant capacity of the films were determined using Folin-Ciocalteu and2,2-Diphenyl-2-picrylhydrazil (DPPH) radical scavenging methods, respectively.Antimicrobial activity was determined by agar diffusion method on Staphylococcus aureus (ATCC 25923), Escherichia coli (ATTC 25922) and Candida albicans (ATTC 10231). Theminimum inhibition concentration value (MIC) of the films was found to be 313μg/ml. Additionally, the thickness, solubility, water vapor permeability and %swelling ratio of edible films were investigated. The functional groups of theprepared films were characterized by Fourier Transform Infrared Spectroscopy(FTIR), their thermal properties by Differential Scanning Calorimetry (DSC),and their surface properties by Scanning Electron Microscopy (SEM). As aresult, it has been found that CMC edible films containing laurel extract withantioxidant and antimicrobial properties have a great potential to reduce foodwaste and environmental pollution, and to increase food quality and safety.

Polimerler, implantlar, ilaç kaplama malzemeleri,protez ürünler, cerrahi araçlar gibi pek çok tıbbi alanda kullanılmaktadır. Bumalzemelerdeki en tehlikeli sıkıntılardan biri mikroorganizmakontaminasyonudur. Bu sebeple medikal alanlarda kullanılan malzemelerinantimikrobiyal özellik taşıması istenmektedir. Sentetik antimikrobiyallerinkolay elde edilebilirliği ve yüksek etkinliği ile sıklıkla tercih edilmiştirFakat bu sentetik antimikrobiyallerden kaynaklanan antimikrobiyal dirençlilikgibi ciddi sıkıntılar daha güvenilir ve doğal kaynaklı antimikrobiyal ajanlarayönelmeye neden olmuştur. Bitkiler sahip oldukları içerikler ile asırlardırhastalıkların önlenmesi ve tedavisinde kullanılmaktadırlar. Nane, içermişolduğu zengin fenolik bileşikler sayesinde güçlü bir antimikrobiyal özelliğesahiptir. Yapmayı planladığımız projede ülkemizdeki kaynaklardan temin edilennane örneğinde ekstrakte edilen özüt ile biyopolimer film elde edilerekantimikrobiyal etkinliği analiz edilecektir. Analizler sonucunda elde edilenürünün biyomalzeme olarak kullanılabilirliği araştırılacaktır.

This study presents that the controlled release of Hypericum perforatum (HP) from biofilm formation of sodium alginate (NaAlg). Its oil was incorporated in sodium alginate biofilm as a potential therapeutic agent. HP belongs from the family of Hypericaceae. HP is traditionally used for wound healing in Turkey and has medical importance. In addition, bacterial resistance of HP was investigated for against Staphylococcus aureus. Silver Sulfadiazine (SSD) was added in different concentration (0.5-2.0 w/v) to prepare the antibacterial biofilms. The addition of antibiotics and HP into the biofilm will ensure the delivery of all the necessary substances locally in the wound healing process. Biofilms were prepared by solvent casting method in different oil concentration (0.25-2.0 % v/v). The surface properties of biofilms were investigated by using Scanning Electron Microscopy (SEM), drug release profiles were studied at pH 5.5 and bacterial resistance of HP was investigated for against Staphylococcus aureus. As a result of our study, the new generation hydrogel wound dressing will, heal wounds effectively and quickly especially protecting the burns from microorganisms.

Bu çalışmada, Teofilin’i(TF) kapsüllemek üzere poli (vinil alkol)(PVA)/ sodyum karboksi metil selüloz (NaCMC) mikroküreler hazırlandı. Mikroküreler emülsiyon çapraz bağlama yöntemi kullanılarak demir III klorür(FeCL3) ile çapraz bağlanarak oluşturuldu. Hazırlanan mikrokürelerin fourier transform infrared(FTIR) spestroskopi, diferansiyel tarama kalorimetri (DSC), taramalı elektron mikroskopisi(SEM) ve X-ışını kırınımı(XRD) ile karakterizasyonu belirlendi. Mikroküreler ayrıca denge şişme değerleri ve salım profilleri ile de tanımlandı. Salım çalışma ortamının pH değeri 7,4’de sabit tutuldu. PVA/NaCMC oranının, ilaç/polimer (i/p) oranının ve çapraz bağlama süresinin tutuklama verimi ve TF salımı üzerine etkisi incelendi. Salım şartlarından PVA/NaCMC oranı 1/2 (m/m), i/p oranı 1/8 olan, 0,3 M FeCl3 ile 30 dakika süre ile çapraz bağlanan mikrokürelerde %98 verim ile en iyi sonuca ulaşıldığı belirlendi In this study, poly (vinyl alcohol) (PVA) / sodium carboxy methyl cellulose (NaCMC) microspheres were prepared to encapsulate theophylline (TF). Microspheres were formed by cross-linking with iron III chloride (FeCl3) using emulsion crosslinking method. Fourier transform infrared (FTIR) spestroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were determined. Microspheres were also defined by equilibrium swelling values and release profiles. pH of the working environment was kept constant at 7,4. The effect of PVA / NaCMC ratio, drug/polymer (i/p) ratio and crosslinking time on arrest efficiency and TF release was examined. It was determined that the best results were achieved with 98% efficiency in crosslinked microspheres with 0,3 M FeCl3 with PVA / NaCMC ratio of 1/2 (m / m) and i / p ratio of 1/8 (m / m).

Bu çalışmada; Nonsteroid Antiinflamatuvar İlaçlar (NSAİİ) grubunda yer alıp ağrı kesici bir ilaç olan Ketorolak Trometamin'in (KT) kontrollü salımı gerçekleştirildi. Bu amaçla KT, sodyum karboksimetil selüloz (NaCMC) / polivinilpirolidon (PVP) biyouyumlu polimerleri ile kapsüllenerek mikroküreleri hazırlandı. su/yağ/su emülsiyon çapraz bağlama yöntemiyle çapraz bağlayıcı ajanı FeCI3 kullanılarak mikroküre oluşumu gerçekleştirildi. Mikrokürelerde; polimer/polimer oranı, ilaç/polimer oranı ve çapraz bağlayıcı süresi pH 7,4 değerinde KT salımı üzerine etkisi incelendi. En iyi KT salım koşulu, PVP/NaCMC oranı 1/2, ilaç/polimer oranı 1/1 ve 0,31 M FeCI3 ile 30 dk. çapraz bağlanan mikrokürelerde %81,1 olarak gerçekleştiği tespit edildi. Ayrıca mikrokürelerde denge şişme değerleri, tutuklama verimi, ilaç yükleme kapasitesi, çapraz bağlayıcı yoğunlukları tanımlandı. Çalışmanın ikinci kısmında ise en iyi orana sahip mikroküreler farklı kalınlıklarda etilselüloz (EC) matriks filmi ile kaplandı. EC kalınlığının KT salımı üzerine etkisi incelendi. Hazırlanan mikroküreler ve etilselüloz kaplı mikroküreler Fourier Transform Infrared Spektroskopi (FTIR), Diferansiyel Tarama Kalorimetri (DSC), Taramalı Elektron Mikroskopisi (SEM) ve X-Işını Kırınımı (XRD) ile karakterize edildi. In this study; controlled release of Ketorolac Tromethamine (KT) which is a painkiller that is in the group of Nonsteroidal Anti-inflammatory Drugs (NSAIDs) was performed. For this purpose, microspheres were prepared by encapsulated KT with sodium carboxymethyl cellulose (NaCMC) / polyvinylpyrrolidone (PVP) biocompatible polymers. Microsphere formation was carried out by water/oil/water emulsion crosslinking method using crosslinker agent FeCI3. Polymer /polymer ratio, drug/polymer ratio and crosslinking time at pH value 7,4 were examined on KT release effect in the microspheres. The best KT release condition was found to be 81,1% for the microspheres prepared by PVP/NaCMC ratio of 1/2 (w/w), drug /polymer ratio of 1/1 (w/w) crosslinked with 0,31 M FeCI3 for 30 minutes. In addition, equilibrium swelling values, entrapment efficiency, drug loading capacity and crosslinking density were examined in the microspheres. In the second part of the study, the microspheres which had the best ratio were coated with different thickness of ethylcellulose (EC) matrix film. The effect of EC thickness on KT release was investigated. The prepared microspheres and EC coated microspheres were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD).