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https://hdl.handle.net/20.500.12428/2237

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In Vivo Wound Healing and Immune Response Studies of Chitosan Cryogels With Invertebrate Model Organism Galleria mellonella
(Wiley, 2025) Ekici, Sema; Kaya, Serhat; Durucu, Gürkan
In the present study, it was aimed to prepare single and double network chitosan (Ch) cryogels cross-linked with glutaraldehyde (G), which can be recommended for use as model wound dressings and hemostatic agents, and to reveal in vivo studies with Galleria mellonella. An in vivo study about Ch cryogels with these larvae was not declared in the literature, so our study is the first of its kind. G. mellonella was used to determine the effects of cryogels on immunity, oxidative stress, and wound healing. Cinnamic acid (CA) was loaded onto the cryogels, and the percent cumulative release data of CA were found to be in the range of 69%-80%. The results show that loading of CA onto [Ch-3]cry cryogels considerably improved immune responses; the [Ch-3]cry-CA group was the most successful in terms of immunological response, oxidative stress balance, and wound healing. In accordance with the 3R principles of ethical animal research, the use of G. mellonella in this study served as a scientifically relevant and ethically responsible alternative model to mammals for preliminary assessment of wound healing potential and innate immune activation. The porous structures, high mechanical strengths, and rapidly swelling-deswelling abilities of [Ch-2@Ch]cry and [Ch-3]cry cryogels indicated that these may be suitable for biomedical applications. Analysis of SEM micrographs indicated that the morphology of dual network cryogels prepared in the form of interpenetrating polymeric networks (IPNs) was more regular and homodispersed with respect to single network cryogels. The compressive elasticity modulus (E) values of IPNs cryogels (0.160 N/mm) is approximately 4.6 times that of Ch cryogels with a single network (0.035 N/mm).
Transformation of Cytotoxic Linear Polyethyleneimine (L-PEI) Into Biocompatible and Hemacompatible Crosslinked Particles With Antimicrobial Properties
(Wiley, 2025) Demirci, Şahin; Sağbaş Suner, Selin; Şahiner, Mehtap; Güven, Olgun; Şahiner, Nurettin
Linear polyethyleneimine (L-PEI) microgel/particles were prepared using glycerol diglycidyl ether (GDE) as crosslinker at various mole ratios, 10%, 25%, and 50% of L-PEI repeating unit, and designated as L-PEI-1, L-PEI-2, and L-PEI-3, respectively. All microgels were found blood compatible with < 2% hemolysis and > 80% blood clotting indexes at 1000 μg/mL concentrations, whereas L-PEI is hemolytic (> 80% hemolysis). Similarly, L-PEI showed cytotoxicity on L929 fibroblasts even at 50 μg/mL, while > 80% cell viability was observed for L-PEI-based particles even at 1000 μg/mL. Although it is regarded as less cytotoxic than branched PEI, the cross-linked L-PEI particles effectively circumvent cytotoxicity as the most important limitation of L-PEI in biological applications. Additionally, the higher antimicrobial activity against Escherichia coli, gram-negative bacteria, Bacillus subtilis, gram-positive bacteria strains, and Candida albicans, yeast strains was observed for L-PEI-1 and protonated L-PEI-1 particles. Moreover, the antibacterial activity of L-PEI-1 particles was further improved after the inclusion of Ag(I) and Cu(II) ions within L-PEI particles as Ag@L-PEI-1 and Cu@L-PEI-1 composites, respectively. The lower MIC and MBC values were determined for Ag@L-PEI-1 particles against Escherichia coli and Bacillus subtilis as 0.079 and 0.312 mg/mL, respectively, and an MFC value for Candida albicans was 0.156 mg/mL for Ag@L-PEI-1 particles.
Development of Stable Microemulsions Containing Laurel Essential Oil Using Amylopectin and Gum Arabic as Natural Emulsifiers
(Wiley, 2025) Berber, Mehmet Mert; Çelebi Uzkuç, Nesrin Merve; Uzkuç, Hasan; Tarhan Kuzu, Kübra; İşleten Hoşoğlu, Müge; Özmen Togay, Sine; Kırca Toklucu, Aysegül; Karagül Yüceer, Yonca; Kurt, Saliha B.; Şahiner, Nurettin
This study aimed to develop food-grade microemulsions of laurel essential oil (L-EO) (MEs) stabilized with amylopectin (L-AP) and gum arabic (L-GA) and to determine characteristic properties of the MEs at different pH and temperatures during storage. L-EO was extracted using the microwave-assisted hydrodistillation technique. The prepared ME droplets ranged in size range from 328 to 347 nm in L-AP (pH 6.0) and from 327 to 432 nm in L-GA (pH 3.0). The total phenolic content and antioxidant capacity were 170.60 mg/L gallic acid equivalent (GAE) and 0.93 mM Trolox/mL in L-AP, respectively, while total phenolic content was 243.10 mg/L GAE and antioxidant capacity was 1.19 mM Trolox/mL in L-GA. Additionally, the MEs demonstrated relatively potent antimicrobial activity against Escherichia coli, Bacillus cereus, and Staphylococcus aureus strains. The main volatile compounds of L-EO were identified as 1,8-cineole (33.4%), sabinene (8.4%), and linalool L (6.6%).
Chitosan-Based Cryogels for Esterase Immobilization
(Wiley-V C H Verlag Gmbh, 2025) Ekici, Sema; Baybaş, Demet; Ayan, Beyza
Preparing chitosan (Ch) cryogels in the form of full-interpenetrating polymer networks (IPNs) is an advantageous approach since the IPN cryogels have a more regular and tight pore distribution and durable spongy structure, including enhanced mechanical properties and more functional groups. In the present research, Ch–Ch ([Ch]cry) and Ch-pAAm (polyacrylamide) full-IPN cryogels ([Ch-pAAm]cry) were synthesized, characterized, and then used for the immobilization of enzyme (porcine/pig liver esterase (PLE)) using the adsorption method. The results of mechanical analysis have shown that the compression elasticity modulus (E) value of [Ch-pAAm]cry full-IPN cryogel is 47 times that of [Ch]cry. The introduction of pAAm within full-IPN cryogels increases the compression strength; however, it decreases their ability for esterase immobilization and swelling degrees (Se). The esterase adsorption capacity (XL) values are 90.7 and 13.4 mg g−1 for [Ch]cry and [Ch-pAAm]cry, respectively. Adsorption equilibrium time of [Ch]cry is shorter (360 min) than [Ch-pAAm]cry (600 min). According to Km values, the order of affinity for the 4-nitrophenyl acetate (pNPA) substrate is [Ch-pAAm]cry (6.9 mM) > [Ch]cry (22.1 mM) > free enzyme (60.4 mM). The porosity parameter, Vp (cm3 pore (g dry cryogel)−1, was calculated to be 36.18 ± 4.77 for [Ch]cry and 5.00 ± 0.76 for [Ch-pAAm]cry, indicating that [Ch]cry had larger pores than [Ch-pAAm]cry.
Design and thermal profiling of ethyl carbazole-based poly(phenoxy-imine)s: synthesis and characterization
(Springer, 2025) Kaya, İsmet; Yılmaz, Mehmet Hakan; Kolcu, Feyza
A series of Schiff base monomers were synthesized via the condensation of 3-amino-9-ethylcarbazole with various aldehydes, including 3-hydroxybenzaldehyde (3-HBA), 4-hydroxybenzaldehyde (4-HBA), 2-hydroxy-1-naphthaldehyde (2-HNA), and ortho-vanillin. These monomers were subsequently polymerized through oxidative polycondensation using NaOCl as the oxidant to yield corresponding poly(phenoxy-imine)s, namely Poly(3ECIMP), Poly(4ECIMP), Poly(ECIMN), and Poly(ECIMMP). The chemical structures of the synthesized compounds were confirmed using FTIR, UV–Vis, and both 1H and 13C NMR spectroscopy. Thermal characterization using TG–DTA and DSC demonstrated that the synthesized polymers possess excellent thermal stability, as evidenced by their glass transition temperatures between 145 and 161 °C and char yields reaching up to 38.22% at 1000 °C. Furthermore, limiting oxygen index values exceeding 28% indicate that these materials exhibit self-extinguishing behavior. Photoluminescence studies conducted in DMF demonstrated intense fluorescence, particularly for Poly(ECIMN), which exhibited yellow–orange emission upon excitation at 502 nm due to the presence of naphthalene moieties that enhance π-electron delocalization. Optical and electrochemical band gap analyses indicated significantly reduced Eg values for the polymers compared to their monomers, with Poly(ECIMN) showing the lowest band gap of 2.39 eV. Cyclic voltammetry results aligned with optical measurements, confirming improved charge-transfer characteristics in the conjugated polymer backbone. Surface morphology assessed by FE-SEM revealed porous structures, suggesting applicability in gas adsorption or catalytic systems. Size exclusion chromatography confirmed the formation of high molecular weight polymers with narrow polydispersity indices. Collectively, the unique combination of thermal durability, photophysical responsiveness, and structural robustness highlights the potential of these ethyl carbazole-based poly(phenoxy-imine)s in applications spanning optoelectronics, thermal protection, and fluorescence-based sensing.
A Comparative Study of Nitrogen Doped Carbon Dots Prepared from Linear Polyethyleneimine (L-PEI) and Branched Polyethyleneimine (B-PEI): Thermal, Optical, Biocompatibility, Sensor, Antibacterial, and Light-Induced Antibacterial Activity
(Springer/Plenum Publishers, 2025) Demirci, Şahin; Sağbaş Suner, Selin; Şahiner, Mehtap; Akçalı, Alper; Güven, Olgun; Şahiner, Nurettin
The N-doped carbon dots (CDs) prepared in the presence of citric acid (CA) as carbon source, using linear poly(ethylene imine) (L-PEI) and branched poly(ethylene imine) (B-PEI) as nitrogen doping agents were prepared via hydrothermal/solvothermal technique at 250 degrees C in a Teflon-lined autoclave. The zeta potentials of L-PEI CDs and B-PEI CDs were determined as + 9.8 +/- 4 and 0.1 +/- 0.5 mV with 47 +/- 3 and 54 +/- 5 nm sizes, respectively. Bandgap values for L-PEI CDs and B-PEI CDs were estimated as 3.06 and 3.37 eV, respectively. The fluorescence intensities of L-PEI CDs and B-PEI CDs were measured as 59,310(a.u.), and 46,370(a.u.) at 474 and 442 nm, respectively, under 400 and 320 nm excitation wavelengths and 700 V PMT voltage. A higher quantum yield% value was observed for L-PEI CDs with 37 +/- 2.9%. Both L-PEI CDs and B-PEI CDs were found biocompatible up to 1000 mu g/mL concentration with > 80% L929 fibroblast cell viability. The limit of detection (LOD) values for Fe3+ by L-PEI CDs and B-PEI CDs were determined as 0.58 and 2.14 mg/mL, respectively. Both L-PEI CDs and B-PEI CDs at 10 mg/mL concentration resulted in 50% bacterial killing for gram-negative E. coli, gram-positive B. subtilis, and yeast C. albicans microorganisms. Also, the light activation of L-PEI CDs and B-PEI CDs induces almost 70 and 40% bacterial killing for gram-positive B. subtilis in 30 min. Moreover, they have a limit of detection (LOD) value of 0.58 mg/mL for Fe3+ ions, in addition to exhibiting biocompatibility and antibacterial properties.
Investigation of gas sensing properties of organic π–π* complexes spin coated thin films in dry and humid environment
(Springer, 2025) Şen, Sibel; Özbek, Zikriye; Aydın, Fatma; Capan, R.
Exposure to gaseous pollutants in both enclosed and open environments poses a significant risk to human health. In this study, an optical detection-based sensor was developed for the selective detection of toxic ammonia gas in the environment at low concentrations. Three newly synthesized organic π–π* charge-transfer (CT) complexes—anthracene picrate (ANTPc), phenanthrene picrate (PHENPc), and pyrene picrate (PYRPc)—obtained from polynuclear aromatic hydrocarbons and picric acid precursors (ANTP, PHENP, and PYRP, respectively), were evaluated for the first time as sensing thin film materials in gas sensor applications. These complexes were transferred as thin films onto the substrates using the spin-coating method for structural characterization and investigation of their sensor properties. The sensor analyses were conducted using the surface plasmon resonance (SPR) method. It was observed that the PHENPc-, ANTPc-, and PRYPc-based thin film sensors were highly selective to ammonia with the sensitivity values of 0.00007, 0.0003, and 0.0017 ppm−1, respectively. Although they are very similar to each other in terms of chemical structure, the thin film sensors produced from these three materials exhibited different responses to the vapors at room temperature. In the last section of the study, repeated gas detection measurements conducted under varying humidity conditions demonstrated that humidity affects the sensitivity of the sensors.
A Novel ruthenium(II) complex-based electrode for non-enzymatic glucose sensing applications
(Springer, 2025) Küçükoflaz Korkmaz, Merve; Dayan, Serkan; Özdemir, Namık; Erdener, Diğdem; Dayan, Osman; Çetinkaya, Bekir
Ruthenium-based complexes demonstrate high potential in the catalysation of the electrochemical oxidation of glucose, offering high sensitivity and stability in glucose detection. In this study, a ruthenium complex (Ru1) was synthesised using 2,2′-bipyridine-4,4′-dicarboxylic acid (DCBpy), potassium iodide (KI) and [RuCl₂(p-cymene)]₂. The structural properties of Ru1 were investigated using X-ray diffraction (XRD), nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and UV–vis spectroscopy analyses, which revealed its structure. The electrochemical behaviour of the Ru1 complex was systematically investigated and found to be promising for application in a glucose biosensor. Cyclic voltammetry measurements revealed an increase in electrochemical activity on the electrode surface over time, showing a steady rise at a potential of 0.32 V. This indicates high sensitivity and reliability in glucose detection. Chronoamperometric analysis showed a linear response to glucose concentrations ranging from 0.1 to 0.8 mM, demonstrating the sensor's sensitivity. These properties make the Ru1 complex a promising candidate for use in glucose detection biosensors. In conclusion, the complex's electrocatalytic activity and stability could be key to advancing biosensor technologies by enhancing sensitivity.
High thermal stability and dielectric performance of phenylhydrazine-based Schiff base oligomers obtained via oxidative polycondensation
(Springer, 2025) Solmaz, Adnan; Kaya, İsmet; Bayır, Erdal
In this study, the 2-PHMBD Schiff base, synthesized through the condensation of 2,4-dihydroxybenzaldehyde (2,4-DHBA) with phenylhydrazine (PH), was subjected to oxidative polymerization in a basic medium using hydrogen peroxide (H2O2), sodium hypochlorite (NaOCl), and molecular oxygen (O2) as oxidizing agents. Three oligomers, designated as o-(2-PHMBD)-P, o-(2-PHMBD)-H, and o-(2-PHMBD)-O, were successfully obtained and comprehensively characterized by FT-IR, 1H-13C-NMR, UV-Vis, CV, GPC, SEM, TGA, and DSC analyses. Spectroscopic results confirmed the successful polymerization, while morphological and thermal analyses revealed the distinct physical characteristics of the oligomers. According to GPC data, o-(2-PHMBD)-H exhibited the highest average molecular weight of 4700 Da, and TGA analysis demonstrated that o-(2-PHMBD)-O had the highest thermal stability with a residue of 46% at 1000 degrees C. The DSC results showed the highest glass transition temperature of 132 degrees C for o-(2-PHMBD)-H. UV-Vis and CV measurements indicated reduced optical and electrochemical band gaps compared with the monomer, with the lowest optical band gap determined as 2.74 eV. Dielectric measurements revealed that o-(2-PHMBD)-H displayed the highest dielectric constant of 2.57 and conductivity of 2.49 x 10(-)7 S cm(-)1. These results demonstrate that phenylhydrazine-based Schiff base oligomers possess high thermal stability and favorable dielectric properties, making them promising materials for optoelectronic and dielectric device applications.
Single, Double, and Multiple-Heteroatoms Doped Carbon Quantum Dots as Effective Light-Induced Antimicrobial Materials
(Springer/Plenum Publishers, 2025) Sağbaş Suner, Selin; Şahiner, Mehtap; Demirci, Şahin; Şahiner, Nurettin
Single-, dual-, and multi-heteroatoms such as N, S, and B-doped carbon quantum dots (CQ-dots) were prepared to determine their dopant effects on anti-pathogenic activities. The CQ-dots were prepared using maleic acid (MA), poly(vinyl amine) (PVAm), cysteine (Cys), and boric acid (BA) as carbon, nitrogen, sulfur, and boron sources, respectively. In 345–415 nm emission wavelength range, 45.9 ± 2.4% quantum yield for dual heteroatom-doped (N/B-doped) CQ-dots were attained. Antimicrobial studies revealed that N-doped CQ-dots have significant antimicrobial susceptibility to both bacteria and fungi. The zeta potential value of N-doped CQDs had -4.9 mV was changed to -9.2 and -11.5 mV upon N/S- and N/B-doping, respectively. N/B-doped CQ-dots afforded the highest antibacterial activity providing a 1.56 mg/mL minimum inhibitory concentration (MIC) value against Escherichia coli, whereas N/S-doped CQ-dots had the highest antimicrobial activity against Staphylococcus aureus and Candida albicans yeast, 0.37 mg/mL MIC values. The photodynamic antimicrobial studies of N-, N/S-, N/B-, and N/S/B-doped CQ-dots significantly eradicated the bacteria and fungus colony upon UV-A light exposure for 30 min, with > 50% microbial colonial inhibitions. Both N and N/S-doped CQ-dots exhibit higher biofilm eradication/inhibition efficacy on Candida albicans biofilm, and all CQ-dots are biocompatible according to blood compatibility and cytotoxicity analysis at 1000 μg/mL.
Design, synthesis, characterization, computational analysis, structure-activity relationship, and investigation of the anticancer potential of novel dibromodibenzoazepine-based hybrid structures
(Springer, 2025) Allito, Azza; Önder, Alper; Cömert Önder, Ferah; Erdoğan, Musa
In this study, ten novel dibromodibenzoazepine-substituted triazole hybrid compounds (AZ1-AZ10) were designed via a molecular hybridization approach and synthesized using click chemistry methodology. In the synthesis, the dibromodibenzoazepine derivative (12) was initially synthesized via bromination. Subsequent propargylation yielded the key intermediate, dibromodibenzoazepine-propargyl derivative (13). The Cu (I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction of propargyl derivative (13) with various substituted azide derivatives afforded the target hybrid compounds in high yields. The structures of these compounds were characterized using various spectroscopic techniques, including H-1 NMR, C-13 NMR, and MS. Among the synthesized compounds, AZ9 was determined to have the highest cytotoxicity on breast and colon cancer cell lines, including BT20, MCF7, MDA-MB-231, and HT29 with the IC50 values of 0.54 +/- 0.09 mu M, 1.83 +/- 0.87 mu M, 3.88 +/- 0.15 mu M, and 5.31 +/- 0.38 mu M, respectively. In addition, AZ8 showed the cytotoxicity on BT20 and HT29 cells below 10 mu M. The cytotoxicity of AZ10 in studied cancer cell lines was calculated below 20 mu M. The compounds were investigated by computational analysis including molecular docking, molecular dynamics (MD) simulations, Molecular Mechanics with Generalized Born and Surface Area Solvation (MM/GBSA), and ADME predictions. As a result, AZ8-AZ10 may be promising anticancer agents targeting SphK1 and CDK6 to provide new perspectives for the design and development of novel click products.
Impact of Kernel Opacity on Protein Content, Some Essential Amino Acids, and Zein Film Properties in Maize
(Springer, 2025) Gümüş, Muhammet; Danışman, Merve; Kibar, Kübra; Yakar, Emin; Oral, Ayhan; Kahrıman, Fatih
Opacity is one of the key indicators of protein quality in maize. Compared to normal maize genotypes, opaque maize contains higher amounts of essential amino acids, contributing to higher levels of lysine and tryptophan, which are limiting in maize diets. These essential amino acids are particularly critical for zeins, the dominant protein fraction in maize, as zeins serve as valuable raw materials with both industrial and nutritional applications. Although zein-based films have been widely studied, there is limited research comparing the properties of zein films derived from maize samples with different kernel opacity levels. In this study, a maize genotype known to possess the opaque trait was used to obtain samples with five different opacity levels. Protein, lysine, and tryptophan content variations were analyzed in flour, raw zein, and zein film samples. Additionally, the dynamic mechanical analysis (DMA) of zein films was performed according to opacity levels. The data obtained were statistically evaluated using one-way analysis of variance (ANOVA), and differences between means were compared using the least significant difference (LSD) test (P < 0.05). The protein content was found to range between 7.6 and 10.14% in flour and 80.6-86.9% in raw zein. Lysine content varied between 1.00 and 1.81% in flour and 0.03-2.28% in raw zein, while tryptophan content ranged from 0.175 to 0.228% in flour to 0.38-2.17% in raw zein. An increase in opacity level led to a decrease in protein content; however, it significantly enhanced the essential amino acid content across all sample types. Furthermore, opacity levels had a substantial impact on the structural properties of zein films. Significant differences were observed among the film samples in terms of color intensity (e.g., L* values ranging from 83.64 in PVA-PEG control to 68.34 in PVA-PEG-Zein100), chroma (2.64 to 40.45), and hue angle (23.30 degrees to 92.43 degrees). Additionally, film thickness varied significantly between 0.028 mm and 0.195 mm across formulations. Mechanical differences were also evident, particularly in storage modulus and flexibility, as quantified through dynamic mechanical analysis (DMA). Although variations in glass transition temperature were modest and appeared to correlate with differences in film opacity-attributable to the lysine-to-tryptophan ratio-a pronounced enhancement in storage modulus was observed. Notably, the formulation exhibiting the highest lysine-tryptophan content showed an increase of up to 1000 times in the storage modulus.The findings suggest that processing and utilizing maize samples separated by opacity level for raw material production could provide important nutritional advantages for food and other applications.
Boron Containing Curcumin-Like Compound as an Acetylcholinesterase Inhibitor and Anticancer Agent: Synthesis, Biological Evaluation, and Computational Insights
(Humana Press Inc, 2025) Cömert Önder, Ferah; Ural, Kadircan; Önder, Alper; Özpolat, Bülent; Ay, Mehmet
Alzheimer's disease (AD) and cancer are significant global health challenges that highlight the need for the development of new therapeutics. Targeting biological mechanisms involved in both AD and cancer could be an effective treatment strategy for developing novel inhibitors. In this study, we investigated the effect of a newly synthesized boron containing curcumin-like compound as a potential acetylcholinesterase (AChE) inhibitor along with its cytotoxic effects on breast and colorectal cancer cell lines. Compound A exhibited a potent AChE inhibitory activity (IC50 = 22.89 +/- 2.32 nM), demonstrating that it was more effective than the known inhibitors donepezil (IC50 = 28.32 +/- 3.27 nM) and tacrine. Compound A showed a moderate cytotoxic activity on MCF-7 and BT20 cells with the IC50 values 40.70 +/- 2.31 mu M and 41.71 +/- 4.51 mu M, respectively. Throughout molecular dynamics (MD) simulations, the RMSD value of the protein was calculated as 1.56 +/- 0.20 & Aring; and 1.65 +/- 0.19 & Aring; for the complexes of compound A and curcumin, respectively. The interactions with specific amino acid residues such as Tyr124, Tyr337, and Trp86 for AChE, and Trp82, His438, and Tyr332 for BChE were obtained. Additionally, MM/GBSA calculations demonstrated that Compound A had the highest binding free energies (-88.89 +/- 8.34 kcal/mol for AChE and -73.25 +/- 8.83 kcal/mol for BChE) compared to curcumin (-67.87 +/- 5.48 kcal/mol for AChE and -51.68 +/- 5.28 kcal/mol for BChE) and tacrine (-56.67 +/- 2.22 kcal/mol for BChE) were calculated. Overall, these findings suggest that Compound A is a promising agent with its potent AChE inhibitory activity and anticancer potential, making it a valuable candidate for further research in neurodegenerative diseases and cancer therapy.
Comparative Study of Enzymatic and Oxidative Polymerization of a Benzothiazole-Based Schiff Base and Its Antibacterial Properties
(Springer Heidelberg, 2025) Kaya, İsmet; Solmaz, Adnan; Abuawad, Mohammed Majed Shible
In this study, the Schiff base 1-(((6-nitrobenzo[d]thiazol-2-yl) imino)methyl)naphthalen-2-ol (NBTIMN) was synthesized and subsequently polymerized by two different methods. Oxidative polymerization in the presence of organic (o-(NBTIMN)-O) and aqueous alkaline media (o-(NBTIMN)-A) was one of the techniques. The other was enzyme-catalyzed oxidative polymerization (o-(NBTIMN)-E), which was conducted at room temperature with hydrogen peroxide and the enzyme horse radish peroxidase (HRP). The structures of the obtained oligomers were characterized using FT-IR, 1H-13C-NMR, UV–Vis, CV, and GPC analyses, and their electrochemical and optical band gaps were determined as 2.68, 2.66, and 2.49 eV, and 3.08, 2.90, and 3.07 eV for o-(NBTIMN)-O, o-(NBTIMN)-A, and o-(NBTIMN)-E, respectively. Thermal analyses demonstrated that the o-(NBTIMN)-O and o-(NBTIMN)-A derivatives exhibited enhanced thermal stability, characterized by higher decomposition temperatures and LOI values. SEM analyses revealed distinct differences in surface morphologies depending on the polymerization conditions. Antibacterial assays showed that o-(NBTIMN)-O exhibited the strongest broad-spectrum inhibition, whereas NBTIMN displayed pronounced activity against S. aureus. In contrast, o-(NBTIMN)-A and o-(NBTIMN)-E were found to be inactive. These results highlight the critical influence of polymerization conditions on both the physicochemical characteristics and the biological activities of the synthesized structures. Importantly, the comparative design of enzymatic and chemical polymerization demonstrates the potential for environmentally friendly synthesis strategies. The distinct electrochemical and thermal properties suggest applicability in electronics and sensor-related fields, while the pronounced antibacterial activity of o-(NBTIMN)-O holds promise for biomedical and antimicrobial applications.
Gold and silver nanoparticle decorated biocompatible and antibacterial xanthan gum/poly (HEMA-co-APTMACl) hydrogels for wound healing
(Springernature, 2025) Savranoğlu Kulabaş, Seda; Atlı, İlknur; Atalay, Hazal Nazlıcan; Boyuneğmez Tümer, Tuğba; Özay, Hava; Özay, Özgür
A delayed skin wound healing process increases the risk of infection and necessitates implementing effective treatment strategies. From this perspective, biocompatible and antibacterial hydrogels stand out as innovative biomaterials that support wound healing. In this research, a semi-interpenetrating polymer network (s-IPN) strategy was used to improve the mechanical strength, cytocompatibility, and antibacterial properties of natural polysaccharide-based hydrogels. In this context, natural polymer-based XG/poly (HEMA-co-APTMACl) hydrogels were synthesized by redox polymerization reaction. The stability of metal nanoparticles was ensured by utilizing the rich polyphenol and flavonoid components of C. Orientalis. The synthesized hydrogels were in situ functionalized with biosynthesized silver (55 nm) and gold (56 nm) nanoparticles to enhance their biocompatibility and biofunctionality. Their antibacterial activity was assessed against P. aeruginosa, S. aureus, B. cereus, and E. faecalis using the disk diffusion method. Hydrogelfilm@Ag inhibited all tested bacterial strains (7.5–8.8 mm), while Hydrogelfilm@Au exhibited stronger antibacterial activity, particularly against E. faecalis (10.3 mm) and B. cereus (9.7 mm). In contrast, the Hydrogelfilm was only effective against S. aureus (7.7 mm). The hydrogel formulations were tested for cytocompatibility and wound healing potential using HUVECs. All hydrogels composites (Hydrogelfilm@Au, @Ag, and @HF) were non-toxic and exhibited enhanced biocompatibility, promoting significant cell proliferation at all tested concentrations (5–20%). In wound healing assays, Hydrogelfilm@HF achieved complete wound closure within 12 h even at a 5% concentration, demonstrating superior regenerative potential. Overall, hydrogels incorporating green-synthesized silver and gold nanoparticles demonstrated excellent antibacterial and wound-healing properties, highlighting their promise as advanced biomaterials for tissue regeneration applications.
Construction of core@shell NiCo2S4@conductive polythiophene nanocone arrays on carbon cloth for high-performance supercapacitors
(Elsevier, 2025) Budak Doğramacı, Özlem; Zenkin, Kübra; Durmuş, Sefa; Bilici, Ali; Koca, Atıf
In recent years, flexible and portable supercapacitor devices have become a focus of attention in the field of energy storage. However, challenges in the selection and preparation of appropriate electrode materials remain. The hierarchical constructing of conducting polymer@transition metal sulfide composites on the flexible carbon cloth substrate is an effective strategy to achieve high-performance supercapacitors. In here, highly conductive polythiophene (Pth) nanocone arrays are hierarchically constructed on the NiCo2S4 (NCS) coated carbon fiber cloth (CC). The modification of NCS electrode surface with conductive polythiophene (Pth) layer (about 6.21 S/cm) is based on a facile dip-coating process. This facile process allows the formation a conductive polythiophene (Pth) layer on the NCS nanoneedles by protecting porous NCS morphology. Pth shell not only increases the conductivity of NCS electrode but also alleviates agglomeration during charge-discharge process. The synergistic effect between NCS and Pth improves the capacitive characteristics of electrode. Compared to NCS@CC and Pth@CC electrodes, NCS@Pth(0.3)@CC composite electrode exhibits a superior specific capacitance (1632.8 F g−1 at 1 A g−1 of current density) and an outstanding retention stability (90.1 % after 5000 cycles). These impressive results emphasize the potential of the newly developed hybrid structure as a high-performance electrode material for electrochemical devices.
Ethylparaben removal using chitin carbons derived from Hermetia illucens pupa casings
(Elsevier Science Sa, 2025) Bazan-Wozniak, Aleksandra; Nosal-Wiercinska, Agnieszka; Yılmaz, Selehattin; Pietrzak, Robert
The study developed activated carbons with a highly developed specific surface area, showing excellent adsorption properties for aqueous ethylparaben solutions and suitability for reuse. Empty pupal casings of Hermetia illucens served as precursors. Using a two-step process-microwave carbonization and activation with potassium carbonate-carbons with surface areas of 1200-2302 m2/g were produced. The resulting materials featured a highly developed pore structure, combining micropores and mesopores, ideal for adsorbing organic molecules. Adsorption kinetics and isotherms were analyzed using statistical physical models. The activated carbons exhibited a maximum adsorption capacity of 739 mg/g, demonstrating chemisorption behavior aligned with linear and non-linear pseudo-second-order kinetics and the linear Langmuir isotherm. The adsorption mechanism involved it-it interactions, hydrogen bonding, and electrostatic forces between ethylparaben molecules and the adsorbent surface. The process was endothermic and spontaneous under the tested conditions. The carbons retained high reusability, achieving 84 % desorption efficiency after three cycles. This research highlights the potential of waste-derived activated carbons for efficient and sustainable adsorption applications.
Enhanced antimicrobial and anticancer activities of zein protein-agarose@Au composite hydrogel for controlled release of silibinin in colon cancer therapy
(Elsevier, 2025) Atlı, İlknur; Ilgın, Pınar; Karabayır, Elif Sultan; Özay, Hava; Özay, Özgür
In this study, biodegradable hydrogel films based on natural proteins and polysaccharides were synthesized in order to improve controlled drug release, cytocompatibility and antibacterial properties. Biosynthesized gold nanoparticles were incorporated in situ cancer drug-loaded hydrogels to enhance their antibacterial, biocompatible, and cytotoxic characteristics. Then, in order to investigate the association of silibinin drug used in cancer treatment with AuNPs, drug release profile was evaluated under different environmental conditions and release kinetics were analyzed. In addition, antibacterial effects were determined by testing on Gram-negative and Gram-positive bacteria by Disk Diffusion method. As a result, cytocompatibility of silibinin drug and AuNPs in hydrogel networks and their effects on cancer cells were determined by MTT assay using human dermal fibroblasts (CCD1079KSk) and colon cancer (HT-29) cell lines. Thus, AuNPs created a synergistic effect in cancer treatment and strengthened the effect of Silibinin on tumor cells. In addition, it was determined that it exhibited a biocompatible structure by showing minimal toxicity to healthy human skin cells. This innovative drug delivery system has the potential to offer a biomaterial-based alternative in both cancer treatment and wound dressing material with its controlled release feature.
Hydrogen generation from the hydrolysis of piperazine bisborane as new hydrogen carrier material catalyzed by Ru0 nanoparticles embedded in agarose biofilms
(Pergamon-Elsevier Science Ltd, 2025) Özay, Hava; Ilgın, Pınar; Atlı, İlknur; Özay, Özgür
In this study, firstly, piperazine bisborane (PBB) was synthesized and characterized as a solid hydrogen carrier material. Subsequently, a new catalytic system, agarose hydrogel@Ru (AGH@Ru), in which nanosized Ru0 particles were homogeneously dispersed and used as a catalyst for hydrogen production from the hydrolysis of PBB, was prepared. After the structural and morphological characterization of the catalyst, for the first time in the literature, catalytic hydrogen production from the hydrolysis of PBB was initiated. As a result of catalytic hydrolysis reactions conducted under different reaction conditions, it was determined that AGH@Ru achieved 100 % efficiency in the hydrolysis reaction and produced 6 mol of hydrogen per mole of PBB. The activation parameters for the hydrolysis reaction of PBB catalyzed by AGH@Ru were calculated as Ea = 74.95 kJ mol−1, ΔH# = 72.39 kJ mol−1, and ΔS# = −77.74 J mol−1 K−1. The AGH@Ru catalytic system, with a turnover frequency (TOF) of 3.24 min−1 or 194.4 h−1 at 25 °C, also exhibited excellent reusability.
Non-enzymatic electrochemical detection of paraoxon ethyl by differential pulse voltammetry using a disposable graphite pencil electrode
(Elsevier, 2025) Giray Dilgin, Didem; Yücel, Ferhat; Demir, İrem; Dilgin, Yusuf
This work exhibits a nonenzymatic, sensitive, and simple electrochemical determination of paraoxon ethyl (PO-Et) at a bare graphite pencil electrode (GPE), which has several advantages, such as disposability, commercial availability, cost-effectiveness, and no requirement for long-time polishing and preparation steps. Cyclic voltammetric results show that the electroactive aromatic nitro group (Ar-NO2) in the structure of PO-Et is irreversibly reduced to N-hydroxyl amine (Ar-NHOH) by accepting 4e− and 4H+ at −700 mV vs. Ag/AgCl(sat. KCl) in a pH 10.0 Britton Robinson buffer (BRB) solution containing 0.10 M KCl. After that, the produced Ar-NHOH is reversibly oxidized to a nitroso group (Ar-N=O) by giving 2e− and 2H+ at a formal potential of −225 mV. The differential pulse voltammetric method has been proposed for sensitive and selective determination of PO-Et by evaluation of both irreversible nitro group reduction (RedI) and reversible N-hidroxyl amine group oxidation (OxII)/nitroso group reduction (RedII) of PO-Et for the first time. Two linear calibration curves for each peak were obtained with a detection limit of 17.0, 8.0, and 9.0 nM for OxII, RedII, and RedI, respectively. The application of the proposed voltammetric method has been performed in the three different real samples, such as water, soil, and tomato juice, and recovery results close to 100 % demonstrate an acceptable accuracy of the method. In addition, the PO-Et levels in the spiked real samples were determined with a standard spectrophotometric method, and the results have found a good agreement between the proposed electrochemical and standard UV–Vis spectrophotometric methods.

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