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Öğe A review of valorization of agricultural waste for the synthesis of cellulose membranes: Separation of organic, inorganic, and microbial pollutants(Elsevier, 2024) Sharma, Madhu; Bains, Aarti; Dhull, Sanju Bala; Ali, Nemat; Rashid, Summya; Elossaily, Gehan M.; Chawla, Prince; Gökşen, GüldenAgricultural waste presents a significant environmental challenge due to improper disposal and management practices, contributing to soil degradation, biodiversity loss, and pollution of water and air resources. To address these issues, there is a growing emphasis on the valorization of agricultural waste. Cellulose, a major component of agricultural waste, offers promising opportunities for resource utilization due to its unique properties, including biodegradability, biocompatibility, and renewability. Thus, this review explored various types of agricultural waste, their chemical composition, and pretreatment methods for cellulose extraction. It also highlights the significance of rice straw, sugarcane bagasse, and other agricultural residues as cellulose-rich resources. Among the various membrane fabrication techniques, phase inversion is highly effective for creating porous membranes with controlled thickness and uniformity, while electrospinning produces nanofibrous membranes with high surface area and exceptional mechanical properties. The review further explores the separation of pollutants including using cellulose membranes, demonstrating their potential in environmental remediation. Hence, by valorizing agricultural residues into functional materials, this approach addresses the challenge of agricultural waste management and contributes to the development of innovative solutions for pollution control and water treatment.Öğe Innovative approach against cancer: Thymoquinone-loaded PHEMA-based magnetic nanoparticles and their effects on MCF-7 breast cancer(Elsevier, 2024) Yıldırım, Metin; Acet, Ömür; Önal Acet, Burcu; Karakoç, Veyis; Odabaşı, MehmetBreast cancer is most common cancer among women in the World. Thymoquinone (TQ) exhibits a wide range of biological activities such as anticancer, antidiabetic, antimicrobial, analgesic, antioxidant, and anti-inflammatory effects. However, its effectiveness in cancer treatment is hindered by its poor bioavailability, attributed to its limited solubility in water. Hence, novel strategies are required to enhance the bioavailability of TQ, which possesses remarkable anticancer characteristics. The aim of this study is to prepare pHEMA-based magnetic nanoparticles carrying TQ (TQ-MNPs) to improve bioavailability, and therapeutic efficacy against breast cancer. For this purpose, TQ-MNPs were synthesized and characterized with Fourier transform infrared spectrophotometer (FTIR), scanning electron microscopy (SEM), dynamic light scattering (DLS), magnetic field using a vibrating sample magnetometer (VSM). The loading capabilities of synthesized magentic nanostructures were evaluated, and release investigations were conducted under experimental conditions that mimic the cellular environment. The findings of the studies indicated that the TQ carrying capacity of MNPs was deemed satisfactory, and the release efficiency was adequate. MNPs and TQ-MNPs showed biocompatibility against HDFa cells. TQ-MNPs showed stronger anti-proliferative activity against MCF-7 breast cancer cells compared to free TQ (p < 0.05). TQ-MNPs induced apoptosis in MCF-7 breast cancer cells.Öğe Electromyographic analysis of the traditional and spin throwing techniques for goalball games related to ball velocity for selected upper extremity muscles(BMC Sports Science, Medicine and Rehabilitation, 2024) Gökçen, Ayşenur; İnce, Gonca; Alcan, VeyselGoalball is a popular sport among visually impaired individuals, offering many physical and social benefits. Evaluating performance in Goalball, particularly understanding factors influencing ball velocity during throwing techniques, is essential for optimizing training programs and enhancing player performance. However, there is limited research on muscle activation patterns during Goalball throwing movements, needing further investigation to address this gap. Therefore, this study aims to examine muscle activity in sub-elite visually impaired Goalball players during different throwing techniques and visual conditions, focusing on its relationship with ball velocity. Methods: 15 sub-elite Goalball players (2 female, 13 males; mean age of 20.46 ± 2.23 years) participated in the study. Muscle activity was evaluated with the Myo armband, while ball velocity was measured using two cameras and analyzed with MATLAB software. Different visual conditions were simulated using an eye band, and the effects of these conditions on muscle activation and ball velocity were examined. Results: The flexor muscles were found to be more active during the spin throw techniques with the eyes open (p = 0.011). The extensor muscles were found to be more active in the eyes-closed spin throw techniques compared to the eyes-open position (p = 0.031). Ball velocity was found related to the flexor muscles. Interestingly, no significant differences in ball velocity were observed between different throwing techniques or visual conditions (p > 0.05). Conclusions: Ball velocity, one of the performance indicators of the athlete, is primarily related to upper extremity flexor muscle strength rather than visual acuity. It has less visual acuity, but an athlete with more upper-extremity flexor muscle strength will have an advantage in Goalball game. The spin throw technique, which is reported to provide a biomechanical advantage for professional players in the literature, did not provide an advantage in terms of ball velocity for the sub elite players evaluated in our study. This knowledge can inform the development of targeted training programs aimed at improving technique and enhancing ball velocity in Goalball players.Öğe Electrospun nanofiber mats caged the mammalian macrophages on their surfaces and prevented their inflammatory responses independent of the fiber diameter(Nature Portfolio, 2024) Ayaz, Furkan; Demir, Didem; Bölgen, NimetPoly-ε-caprolactone (PCL) has been widely used as biocompatible materials in tissue engineering. They have been used in mammalian cell proliferation to polarization and differentiation. Their modified versions had regulatory activities on mammalian macrophages in vitro. There are also studies suggesting different nanofiber diameters might alter the biological activities of these materials. Based on these cues, we examined the inflammatory activities and adherence properties of mammalian macrophages on electrospun PCL nanofibrous scaffolds formed with PCL having different nanofiber diameters. Our results suggest that macrophages could easily attach and get dispersed on the scaffolds. Macrophages lost their inflammatory cytokine TNF and IL6 production capacity in the presence of LPS when they were incubated on nanofibers. These effects were independent of the mean fiber diameters. Overall, the scaffolds have potential to be used as biocompatible materials to suppress excessive inflammatory reactions during tissue and organ transplantation by caging and suppressing the inflammatory cells.Öğe Antibacterial and antioxidant activity of gold and silver nanoparticles in dextran–polyacrylamide copolymers(Springer Link, 2024) Tkachenko, Anton; Özdemir, Sadin; Tollu, Gülşah; Dizge, Nadir; Ocakoglu, Kasım; Prokopiuk, Volodymyr; Onishchenko, Anatolii; Сhumachenko, Vasyl; Virych, Pavlo; Pavlenko, Vadym; Kutsevol, NataliyaSearch for new antimicrobial agents is of great significance due to the issue of antimicrobial resistance, which nowadays has become more important than many diseases. The aim of this study was to evaluate the toxicity and biological effects of a dextran-graft-polyacrylamide (D-PAA) polymer-nanocarrier with/without silver or gold nanoparticles (AgNPs/D-PAA and AuNPs/D-PAA, respectively) to analyze their potential to replace or supplement conventional antibiotic therapy. The toxicity of nanocomplexes against eukaryotic cells was assessed on primary dermal fibroblasts using scratch, micronucleus and proliferation assays. DPPH (2,2-diphenyl-1-picrylhydrazylradical) assay was used to evaluate the antioxidant capacity of D-PAA, AgNPs/D-PAA and AuNPs/D-PAA. DNA cleavage, antimicrobial and biofilm inhibition effects of nanocomplexes were investigated. Nanocomplexes were found to be of moderate toxicity against fibroblasts with no genotoxicity observed. AgNPs/D-PAA reduced motility and proliferation at lower concentrations compared with the other studied nanomaterials. AgNPs/D-PAA and AuNPs/D-PAA showed radical scavenging capacities in a dose-dependent manner. The antimicrobial activity of AgNPs/D-PAA against various bacteria was found to be much higher compared to D-PAA and AuNPs/D-PAA, especially against E. hirae, E. faecalis and S. aureus, respectively. D-PAA, AgNPs/D-PAA and AuNPs/D-PAA showed DNA-cleaving and biofilm inhibitory activity, while AgNPs/D-PAA displayed the highest anti-biofilm activity. AgNPs/D-PAA and AuNPs/D-PAA were characterized by good antimicrobial activity. According to the findings of the study, AgNPs/D-PAA and AuNPs/D-PAA can be evaluated as alternatives for the preparation of new antimicrobial agents, the fight against biofilms, sterilization and disinfection processes. Our findings confirm the versatility of nanosystems based on dextran-polyacrylamide polymers and indicate that AgNPs/D-PAA and AuNPs/D-PAA can be evaluated as alternatives for the preparation of novel antimicrobial agents.Öğe Synthesis of PES membranes modified with polyurethane–paraffin wax nanocapsules and performance of bovine serum albumin and humic acid rejection(IWA Publishing, 2023) Sert, Buse; Kaya, Gul; Ozay, Yasin; Alterkaoui, Aya; Ocakoglu, Kasım; Dizge, NadirMembrane fouling is a serious handicap of membrane-based separation, as it reduces permeation flux and hence increases operational and maintenance expenses. Polyurethane–paraffin wax (PU/PW) nanocapsules were integrated into the polyethersulfone membrane to manufacture a composite membrane with higher antifouling and permeability performance against humic acid (HA) and bovine serum albumin (BSA) foulants. All manufactured membranes were characterized by scanning electron microscopy (SEM), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), and contact angle. The contact angle of the pristine polyethersulfone (PES) membrane was measured 73.40 + 1.32. With the embedding of nanocapsules, the contact angle decreased to 64.55 + 1.23 for PES/PU/PW 2.0 wt%, and the pure water flux of all composite membranes increased when compared to pristine PES. The pristine PES membrane also has shown the lowest steady-state fluxes at 45.84 and 46.59 L/m2 h for BSA and HA, respectively. With the increase of PU/PW nanocapsule ratio from 0.5 to 1.0 wt%, steady-state fluxes increased from 51.96 to 71.61 and from 67.87 to 98.73 L/m2 h, respectively, for BSA and HA. The results depicted that BSA and HA rejection efficiencies of PU/PW nanocapsules blended PES membranes increased when compared to pristine PES membranesÖğe Development of a Cr2AlC MAX phase/g-C3N4 composite-based electrochemical sensor for accurate cabotegravir determination in pharmaceutical and biological samples(Springer, 2024) Bouali, Wiem; Genc, Asena Ayse; Erk, Nevin; Kaya, Gul; Sert, Buse; Ocakoğlu, KasımA highly sensitive electrochemical sensor is reported that employs a modified electrode for the precise measurement of cabotegravir, a potent anti-HIV drug. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were utilized for this purpose. Electrode modification involved the immobilization of Cr2AlC MAX phase/g-C3N4 onto a glassy carbon electrode (GCE) to enhance its electrocatalytic activity and selectivity for cabotegravir detection. Under the optimal experimental conditions, the working potential (vs. Ag/AgCl) was to 0.93 V. The developed sensor exhibited a good linear relationship in the range 0.05 µM to 9.34 µM with a low limit of detection of 4.33 nM, signifying its exceptional sensitivity. Additionally, it demonstrated successful cabotegravir detection in pharmaceutical formulations and biological samples, achieving an RSD below 3.0%. The recoveries fell within the range 97.7 to 102%, confirming the sensor's potential for real-sample applications. This innovative electrochemical sensor represents a significant advancement, providing a simple, reliable, and sensitive tool for the accurate measurement of cabotegravir. Its potential applications include optimizing drug dosages, monitoring treatment responses, and supporting the development of cabotegravir-based pharmaceutical products, thereby contributing to advancements in HIV therapy and prevention strategies.
