Kimya Mühendisliği Bölümü Koleksiyonu

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https://hdl.handle.net/20.500.13055/46

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The use of copper phthalocyanine pigments as blue colorants in gelatin films for aquatic food packaging
(Kocaeli University, 2025) Bayıl, Sibel; Çetinkaya, Turgay; Alanalp, Mine Begüm
In this study, Copper (Cu) phthalocyanine pigments, coded PD1 and PD2, were characterized, and the possibility of using them as blue colorants in gelatin-based materials for aquatic packaging was evaluated. Synthesized phthalocyanine pigments were compared with imported commercial PB15:1 (control) in terms of Fourier Transform Infrared Spectroscopy (FTIR), high-performance liquid chromatography (HPLC) results, Cu, and ash content. It was found that the synthesized PD1 and PD2 samples were the ones closest to the commercial powder in terms of FTIR peaks, Cu amount, and HPLC results. The selected sample coded PD1 at 0.5 wt% with respect to the solution was further added to gelatin-containing solutions containing 10% and 5% glycerol, and dried films of GL10 and GL5 were obtained, respectively. Although the 10% glycerol-added film showed better color properties, L, a, b, Hue angle, and Chroma parameters were insignificant (p>0.05). Tensile tests and creep/recovery curves showed that GL10 had 107% higher elongation at break, 29% lower Young’s modulus, and higher strain values compared to GL5, making it softer and more flexible. Deformation parameters such as hardness, chewiness, and gumminess were also compared at different deformation rates for the selected GL10 sample. Results indicated that blue pigment-added gelatin films can be used in aquatic food product packages.
Efficient and facile synthesis of hydroxy-functionalized hexagonal boron nitride nanosheets by ion-assisted liquid phase exfoliation method
(Eskişehir Osmangazi University, 2025) Yaman Uzunoğlu, Gülşah
Hexagonal boron nitride (h-BN) nanosheets have attracted significant attention due to their unique mechanical, thermal, and electronic properties. Their biocompatibility, thermal conductivity, chemical stability, and versatility make them indispensable in cutting-edge technologies. Hydroxy-functionalized h-BN nanosheets (h-BNNS-OH) exhibit immense potential in various applications, including electrochemical energy storage, drug delivery systems, and heat spreaders in thermal management systems. This study focuses on the hydrothermally ion-assisted liquid-phase exfoliation of h-BN powder to produce few-layer h BNNS-OH. The exfoliation process involves hydrothermal treatment of bulk h-BN in the presence of concentrated aqueous solution of KOH and NaOH at 180 °C, followed by sonication for dispersion of h-BNNS-OH in water. Characterization of h-BNNSs was performed using powder X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The resulting exfoliated h-BNNSs are hydroxyl-functionalized on their surface. This study demonstrates the effectiveness of the successive execution of the hydrothermal treatment in the presence of excess alkali metal hydroxides and probe sonication as a facile and efficient exfoliation process, resulting in dispersions of h-BNNS-OH in water with remarkably high stability (beyond 9 weeks) and high product yield (17 %) at only one exfoliation cycle.
Impact of extraction solvents on total antioxidant capacity of barberry (berberis crataegina) plant
(Sivas Cumhuriyet University, 2025) Özdemir Olgun, Fatoş Ayça; Demirata Öztürk, Birsen
Defense mechanisms involving antioxidant molecules play a key role in neutralizing free radicals formed in the human body. It is important to determine the content of these molecules, which have become important in human nutrition in recent years, in consumed foods. This study aims to determine the total antioxidant capacity of the barberry (Berberis Crataegina) plant, which is consumed in many regions of Turkiye. For this purpose, firstly, barberry plant samples were collected from Mersin in summer season, the extracts were prepared with different solvents and CERAC method was used to determine the total antioxidant capacities of the samples. The highest value of total antioxidant capacity was obtained by 80 % (v/v) methanol solution for flesh part of the fruit. Total phenolic compound and total antioxidant capacities of the flesh part of barberry samples were calculated as 1.954 mmol gallic acid (GA) g-1 and 1.288 mmol Tr (TR) g-1, by Folin-Ciocalteu method and Cerium Reducing Antioxidant Capacity Assay (CERAC), respectively.
Energy production from gas hydrates
(Elsevier, 2025) Çifci, Günay; Parlaktuna, Mahmut; Çelebi, Serdar Suut; Okay Günaydın, Seda
Gas hydrates are a type of natural formation that contains large amounts of mostly methane, which is also known as natural gas, and water, in the form of ice. Methane hydrates are cages of water molecules that surround and trap methane molecules. Gas hydrate is geophysical, geologically and economically important for several reasons: Gas hydrates are good cap rocks for oil and natural gas. The methane hydrate itself is an important energy source. A volume of gas hydrate can store up to 164 times per volume of gas as zipped gas, and the fact that gas hydrate occurs almost all around the world. Methane seepage may indicate the existence of a deeper hydrocarbon reservoir, and the methane production and migration in the slope sediments may cause massive slope failure. Last but not least Methane gas has a minimum 22 times more global warm absorption capacity compared to carbon dioxide if it is released into the atmosphere. In other words, greenhouse gas is due to its contribution to climate change. Gas hydrates have drawn significant interest as a potential near future energy resource. Research in the production field of gas hydrates has focused on several key areas, including the feasibility of commercial production, the environmental impacts, and the technological improvements associated with the safe recovery of gas.
Management of plastic wastes: History, current applications, and future perspectives of recycling, upcycling, and reclaiming technologies
(Springer Nature Link, 2026) Alanalp, Mine Begüm; Ergin, Mustafa Fatih; Durmuş, Ali; Das, Alok Prasad; Karakuş, Selcan
Plastic materials possess a variety of structural and physical features and some key characteristics that make them widely used in many applications due to their superior properties such as low density, chemical and mechanical durability, low cost, recyclability, easiness and versatility in processing, thermal and electrical insulating property, colorability. Plastics are used in various applications in many industrial areas and daily-life, including packaging (the largest segment), construction, automotive, electronics, and consumer goods. Since the 1950s, production and consumption of plastics has readily increased, with global production reaching over 370 million metric tons in recent years. This trend is expected to continue, with projections estimating it could reach over 1 billion metric tons by 2030. The highest plastic consumption is found in developed regions like North America, Europe, and parts of Asia. However, emerging economies are rapidly increasing their consumption related to growing industrialization and urbanization in these countries. Overall, while plastics play a crucial role in modern society, their increasing consumption raises important questions about sustainability and environmental health. The rapid increase in plastic production and consumption has led to significant environmental challenges such as pollution, wildlife harm, and waste management issues. An estimated 11 million metric tons of plastic enter the oceans each year. There is a growing push toward a circular economy model, emphasizing the importance of reducing, reusing, and recycling plastics to minimize environmental impact. Managing plastic wastes effectively involves a combination of various strategies aimed at reducing, reusing, recycling, and disposing of plastics in an environmentally responsible manner. Modern societies can significantly reduce plastic waste and its environmental impact, promoting a more sustainable future by integrating these strategies. This chapter comprehensively summarizes and discusses the current applications of recycling, upcycling and reclaiming technologies of plastic wastes. Future perspectives and projections will also be highlighted to manage plastic wastes effectively and establish sustainable development in the world.
Redox-responsive and mucoadhesive nanoparticles: An overlooked synergy in modern drug delivery
(Elsevier, 2026) Küçükertuğrul Çelik, Sibel; Şentürk, Sema; Bal, Kevser; Kaplan, Özlem; Gök, Mehmet Koray
The continuous advancement of therapeutic technologies has intensified the pursuit of drug delivery systems that respond intelligently to physiological and pathological stimuli, thereby enabling precise, localized, and sustained therapeutic outcomes. Among redox-based approaches, systems responsive to intracellular glutathione (GSH) have attracted particular attention due to their ability to trigger disulfide bond cleavage and controlled release within diseased tissues. Mucoadhesive systems, on the other hand, prolong residence time on mucosal surfaces through non-covalent interactions and covalent bond formation, thereby facilitating increased absorption and decreased clearance. Despite their individual successes, the integration of these two mechanisms remains underexplored. This review critically examines the coupling of redox sensitivity and mucoadhesion, highlighting how disulfide-based bonds can simultaneously function as both redox-cleavable and mucoadhesive moieties.
Flaxseed-based green electrolyte enabling high electrochemical stability for advanced zinc ion batteries
(Wiley, 2026) Arıkan, Yiğit Berke; Kömürcüoğlu, Gökçe; Adhami, Sadaf; Yaman Uzunoğlu, Gülşah; Yüksel, Recep
This study presents a green and sustainable electrolyte derived from flaxseeds (FS) aimed at enhancing the electrochemical stability of zinc-ion batteries (ZIBs), thereby reducing the occurrence of free water molecules and alleviating the hydrogen evolution reaction (HER) that contributes to the development of zinc (Zn) dendrites. The abundant hydroxyl groups present in polysaccharides and phenolic compounds within the flaxseeds coordinate with Zn2+, modifying the solvation sheath and reducing HER activity. Zn//Zn symmetric cells utilizing the FS-based electrolyte exhibited remarkably stable cycling for 3000 h at a current density of 1.0 mA cm−2 (1.0 mAh cm−2) and 2500 h at 2.0 mA cm−2 (2.0 mAh cm−2). Zn//V2O5 full cells delivered a discharge capacity of 233.8 mAh g−1 at 0.2 A g−1 and excellent rate capability across a wide current density range of 0.2–10 A g−1 . The ex situ SEM and XRD results confirmed uniform Zn deposition along the (002) plane without dendrite formation. This work demonstrates a biomass-derived, low-cost electrolyte formulation strategy that effectively stabilizes Zn interfaces, providing a green and efficient pathway for next-generation zinc-ion batteries.
Waste toner particles based dispersive solid phase extraction for the trace determination of cadmium in cinnamon tea samples by flame atomic absorption spectrometry
(Elsevier, 2026) Ali, Büşra; Büyük, Muhammed Ali; Bayraktar, Ahsen; Serbest, Hakan; Bakırdere, Sezgin
This study presents a dispersive solid phase extraction (DSPE) protocol for the sensitive and accurate determi nation of trace levels of cadmium ions (Cd2+) by flame atomic absorption spectrometry (FAAS). Toner particles obtained from used printer cartridges were used as sorbent material for preconcentration of Cd2+ ions. Opti mization studies were performed univariately for the achievement of the highest extraction efficiency and the limit of detection (LOD) was found to be 0.55 µg L-1 under optimal operating conditions. By comparing the slopes of the linear plot equations for FAAS and waste toner-based DSPE-FAAS systems, the increase in sensitivity was calculated to be 40.9 times. The feasibility of the developed method was evaluated by spiking recovery studies on cinnamon tea samples and good recovery results between 90.4 % and 119.0 % determined by the matrix matching calibration strategy showed that the method is applicable to cinnamon tea and similar matrices.
Optimization of VA-NADES-ME for the one-step separation and determination of rhodamine B and rhodamine 6G in red pencil samples
(Taylor & Francis, 2025) Topraksever, Nükte; Özgül Artuç, Gamze
An environmentally friendly and simple method was developed for the simultaneous separation and determination of Rhodamine B (RhB) and Rhodamine 6 G (Rh6G) in red pencil samples by vortex assisted microextraction using NADES (Natural Deep Eutectic Solvent). A two-phase system was established using lactic acid-based DES (Deep Eutectic Solvent) and tetrahydrofuran (THF) for the extraction of RhB and Rh6G. In method optimization, sample amount, pH, DES type, DES volume, solvent type and solvent volume parameters were investigated. Limit of detection (LOD) and limit of quantification (LOQ) values were 4.13, 5.03 and 12.5, 15.3 µg/mL for RhB and Rh6G, respectively. The correlation coefficients obtained at concentrations ranging from 1–12 µg/mL are 0.9973 and 0.9985. Red pencil samples were spiked at two different concentrations (3–5 µg/mL). The recovery values obtained were in the range of 84.7%-107.4%. The relative standard deviation (RSD) values of the developed method are in the range of 2.77%-5.45%, indicating that the method is reproducible. The results showed that the developed microextraction method can be success fully applied for the separation and determination of RhB and Rh6G from red pencil samples.
Quantitative determination of α-tocopherol and α-tocopheryl acetate in pharmaceutical and supplementary soft capsules by high performance liquid chromatography
(İstanbul Gelisim University, 2025) Topraksever, Nükte; Özgül Artuç, Gamze
Aim: This study aims to determine the amounts of α-tocopherol (α-toc) and α-tocopheryl acetate (α-tocAc) in soft pharmaceutical capsules and supplements using a chromatographic method. Additionally, method validation parameters for both analytes were evaluated. Method: Analyses were performed using a chromatographic method. As part of the method validation, recovery (% recovery), repeatability (% RSD), linear regression coefficient (R²), limit of detection (LOD), and limit of quantification (LOQ) values were determined. Results: The recovery values were found to be above 95%. Repeatability (%RSD) was calculated as <3%. The linearity (R²) values were obtained as 0.999. For α-toc: LOD: 0.131 µg/mL and 2.228 µg/mL, LOQ: 0.396 µg/mL and 6.752 µg/mL. For α-tocAc: LOD: 0.260 µg/mL, LOQ: 0.787 µg/mL. Conclusion: The chromatographic method used in this study enabled the determination of α-toc and α tocAc with high accuracy and repeatability. This method can be considered a reliable alternative for the analysis of these compounds in pharmaceutical products.
Phocatalytic dye degradation activities of chitosan film modified by green synthesized tio2 from aloe vera leaf extract
(Avestia Publishing, 2025) Kaba, İbrahim; Bozkurt, Rabia Nur; Kerkez Kuyumcu, Özge; Koca, Atıf
Recent research focuses on heterogeneous photocatalysis, an environmentally friendly and cost-effective method that uses solar energy to completely degrade pollutants without generating secondary waste. The focus is optimizing the properties of photocatalysts in terms of electronic structure, light absorption, and reduced recombination rate of photogenerated charges and easy separation of the photocatalyst from reaction media [1]. The potential for efficient, sustainable heterogeneous photocatalysis has been demonstrated by semiconductors such as TiO₂, ZnO, Fe₂O₃, CdS, CuS, and ZnS [2]. TiO₂ is regarded as one of the most effective photocatalysts. The usage of TiO₂ for the degradation of hazardous organic dyes in wastewater has significant potential. The separation of the photocatalyst from the reaction medium remains a significant challenge in photocatalytic applications. In particular, the recovery of TiO₂ after the degradation of organic dyes poses a considerable difficulty, as its fine particulate nature hampers efficient separation from the treated solution. One of the strategies in this regard is the immobilization of the photocatalyst by embedding it into a polymer matrix. This approach facilitates easier separation of the photocatalyst from the reaction medium [3]. Chitosan, a natural biopolymer widely used for its biodegradability and biocompatibility, is an attractive candidate for hydrogel development due to its functional groups that serve as cross-linking sites during hydrogel formation. It has also been combined with photocatalysts and utilized in numerous studies [4-6]. In this study, green-synthesized TiO₂-embedded chitosan films (Bio-TiO₂-CS films) prepared using aloe vera leaf extract offer the advantage of facile separation after the degradation process, as well as potential reusability following dye removal. As the goal of the study, it is believed that the obtained chitosan film hydrogels can be used as an effective bio-template material to disperse TiO2 nanostructures due to their three-dimensional porous structure and appropriate nanopore size distribution, and this feature has led us to investigate the simpler, recyclable, green approach, and biomaterial development of the use of Bio-TiO₂-CS Hydrogel Films in photocatalytic dye removal from water.
FeSbO4 nanomalzeme destekli katı faz mikroekstraksiyonu kullanarak nikel tayini için duyarlı bir analitik yöntemin geliştirilmesi
(Yıldız Technical University Publishing, 2025) Büyük, Muhammed Ali; Serbest, Hakan; Bakırdere, Sezgin
Bu çalışmada, alevli atomik absorpsiyon spektrometresine entegre edilen katı faz mikroekstraksiyon yöntemiyle nikel (Ni) elementinin ön deriştirilmesi amaçlanmıştır. Katı faz adsorbanı olarak FeSbO₄ kimyasal bileşimine sahip, doğal bir mineral yapı olan tripuhit tercih edilmiştir. Laboratuvar ortamında sentetik olarak elde edilen bu nanoyapılar, sırasıyla ultra saf su ve kekik çayı örnekleri içerisindeki nikel iyonlarını yüzeylerine adsorplayarak ekstraksiyon işlemi için kullanılmıştır.
Aloe vera-derived Ag-doped TiO2 nanoparticles immobilized by chitosan films for photo(electro)catalytic and antimicrobial functions
(Elsevier, 2025) Kaba, İbrahim; Bozkurt, Rabia Nur; Altıner Kurt, Eda; Kerkez Kuyumcu, Özge; Koca, Atıf
In this study, as an environmentally friendly and sustainable approach, TiO2 nanoparticles (TiO2 NPs) were prepared by green synthesis method using deep eutectic solvent (DES, ChCl/glycerol (1:2)) based Aloe vera leaves extract obtained by Soxhlet extraction. The DES system functioned concurrently as a green solvent and a functional medium, while the bioactive chemicals in the Aloe vera leaves extract operated as natural reducing and stabilizing agents. The produced TiO2 NPs were doped with silver (Ag) at molar ratios of 0.25, 0.50, and 0.75, and immobilized on a chitosan matrix (Ag/TiO2-CS) to facilitate recovery from the reaction media. The materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), photoluminescence (PL) spectroscopy, scanning electron microscopy-energy dispersive X ray analysis (SEM-EDX) and X-ray photoelectron spectroscopy (XPS). Characterization validated the TiO2 phase, effective Ag incorporation, diminished band gap energy (from 3.34 eV to 2.83 eV), and uniform nanoparticle distribution. PL measurements confirmed that Ag doping reduces carrier charge recombination. The 0.50Ag/ TiO2-CS film displayed the best photocatalytic degradation efficiency for malachite green (93.3 %) under solar irradiation and exhibited a higher photocurrent response relative to undoped TiO2. Moreover, antimicrobial assays demonstrated that 0.50 and 0.75 Ag/TiO2 NPs exhibited significant suppression of S. aureus and E. coli, with low minimum inhibitory concentrations (MIC) (0.40–0.20 µg/mL) and minimum bactericidal concentra tions (MBC), signifying robust bactericidal efficacy. The findings indicate that DES-assisted Aloe vera-mediated synthesis provides an economical and scalable method for producing multifunctional nanocomposites with considerable potential in environmental remediation and biomedical fields.
Phase-selective synthesis of nanoshell hollow V2O3 and V3O5 microspheres as high-performance cathodes for aqueous Zn-ion batteries
(Elsevier, 2025) Aydın Şahin, Selay; Aydoğdu, Büşra; Yaman Uzunoğlu, Gülşah; Yüksel, Recep
Divanadium trioxide (V2O3) microspheres having nano-sized shells were produced by a facile and cost-efficient solvothermal method. Thermal treatment of V2O3 yielded trivanadium pentoxide (V3O5) microspheres. After the synthesis, the structural and electrochemical characterizations were performed in detail. Cathodes produced with the V2O3 and V3O5 materials reached specific capacities of 388 and 320 mAh g− 1 , respectively, at a current density of 0.1 A g− 1 . Aqueous zinc-ion batteries (ZIBs) fabricated with V2O3 and V3O5 cathodes demonstrated high-rate capability and capacity retention. The V2O3 microspheres, which possess a rhombohedral corundum type structure, showed outstanding rate capability (412 mAh g− 1 at 0.1 A g− 1 ; 149 mAh g− 1 at 20 A g− 1 ) and notable cycling stability (95.6 % capacity retention after 1200 cycles at 2 A g− 1 ; 80 % retention at the 2400th cycle at 5 A g− 1 ). Conversely, monoclinic V3O5 provided a comparable initial capacity (374 mAh g− 1 at 0.1 A g− 1 ) but faced rapid capacity decline at high current (26 % retention after 6000 cycles at 5 A g− 1 ). These results emphasize the significance of crystal structure in achieving stable and high-rate Zn2+ storage. In summary, the rhombohedral V2O3 phase exhibits superior Zn2+ transport kinetics and mechanical strength compared to the monoclinic V3O5, which accounts for the differences observed in their electrochemical performance.
Lowered phase transition temperature of VO2(m) via molybdenum doping toward efficient aqueous zinc-ion batteries
(Wiley, 2025) Aydın Şahin, Selay; Aydoğdu, Büşra; Yaman Uzunoğlu, Gülşah; Yüksel, Recep
Rechargeable aqueous zinc-ion batteries have attracted considerable attention as large-scale energy storage systems owing to their safety, sustainability, and cost-effectiveness. However, their practical application has been hindered by limited energy density, primarily determined by cathode performance. Among transition metal oxides, vanadium dioxide (VO2) is particularly appealing due to its layered structure, rich polymorphism, and ability to host Zn2+ ions reversibly. The thermally driven transition from insulating VO2(M) to conductive VO2(R) enhances charge transport through the metal–insulator transition (MIT). In this work, molybdenum doping is employed to lower the MIT temperature of VO2(M). Doping reduces the MIT temperature of the VO2(M) phase to 56.7 °C, resulting in the VO2(R) phase. Electrochemical measurements reveal that Mo-VO2(R) cathodes deliver up to ten times higher capacity than the pristine VO2(M), with 3Mo-VO2(R) reaching 404.8 mAh g–1 at 0.1 A g–1. These findings demonstrate that Mo doping serves as a practical approach to modify VO2(M) and decrease the MIT temperature, while improving electrochemical performance. Moreover, the heteroatom doping strategy suggests a promising pathway for developing other VO2 cathodes for efficient rechargeable batteries, which can leverage the heat dissipated in energy storage systems.
Chia seeds-based gel electrolyte for sustainable and stable zinc ion batteries
(ESC-IS, 2025) Yaman Uzunoğlu, Gülşah
Aqueous zinc batteries represent a promising option for energy storage and conversion technologies in the "post-lithium" era, owing to their elevated energy density, enhanced safety, and affordability. Rechargeable aqueous zinc ion batteries (RZBs) are recognized as promising alternatives to lithium-ion batteries due to their cost-effectiveness, safe-and-sustainable by-design, and scalability. Nonetheless, their performance is hindered by inadequate cyclability, which is attributed to dendrite formation and the hydrogen evolution reaction (HER) occurring at the zinc anode [1].
Synthesis and supramolecular architectures of novel hydrazine derivative homometallic schiff base complexes and their spectroscopic and thermal chacterization
(Springer Nature Link, 2025) Temizkan Özdamar, Kevser
In this study, a hydrazine-containing Schiff base (ScB) and its metal complexes with five different metals—Co (ScB Co), Cu (ScB-Cu), Pb (ScB-Pb), Mn (ScB-Mn), and Zn (ScB-Zn)-were synthesized and subsequently characterized both structurally and thermally. The ScB was synthesized via an elimination reaction between vanillin and phenylhydrazine in ethanol. Hexadentate homometallic complexes (HMCs) were then obtained by reacting the ScB with five different metal salts in tetrahydrofuran. The structural architecture of the synthesized ScB and its HMCs was elucidated using Fourier Transform Infrared (FT-IR) spectroscopy, as well as proton (1 H) and carbon (13C) Nuclear Magnetic Resonance (NMR) spectroscopy. Optical, thermal, and surface characterizations of the structurally confirmed ScB and HMCs were performed using UV-Visible spectroscopy (UV-Vis), thermogravimetric and differential thermogravimetric analyses (TG-DTG), and scanning electron microscopy (SEM), respectively. According to thermogravimetric analysis, the char yield of ScB was 28.2%, while the char yields of its metal complexes—ScB-Co, ScB-Cu, ScB-Pb, ScB-Zn, and ScB-Mn—were 5.4%, 27%, 16%, 19%, and 7.1%, respectively. These results indicate that the incorporation of metal ions into the structure reduced its thermal stability, as evidenced by the decreased residue amounts at 1000 °C.
Aloe vera ve ayva çekirdeği müsilajı içeren aljinat türevli biyobozunur filmlerin üretimi ve karakterizasyonu
(Çanakkale Onsekiz Mart Üniversitesi, 2025) Keke, Zeynep Serra; Temizkan Özdamar, Kevser
Bu çalışma, biyobozunur ve fonksiyonel film üretimi amacıyla ayva çekirdeği musilajı ve aloe vera jeli içeren sodyum aljinat bazlı biyopolimer filmlerin sentezini ve karakterizasyonunu kapsamaktadır. Ayva çekirdeği, yüksek viskozite sağlayan doğal polisakkarit içeriği ile film matrisine mukavemet kazandırırken, aloe vera jeli antimikrobiyal ve antioksidan özellikleriyle biyolojik aktiviteyi güçlendirmektedir [1, 2]. Sodyum aljinat, biyouyumluluk ve film oluşturma kabiliyeti yüksek bir hidrojel olması nedeniyle temel taşıyıcı polimer olarak seçilmiştir [3]. Bu çalışma kapsamında, dört farklı hidrojel film formülasyonu hazırlanmıştır. Her bir formülasyon, sodyum aljinat, aloe vera, ayva çekirdeği, selüloz hidroksi etil selüloz (HEC) ve gliserol bileşenlerinin belirli oranlarda karıştırılmasıyla oluşturulmuştur. Film yapısında bulunan bileşenlerin birbirleriyle olan kimyasal ve fiziksel etkileşimleri, malzemenin mekanik ve fonksiyonel özelliklerini belirlemektedir. Film üretiminde solvent dökme yöntemi uygulanmış ve karakterizasyon aşamasında mekanik dayanım, su buharı geçirgenliği, biyobozunurluk ve antibakteriyel aktivite parametreleri değerlendirilmiştir. Fourier Dönüşümlü Kızılötesi Spektroskopisi (FTIR), UV-Vis Spektroskopisi ve Termogravimetrik Analiz (TGA) ile kimyasal yapı ve termal stabilite analizleri gerçekleştirilmiştir. Biyobozunurluk testleri, filmlerin çevresel koşullarda zamanla parçalanabilir olduğunu gösterirken, antibakteriyel testler inhibisyon etkisini doğrulamıştır. Elde edilen sonuçlar, ayva çekirdeği ve aloe vera içeren biyopolimer filmlerin sürdürülebilir ve çevre dostu bir alternatif sunduğunu göstermektedir. Bu bulgular, organik çözücü ve yüksek sıcaklık kullanmaksızın, biyobozunur malzemeler üzerine yapılan araştırmalara katkı sağlaması hedeflenmektedir.
Investigation of photocatalytic degradation of methyl orange using zinc oxide-supported chitosan hydrogel beads
(Taylor & Francis, 2025) Kaba, İbrahim; Bozkurt, Rabia Nur; Kılıç, Behris
In this study, chitosan-based ZnO supported hydrogels (CZ–H) were synthesized to evaluatetheir photocatalytic degradation performance against methyl orange (MO) dye. The compos-ite hydrogels were characterized using X-ray Diffraction (XRD), UV–Vis DRS, ScanningElectron Microscopy (SEM-EDS), Thermogravimetric Analysis (TGA), and Fourier TransformInfrared Spectroscopy (FTIR). These characterization results confirmed the successful forma-tion of the CZ–H composite structure. The band gap of the composite was approximately2.77 eV, supporting enhanced photocatalytic activity. Photocatalytic experiments showedthat CZ–H removed 74% of MO within 60 min, compared to 42% for pure chitosan beads,with reaction rate constants of 0.0237 min−1 and 0.0113 min−1, respectively. Moreover, theCZ–H beads demonstrated good reusability with minimal loss in efficiency over multiplecycles. These findings highlight the potential of CZ–H as a stable, effective, and reusablephotocatalyst for the efficient removal of dyes from wastewater.
Improving physiological solubility and gene transfer efficiency of chitosan via 3-nitrobenzaldehyde and amino acid conjugation
(Elsevier, 2025) Bal, Kevser; Kaplan, Özlem; Şentürk, Sema; Küçükertuğrul Çelik, Sibel; Demir, Kamber; Gök, Mehmet Koray
In this study, chitosan was chemically modified with 3-nitrobenzaldehyde (3NBA) and three amino acids (arginine, cysteine, and histidine) to enhance its gene delivery performance. 3-NBA was selected for its known DNA binding properties, while the amino acids were chosen based on their functional groups, which can improve solubility, facilitate cellular uptake, and contribute to endosomal escape. The modified chitosan polymers were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance Spectroscopy (NMR). Nanoparticles were prepared using the ionotropic gelation method, and their particle size, polydispersity index (PDI), zeta potential were analyzed by dynamic light scattering (DLS). The particle sizes ranged from 105.07 ± 3.45 to 206.15 ± 10.39 nm, with PDI values between 0.29 ± 0.01 and 0.39 ± 0.02. Zeta potentials were measured between 32.05 ± 0.49 mV and 51.95 ± 0.35 mV. The cysteine-modified chitosan (Chi-3NBACys) exhibited approximately 8.4-fold higher solubility than unmodified chitosan. In vitro studies demonstrated that the modified chitosan nanoparticles exhibited low cytotoxicity in HEK293T cells. Among the tested formulations, Chi-3NBACys showed the highest transfection efficiency, comparable to commercial agent Lipofectamine™ 2000. These findings suggest that chitosan nanoparticles modified with 3-NBA and amino acids can be safe and efficient non-viral gene delivery vectors.

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