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Full-Text Articles in Physical Sciences and Mathematics
Carbon Quantum Dots And Chitosan-Based Heterogeneous Silver Catalyst For Reduction Of Nitroaromatic Compounds, Farah Sami̇r Sali̇m, İdri̇s Sargin, Gülşi̇n Arslan
Carbon Quantum Dots And Chitosan-Based Heterogeneous Silver Catalyst For Reduction Of Nitroaromatic Compounds, Farah Sami̇r Sali̇m, İdri̇s Sargin, Gülşi̇n Arslan
Turkish Journal of Chemistry
Chitosan plays a crucial role in catalysis, environmental remediation, and sustainable chemistry as a renewable and cationic polysaccharide. Chitosan-based metal catalysts are used in a broad range of chemical transformations. In the study, carbon quantum dots (CQDs) were derived from Momordica charantia fruits by microwave irradiation following a green chemistry approach. Three catalysts were designed: Ag(0)-chitosan, Ag(0)-chitosan-M. charantia fruit powder, and Ag(0)-chitosan-CQDs. The catalyst supports were prepared by stabilizing CQDs or M. charantia powder within the polymeric matrix of chitosan beads. Metallic silver particles were anchored onto glutaraldehyde cross-linked chitosan beads from the aqueous solution of silver nitrate. The …
Investigation Of Boron Nanosized Particles Prepared With Various Surfactants And Chitosan In Terms Of Physical Stability And Cell Viability, Emrah Özakar, Mehmet Semi̇h Bi̇ngöl, Ruki̇ye Sevi̇nç Özakar
Investigation Of Boron Nanosized Particles Prepared With Various Surfactants And Chitosan In Terms Of Physical Stability And Cell Viability, Emrah Özakar, Mehmet Semi̇h Bi̇ngöl, Ruki̇ye Sevi̇nç Özakar
Turkish Journal of Chemistry
Nanosuspensions (NS) are one of the new generation drug carrier forms developed to overcome the deficiencies of drugs with poor water solubility or insolubility and are considered to be one of the most successful approaches to formulate compounds in recent years. Boron nitride (BN) is insoluble in water and chemically more stable than carbon, it offers better biological superiority although the application of carbon structures in the biomedical field has increased in recent years. Chitosan is a polymer with excellent processability and biocompatibility thanks to its high dielectric constant. In addition, chitosan has a high affinity for metal ions. This …
Synthesis Of Modified Nanocomposite Material And Its Use On Removal Of Cesium Fromaqueous Media, Bi̇lal Çeti̇n, Mustafa Özcan, Bektaş Karakelle
Synthesis Of Modified Nanocomposite Material And Its Use On Removal Of Cesium Fromaqueous Media, Bi̇lal Çeti̇n, Mustafa Özcan, Bektaş Karakelle
Turkish Journal of Chemistry
A nanocomposite containing Fe3O4, chitosan (Ch), and hexacyanoferrate (HCF) was synthesized in the form of powder. The physicochemical properties of this nanocomposite are determined using different techniques including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM). The existence of Cs (Cs) ions onto the surface of the nanocomposite was verified by dispersive X-ray spectroscopy (EDX). FTIR spectra confirmed that the nanocomposite was well coordinated. The batch technique was applied to evaluate the influences of initial pH value, temperature, contact time, shaking rate, initial Cs concentration, and competing cations on the efficiency of Cs …
Preparation, Assessment, And Swelling Study Of Amphiphilic Acrylic Acid/Chitosan-Based Semi-Interpenetrating Hydrogels, Mohammad Reza Jozaghkar, Amir Sepehrianazar, Farshid Ziaee, Fakhrosadat Mirtaleb
Preparation, Assessment, And Swelling Study Of Amphiphilic Acrylic Acid/Chitosan-Based Semi-Interpenetrating Hydrogels, Mohammad Reza Jozaghkar, Amir Sepehrianazar, Farshid Ziaee, Fakhrosadat Mirtaleb
Turkish Journal of Chemistry
The aim of this study was to synthesize amphiphilic semi-IPN hydrogels based on acrylic acid (AA) and chitosan (CS) using AIBN as an initiator and N,N?methylene bis acrylamide as a crosslinking agent. The swelling behavior of the hydrogels was evaluated at a variety of pH values, temperature, the salinity of media and time, and the swelling mechanism was investigated using Fickian diffusion and Schott's 2nd-order-kinetics models. FTIR spectroscopy was used to confirm the synthesis of AA/CS hydrogel. The swelling results showed that, in the acidic media, as the CS content increase the hydrogel swelling ratio reduces. It was found that …
Drug Delivery System For Controlled Release Of Empagliflozin From Alginate-Chitosannanocarrier System, Nasim Ramazanzadeh, Nosrat O. Mahmoodi
Drug Delivery System For Controlled Release Of Empagliflozin From Alginate-Chitosannanocarrier System, Nasim Ramazanzadeh, Nosrat O. Mahmoodi
Turkish Journal of Chemistry
biocompatible nanocarrier system was prepared in this research through the reaction of calcium alginate (CA) with chitosan (CS). The structure of developed nanocarriers (CS-CA) was characterized by thermogravimetric analysis (TGA), Fourier transforms infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) atomic force microscopy (AFM), and transmission electron microscopy (TEM). Swelling properties of CS-CA and CA, and their ability for loading and in vitro release of empagliflozin (EMP) were also investigated. The results showed the higher loading capacity of CS-CA compared to CA. For both nanocarriers, the drug release was higher at neutral pH (7.4 and 6.8) …
The Investigation Of Parameters Affecting Ibrutinib Release From Chitosan/ Tripolyphosphate/Carbon Nanofiber Composite Microspheres, Canan Armutcu
The Investigation Of Parameters Affecting Ibrutinib Release From Chitosan/ Tripolyphosphate/Carbon Nanofiber Composite Microspheres, Canan Armutcu
Turkish Journal of Chemistry
This study described the performance of carbon nanofiber modified chitosan (CNF@CS) composite microspheres for the controlled release of the Ibrutinib (IBR) drug. The surface morphology, particle sizes, and functional group contents of the microspheres were characterized by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron, and optical microscopy measurements. The obtained data demonstrated that the addition of CNF to the microsphere increased the encapsulation efficiency of the IBR while allowing the controlled and gradual release of the drug. In terms of the encapsulation efficiency and drug release rate, IBR@CS/TPP/CNF microspheres, achieving drug encapsulation efficiency of 83.09%, have the most …
Box-Behnken Design For Removal Of Uranium(Vi) From Aqueous Solution Using Poly(Ethylene Glycol) Based Dicationic Ionic Liquid Impregnated Chitosan, Süleyman İnan, Taşkin Mumcu, Serap Seyhan Bozkurt
Box-Behnken Design For Removal Of Uranium(Vi) From Aqueous Solution Using Poly(Ethylene Glycol) Based Dicationic Ionic Liquid Impregnated Chitosan, Süleyman İnan, Taşkin Mumcu, Serap Seyhan Bozkurt
Turkish Journal of Chemistry
Poly(ethylene glycol) bis(methylimidazolium) di[bis(trifluoromethylsulfonyl)imide] was synthesized as an ionic liquid and impregnated onto chitosan. The removal of uranium(VI) ions from aqueous solution was investigated with batch sorption tests using ionic liquid impregnated chitosan. Response surface methodology based on 3 level Box-Behnken design was applied to analyze the effect of initial pH (4-6), initial concentration (20-60 mg L$^{-1})$, contact time (15-105 min), and temperature (30-50 $^{\circ}$C C) on the uptake capacity of uranium(VI). Main effect of initial concentration, quadratic effect of contact time, and dual effect of initial pH and contact time were found statistically significant based on analysis of variance …
Evaluation Of A Novel Nanocrystalline Hydroxyapatite Powder And A Solid Hydroxyapatite/Chitosan-Gelatin Bioceramic For Scaffold Preparation Used As A Bone Substitute Material, Sharmin Rahman, Kazi Hanium Maria, Mohammad Saif Ishtiaque, Arijun Nahar, Harinarayan Das, Sheikh Manjura Hoque
Evaluation Of A Novel Nanocrystalline Hydroxyapatite Powder And A Solid Hydroxyapatite/Chitosan-Gelatin Bioceramic For Scaffold Preparation Used As A Bone Substitute Material, Sharmin Rahman, Kazi Hanium Maria, Mohammad Saif Ishtiaque, Arijun Nahar, Harinarayan Das, Sheikh Manjura Hoque
Turkish Journal of Chemistry
Artificially fabricated hydroxyapatite (HAP) shows excellent biocompatibility with various kinds of cells and tissues which makes it an ideal candidate for a bone substitute material. In this study, hydroxyapatite nanoparticles have been prepared by using the wet chemical precipitation method using calcium nitrate tetra-hydrate [Ca(NO$_{3})_{2}$.4H$_{2}$O] and di-ammonium hydrogen phosphate [(NH$_{4})_{2}$HPO$_{4}$] as precursors. The composite scaffolds have been prepared by a freeze-drying method with hydroxyapatite, chitosan, and gelatin which form a 3D network of interconnected pores. Glutaraldehyde solution has been used in the scaffolds to crosslink the amino groups ($\vert $NH$_{2})$ of gelatin with the aldehyde groups ($\vert $CHO) of chitosan. …
Synthesis And Characterization Of Magnetic Amidoximated Chitosan-G Poly(Polyacrylonitrile)/Laponite Rd Nanocomposites With Enhanced Adsorption Capacity For Cu$^{2+}$, Gholam Reza Mahdavinia, Ebrahim Shokri
Synthesis And Characterization Of Magnetic Amidoximated Chitosan-G Poly(Polyacrylonitrile)/Laponite Rd Nanocomposites With Enhanced Adsorption Capacity For Cu$^{2+}$, Gholam Reza Mahdavinia, Ebrahim Shokri
Turkish Journal of Chemistry
Magnetic amidoximated nanocomposites based on a combination of chitosan and magnetic laponite RD were prepared and examined for the removal of Cu$^{2+}$ from aqueous solutions. Magnetic laponite RD was prepared by an in situ method. In order to prepare magnetic amidoximated nanocomposites, acrylonitrile was grafted to chitosan in the presence of magnetic laponite RD. Then the nitrile pendants on magnetic chitosan-g-polyacrylonitrile/laponite RD (mChtioPANLap) were converted to amidoxime groups. We developed a polyamidoximated magnetic nanocomposite based on a mixture of chitosan/laponite RD, possessing a high adsorption capacity for Cu$^{2+}$. By introducing magnetic laponite RD the adsorption capacity of nanocomposites for Cu$^{2+}$ …
Improvement Of Electrochemical And Structural Properties Of Polycarbazole By Simultaneous Electrodeposition Of Chitosan, Di̇dem Balun Kayan, Veysel Polat
Improvement Of Electrochemical And Structural Properties Of Polycarbazole By Simultaneous Electrodeposition Of Chitosan, Di̇dem Balun Kayan, Veysel Polat
Turkish Journal of Chemistry
Polycarbazole/chitosan composite materials were synthesized electrochemically at various loadings of chitosan (Chi). Their electrochemical, structural, thermal, and morphological characterizations were investigated by cyclic voltammetry, chronoamperometry, electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy, thermal gravimetry, and scanning electron microscopy. Further electrical conductivity was measured using a four-point probe technique. The electrochemical results showed that the electrical conductivity of the polymeric composite film was increased by increasing the amount of Chi in the electrolyte medium. The as-prepared composite films exhibited enhanced electrical conductivity and structural properties of polycarbazole due to the presence of Chi in the composite films.
Electrochemical Monitoring Of The Interaction Between Mitomycin C And Dna At Chitosan--Carbon Nanotube Composite Modified Electrodes, Pembe Ece Canavar, Ece Ekşi̇n, Kadri̇ye Arzum Erdem Gürsan
Electrochemical Monitoring Of The Interaction Between Mitomycin C And Dna At Chitosan--Carbon Nanotube Composite Modified Electrodes, Pembe Ece Canavar, Ece Ekşi̇n, Kadri̇ye Arzum Erdem Gürsan
Turkish Journal of Chemistry
Single-walled carbon nanotube (CNT) and chitosan composite (chitosan*CNT) based sensors were developed as DNA biosensors, and then they were applied for electrochemical investigation of the interaction between the anticancer drug mitomycin C (MC) and DNA. The oxidation signals of MC and guanine were monitored before and after the interaction process by differential pulse voltammetry (DPV). The DPV results were in good agreement with those of electrochemical impedance spectroscopy (EIS). Analytical parameters such as DNA concentration, MC concentration, and MC interaction time with DNA were optimized. The detection limits were 6.85 \mu g/mL for DNA and 11.01 \mu g/mL for MC.
Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova
Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova
Turkish Journal of Chemistry
A decavanadate/chitosan complex was synthesized by crosslinking chitosan with decavanadate anions at a pH of 3. The materials were characterized by Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), absorption spectroscopy (UV-Vis), and transmission electron microscopy (TEM). The spectroscopic results indicated that the decavanadate/chitosan complex was successfully obtained as result of an ionic crosslinking of the chitosan with decavanadate anions.
Inclusion And Release Of Theophylline From Chitosan Based Microparticles, Niculina Popa, Ovidiu Novac, Lenuta Profire, Doina Hritcu, Marcel Ionel Popa
Inclusion And Release Of Theophylline From Chitosan Based Microparticles, Niculina Popa, Ovidiu Novac, Lenuta Profire, Doina Hritcu, Marcel Ionel Popa
Turkish Journal of Chemistry
Chitosan (CS) based microparticles for controlled release of theophylline (THP) were obtained by ionic gelation. The microparticles were characterized by laser diffraction analysis (particle size), scanning electron microscopy (SEM), FTIR spectroscopy, and thermogravimetric analysis. The average diameter of the CS-THP microparticles was 182 \mu m. The FTIR spectra confirmed that new hydrogen bonds had formed between the carbonylic group belonging to THP and the amino group of CS, while the thermogravimetric analysis showed a modified stability in the obtained particles and confirmed the presence of an interaction between the drug and CS. The THP release process was monitored for up …
Preparation And Characterization Of Magnetic Chitosan Nanospheres, Doina Hritcu, Marcel I. Popa, Nuculina Popa, Vasile Badescu, Vera Balan
Preparation And Characterization Of Magnetic Chitosan Nanospheres, Doina Hritcu, Marcel I. Popa, Nuculina Popa, Vasile Badescu, Vera Balan
Turkish Journal of Chemistry
A method for the preparation of magnetite/chitosan composite nanoparticles was developed. Colloidal magnetite particles (Fe_3O_4 produced by co-precipitation and stabilized in suspension by adding a non-ionic surfactant (Pluronic F127) were subsequently covered with a layer of chitosan (CS) prepared by ionotropic gelation using sodium tripolyphosphate (STPP) as a crosslinking agent. The products were characterized in terms of the following parameters: size distribution and \zeta-potential (by laser diffraction analysis), surface morphology (TEM), composition (FTIR, elemental analysis), magnetic properties (magnetic susceptibility analysis), and concentration of surface functional groups (potentiometric titration). The synthesis parameters were optimized for obtaining uniformly distributed colloidally stable, biocompatible …
Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia
Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia
Turkish Journal of Chemistry
Acrylamide (AAm) monomer was directly grafted onto chitosan using ammonium persulfate (APS) as an initiator and methylenebisacrylamide (MBA) as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-poly(acrylamide) (chitosan-g-PAAm) with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution (0.15 mol/L NaCl, CaCl_2 and AlCl_3) was examined. Swelling capacity …
External Mass Transfer Studies During The Adsorptions Of Some Dyestuffs And P-Nitrophenol Onto Chitosan From Aqueous Solution, İlhan Uzun, Fuat Güzel
External Mass Transfer Studies During The Adsorptions Of Some Dyestuffs And P-Nitrophenol Onto Chitosan From Aqueous Solution, İlhan Uzun, Fuat Güzel
Turkish Journal of Chemistry
The effect of temperature on the adsorptions of some dyestuffs [orange II (O-II), crystal violet (CV) and reactive blue 5 (RB5)] and an ideal adsorbate p-nitrophenol (PNP) by chitosan (Sigma C 3646) from aqueous solution was investigated. The experimental data related to adsorption isotherms were applied to linear forms of the equations that they fitted, and isotherm constants were calculated. Since the isotherm curves obtained for the adsorptions of O-II and CV by chitosan fitted the Langmuir adsorption isotherm, the Langmuir constants (q_m and b) related to the adsorption isotherms of these dyestuffs together with their kinetical data at different …
Stabilization Of Papain By Modification With Chitosan, Ali̇ Kilinç, Seçi̇l Önal, Azmi̇ Telefoncu
Stabilization Of Papain By Modification With Chitosan, Ali̇ Kilinç, Seçi̇l Önal, Azmi̇ Telefoncu
Turkish Journal of Chemistry
Papain (EC 3.4.22.2) was immobilized on chitosan by adsorption and subsequent cross-linking with glutaraldehyde. The immobilized papain displayed a lower specific activity than did the native enzyme. The thermal stability of the immobilized papain, relative to that of the free enzyme, was markedly increased. The storage stability of the conjugated enzyme was enhanced such that more than 85% of the initial activity remained after a month storage at 45°C. The optimum pH of immobilized papain was shifted to the acidic region and enzyme stability was increased at pH levels below 3.5.
Adsorption Of Some Heavy Metal Ions From Aqueous Solution By Activated Carbon And Comparison Of Percent Adsorption Results Of Activated Carbon With Those Of Some Other Adsorbents, İlhan Uzun, Fuat Güzel
Adsorption Of Some Heavy Metal Ions From Aqueous Solution By Activated Carbon And Comparison Of Percent Adsorption Results Of Activated Carbon With Those Of Some Other Adsorbents, İlhan Uzun, Fuat Güzel
Turkish Journal of Chemistry
In this study, removal of some heavy metals ions (Mn^{2+}, Fe^{2+}, Ni^{2+} and Cu^{2+}) from aqueous solution by adsorption was investigated. For this purpose, high-grade MnSO_4.H_2O, FeSO_4.7H_2O, NiSO_4.7H_2O and CuSO_4.5H_2O were used as heavy metal samples. The commercial activated carbon (Merck 2514), chitosan and agar were used as adsorbents. The pH of each solution was not controlled. This is because the net interaction between the adsorbent and the heavy metal could be disturbed by the buffer solution. Therefore, all experiments were carried out in a pH range from 5.3 to 5.5. The equilibrium adsorption contact times were determined for M …