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Öğe Biodegradation of 2,4,6-Trinitrotoluene (TNT) with Bacteria Isolated from TNT-polluted Waste Pink Water(Budapest Univ Technology Economics, 2019) Gok, Zehra Gun; Inal, Murat; Yigitoglu, MustafaIn this study, bacterial strains that can use TNT as a nitrogen source isolated from TNT contaminated pink water. We isolated 5 bacterial strains and the isolated bacteria were cultured in medium containing TNT and TNT degradation capacities of isolates were determined by spectrophotometric analysis. According to the results of the analysis that have done, 3 bacterial isolates that have high TNT degradation capacity were selected and the isolates were identified with firstly Gram-staining then with 16S rRNA sequence analysis method. According to the sequence of 16S rRNA, water isolates were identified as Stenotrophomonas maltophilia (SU K2), Klebsiella pneumoniae (SU K3), Raoultella planticola (SU K4). During the TNT degradation studies, at the end of 24 h incubation time, in the medium containing 100 mg/L TNT, TNT degradation rate for SU K2, SU K3 and SU K4 were determined 70 %, 96 % and 93 % respectively. 4-aminodinitrotoluene and 2-aminodinitrotoluene accumulations were detected in the culture medium of all isolates as intermediate products formed during the degradation of TNT by HPLC analysis. Additionally, nitrite accumulation was detected in the culture medium of all isolates and the influence of temperature and pH on the degradation of TNT was also investigated. It was determined that SU K2 isolates have the highest TNT degradation capacity at 35 degrees C, the others have at 30 degrees C and all isolates degraded TNT fastest at pH 7. The results of the study show that the new isolates can be useful for the removal of TNT in a wastewater treatment system.Öğe CO2 laser machining for microfluidics mold fabrication from PMMA with applications on viscoelastic focusing, electrospun nanofiber production, and droplet generation(Elsevier Science Inc, 2021) Guler, Mustafa Tahsin; Inal, Murat; Bilican, IsmailIn this study, a new method for the fabrication of polydimethylsiloxane (PDMS) microchannels through the replication of plexiglass molds was developed. A plexiglass slab is machined with CO2 laser in the raster mode to produce the mold for the PDMS casting. Then, the PDMS replica of the mold is plasma bonded to a substrate by applying more pressure than standard to overcome the surface roughness inherited from the laser machining process. Depending on the channel complexity, a ready to cast mold in the size of a glass slide can be achieved in 5-20 min, including the design, machining, and cleaning steps. This fully automated and cost-effective mold making method proved to be the fastest among all methods, and it enables up to 2.5 aspect ratio microchannels, down to a width of 60 mm, and a height of 23 mm. The raster mode of the laser provides features lower, in size, then the laser beam waist radius. The produced microchannels were validated using several applications, such as droplet generation, nanofiber production, and viscoelastic microparticle focusing. (c) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.Öğe Controlled release of indomethacin from crosslinked alginate beads(Walter De Gruyter Gmbh, 2008) Inal, Murat; Yigitoglu, Mustafa; Isiklan, NuranBeads of the sodium alginate ( NaAlg) were prepared by dropping aqueous sodium alginate ( NaAlg) into glutaraldehyde ( GA) as a crosslinker and HCl as a catalyst mixture solution. Beads prepared were used to deliver a model non-steroid, anti-inflammatory drug, indomethacin ( IM). The beads were characterized with Fourier transform infrared spectroscopy ( FTIR), differential scanning calorimetry ( DSC) and scanning electron microscopy ( SEM). Chemical stability of the IM after encapsulation into beads was confirmed by FTIR. SEM photograph indicated that alginate bead has spherical shape and rough surface. Preparation conditions of the beads were optimized by considering the percentage of entrapment efficiency, swelling capacity of the beads, particle size and their release data. In vitro release studies were performed in simulated gastric fluid ( pH 1.2) for the initial 2 h, followed by simulated intestinal fluid ( pH 7.4) for 4 h. Effects of variables such as, GA concentration, exposure time to GA, drug/ polymer ( d/ p) ratio and percentage of HCl on the release of the IM were investigated. It was observed that, IM release from the beads decreased with increasing GA concentration, exposure time to GA, d/ p ratio and percentage of HCl. The highest cumulative IM release obtained at the end of 6 h was 68% for alginate beads which were prepared with 0.5% HCl. On the other hand the least cumulative IM release obtained was to be 20 % for alginate beads which were prepared with 30 min exposure time to GA. In order to understand the crosslinking of the polymeric matrix, the molar mass between crosslinks were calculated using the swelling parameters. It was also found from the swelling experiments that swelling degree of the beads increases with increase in the temperature. The release data have been fitted to an empirical equation to estimate the kinetic parameters. The diffusion coefficient was also calculated for the transport of the drug through the polymeric beads. Values of these parameters were found to be consistent with the release data.Öğe Development and characterization of orodispersible films containing amlodipine besylate and rosuvastatin calcium based on electrospun fibers(Elsevier, 2024) Muratoglu, Semsi; Inal, Murat; Gulsun, Tugba; Sahin, SelmaAmlodipine besylate (AML) and rosuvastatin calcium (ROS) are commonly used in the treatment of cardiovascular diseases such as hypertension, dyslipidemia, and coroner artery disease. Orodispersible films (ODFs) have received considerable attention in pharmaceutical development studies as they significantly improve patient compliance. The aim of this study was to develop an ODF formulation containing AML and ROS simultaneously as an electrospun fiber fixed dose preparation. Polymer solutions were evaluated for surface tension, viscosity, and conductivity properties. Preformulation studies were conducted to optimize the electrospinning process. Two different formulations, designated ODF-1 and ODF-2 were the focus of this study. Fiber characterization studies, such as scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), mechanical properties were performed to assess these two formulations. Furthermore, ODF characterizations, such as disintegration and wetting time, homogeneity of contents, and in vitro dissolution studies were carried out. All formulations exhibited suitable mechanical properties, facilitating easy storage and handling. ODF characterizations revealed rapid disintegration and wetting times for all formulations with over 90 % dissolution in 5 min for both AML and ROS. The overall evaluation of all experiments suggests that ODF-1 may more desirable mechanical properties and a more stable dissolution profile compared to ODF-2. Furthermore, individual ODFs loaded with AML or ROS (AML-ODF-1 and ROS-ODF-1) were prepared by ODF-1 preparation method and then characterized to compare the results with fixed dose ODF results. In conclusion, a promising formulation strategy has been developed to obtain an electrospun fiber ODF formulation containing AML and ROS that is reproducible and suitable for industrial production.Öğe Effective Removing of Remazol Black B by the Polyacrylamide Cryogels Modified with Polyethyleneimine(Springer, 2022) Gun Gok, Zehra; Inal, MuratIn this study, modified polyacrylamide (PAAm) cryogels with high dye holding capacity were synthesized with an easily and cheaply process and adsorption of Remazol Black B (RBB) with the synthesized materials was investigated. Firstly, PAAm cryogels were synthesized with free radical cryo-copolymerization method and they were modified with Hofmann reaction to form amine groups in the structure of the cyrogels. Then, to increase the removal efficiency of cryogels, polyethylenimine (PEI) molecules were crosslinked onto the cryogels via NH2 groups present in the PAAm gels modified by the Hofmann reaction. The original and modified cryogels were characterized with fourier transformed infrared spectroscopy, C-13 nuclear magnetic resonance spectroscopy, scanning electron microscopy and thermogravimetric analysis. The point of zero charge (pH(pzc)) of the modified cryogels was found to be 7.13 and RBB removing capabilities of PEI-modified PAAm cryogels were investigated at pH between 2 and 7. In addition, the adsorption treatments were performed at different process time, incubation temperature, initial dye concentration and adsorbent amount to find maximum removal capacity of the adsorbent. The modified cryogels adsorbed maximum amount of RBB at pH 2 and the sorption process reached equilibrium in 6 h. It was observed that the adsorption efficiency did not change much with the increase in temperature. The maximum RBB removal capacity of the modified cyrogels was determined to be 201 mg/g when the initial RBB concentration was 200 mg/L, treatment time was 6 h at pH 2. Moreover, the adsorption of RBB dye with the modified cryogels takes place with a second order kinetic and RBB dye adsorption data showed compliance with the Langmuir isotherm. The findings of the study expose that the obtained PEI-modified PAAm cryogels are a hopeful material for RBB removal in aqueous environment.Öğe Electrospun nanofiber drug delivery systems and recent applications: An overview(Elsevier, 2024) Muratoglu, Semsi; Inal, Murat; Akdag, Yagmur; Gulsun, Tugba; Sahin, SelmaFiber technology plays a significant role in advancing drug research. While developing drug delivery systems, nanofiber technology has gained importance due to its high surface area to volume ratio and porosity. The most preferred nanofiber production method is the electrospinning method. This review focuses on electrospun nanofiber drug delivery systems, including analysis of critical process parameters affecting electrospinning and nanofiber properties. Moreover, the design strategies for nanofiber drug delivery systems are explored, including equipment preferences and design types. Given to these design strategies, it is possible to design either nanofiber mat or nanofiber itself. It has been shown that a tailor-made drug delivery system can be prepared using axialbased nozzles and other equipment options. In addition, the prominent features and usage areas of frequently used polymers are mentioned. General characterization studies of post-production nanofibers are discussed. Examples of areas of use for pharmaceutical purposes are presented. Finally, drug release kinetics were evaluated on electrospun nanofiber drug delivery systems. As a result of exhaustive evaluations, various effective applications in the literature have been shown to achieve remarkable results such as drug release manipulation, drug targeting, self-assembling formulation strategies. Therefore, it is clear that in the field of electrospun nanofiber technology, it is possible to modify all the process options and develop a unique drug delivery product, thanks to a comprehensive evaluation of the critical quality parameters of the drug product.Öğe Graft copolymerization of itaconic acid onto sodium alginate using benzoyl peroxide(Elsevier Sci Ltd, 2010) Isiklan, Nuran; Kursun, Fatma; Inal, MuratGraft copolymers of sodium alginate (NaAlg) with itaconic acid (IA) were prepared in aqueous solution using benzoyl peroxide (BPO) as the initiator. Grafted copolymers (NaAlg-g-PIA) were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy scanning electron, microscopy and thermogravimetric analysis. The grafting parameters, including the graft yield (GY%) of the graft copolymer and the grafting efficiency (GE%) of the reaction were evaluated comparatively. The effects of the reaction variables such as the reaction time, temperature, percentage of sodium alginate, monomer and initiator concentrations on these parameters were studied. It was observed that GY and GE first increased and then decreased with increasing polymerization temperature, concentrations of IA, and BPO. The optimum grafting conditions for maximum graft yield were obtained with reaction time of 1 h, reaction temperature of 85 degrees C. IA concentration of 1.38 M. BPO concentration of 1.82 x 10(-2) M and percentage of NaAlg 1.5 g/dL. (C) 2009 Elsevier Ltd. All rights reserved.Öğe Graft Copolymerization of Itaconic Acid onto Sodium Alginate Using Ceric Ammonium Nitrate as Initiator(John Wiley & Sons Inc, 2009) Isiklan, Nuran; Kursun, Fatma; Inal, MuratGraft copolymers of sodium alginate (NaAlg) with itaconic acid (IA) were prepared in aqueous solution using ceric ammonium nitrate (CAN) as the redox initiator under N(2) atmosphere. The carboxylic acid groups of IA were neutralized with sodium hydroxide before grafting process. Grafted copolymers as sodium salts (NaAlg-g-PIA) were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, intrinsic viscosity measurement, differential scanning calorimetry, and thermogravimetric analysis. The graft yield (GY %) of the graft copolymer and the grafting efficiency (GE %) of the reaction were evaluated comparatively. The effects of the reaction variables such as the reaction time, temperature, percentage of NaAlg, monomer and initiator concentrations on these parameters were studied. It was observed that GY% and GE% increased and then decreased with increasing concentrations of IA and polymerization temperature. The optimum grafting conditions for maximum GY were obtained with a reaction time of 5 h, reaction temperature of 30 degrees C, IA concentration of 0.23 M, CAN concentration of 9.12 X 10(-2) M and percentage of NaAlg 0.5 g/dL. The overall activation energy for the grafting was also calculated to be 1135 cal/mol. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 40-48, 2009Öğe Improvement of Bioethanol Productivity of Immobilized Saccharomyces Bayanus with Using Sodium Alginate-Graft-Poly(N-Vinyl-2-Pyrrolidone) Matrix(Springer, 2012) Inal, Murat; Yigitoglu, MustafaIn this study, immobilization conditions and bioethanol production characteristics of immobilized Saccharomyces bayanus were investigated into sodium alginate-graft-poly(N-vinyl-2-pyrrolidone; NaAlg-g-PVP) matrix. The matrix that crosslinked with calcium clorid was used for immobilization of S. bayanus. Bioethanol productivity of the NaAlg-g-PVP matrix was found to increase from 4.21 to 4.84 gL(-1) h(-1) when compared with the convential sodium alginate matrix. The production of bioethanol was affected by initial glucose concentration and percentage of immobilized cell beads in fermentation medium. Bioethanol productivity was increased from 3.62 to 4.84 gL(-1) h(-1) while the glucose concentration increasing from 50 to 100 gL(-1). Due to the increase in percentage from 10 to 20 % of immobilized cell beads in the fermentation medium, bioethanol productivity was increased from 4.84 to 8.68 gL(-1) h(-1). The cell immobilized NaAlg-g-PVP beads were protected 92 % of initial activity after six repeated fermentation.Öğe pH responsive itaconic acid grafted alginate microspheres for the controlled release of nifedipine(Elsevier Sci Ltd, 2011) Isiklan, Nuran; Inal, Murat; Kursun, Fatma; Ercan, GuldenA series of pH responsive alginate-g-poly(itaconic acid) (NaAlg-g-PIA) microspheres were prepared as drug delivery matrices of nifedipine cross-linked by glutaraldehyde (GA) in the hydrochloric acid catalyst. Graft copolymers of sodium alginate with itaconic acid were synthesized using ceric ammonium nitrate. The chemical stability of the nifedipine after encapsulation into microspheres was confirmed by FTIR, DSC and X-RD analysis. The preparation conditions of the NaAlg-g-PIA microspheres such as graft yield, GA concentration, exposure time to GA and drug amount were optimized by considering the percentage entrapment efficiency, particle size, swelling capacity and their release data. The results showed that NaAlg-g-PIA microspheres are pH responsive. The release of nifedipine from grafted microspheres was slower for the pH 1.2 solution than that of the pH 7.4 buffer solution. It has been observed that an increase in exposure time, drug amount, GA and NaAlg-g-PIA concentrations causes a decrease in the nifedipine release from the microspheres, whereas an increase in graft yield leads to an increase in the nifedipine release. (C) 2010 Elsevier Ltd. All rights reserved.Öğe Production and characterization of bactericidal wound dressing material based on gelatin nanofiber(Elsevier, 2019) Inal, Murat; Mulazimoglu, GokceGelatin is a biocompatible and biodegradable natural polymer obtained by collagen. Gelatin nanofibers meet all the necessary requirements when used as wound dressing material. However, their lack of antimicrobial properties limits their use. The purpose of this study is to expand the field of use of gelatin by providing it with antimicrobial properties. For this purpose, poly([2-(methacryloyloxy)ethyl] trimethylammonium chloride) (PMETAC), was used. In this study, the polymers were dissolved in formic acid-acetic acid and nanofibers were synthesized by electrospinning. The obtained nanofibers were characterized with SEM, FTIR, and TGA. The antibacterial effect, degradation tests, and cell viability, adhesion and proliferation were investigated. The SEM studies show that the nanofibers are homogeneous and smooth. At the end of 14 days, all nanofibers lost >90% of their mass. The nano fibers containing PMETAC showed good bactericidal activity against Staphylococcus aureus, Escherichia coli, methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii. mTT test demonstrated that low doses of the nanofibers were biocompatible. The cell adhesion study has been shown that many cells attachment and proliferate on the surface of nanofibers. It has been found that the obtained nanofibers can be used safely and effectively as antimicrobial wound dressing material. (C) 2019 Elsevier B.V. All rights reserved.Öğe Production of 2-hydroxyethyl methacrylate-g-poly(ethylene terephthalate) nanofibers by electrospinning and evaluation of the properties of the obtained nanofibers(WILEY, 2020) Gok, Zehra Gun; Inal, Murat; Bozkaya, Ogun; Yigitoglu, Mustafa; Vargel, IbrahimNanofiber production was investigated from poly(ethylene terephthalate) (PET) polymers functionalized with hydroxyethyl methacrylate (HEMA) by grafting of HEMA monomers onto the PET fibers. HEMA grafted PET (PET-g-HEMA) copolymers were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy. PET and PET-g-HEMA were dissolved in trifluoroacetic acid and nanofibers were obtained by electrospinning. It was found that the PET and PET-g-HEMA polymers having grafting yield 20 and 55% could be converted to continuous, smooth, and beadles nanofibers. For characterization of the nanofiber membranes, thermogravimetric analysis, differential scanning calorimeter analysis, surface contact angle measurement, porosity analysis, and mechanical tests were applied. When compared with the original PET nanofibers, the thermal properties and degradation process of PET-g-HEMA nanofibers changed according to the amount of HEMA present in the structure of nanofibers. The contact angles of the nanofibers obtained from PET-g-HEMA polymers decreased whereas the water retention ability of the nanofibers increased compared to original PET nanofibers. The porosity of PET-g-HEMA nanofibers was found be high compared to PET nanofibers and whereas the mechanical properties of PET was higher than PET-g-HEMA nanofibers. The obtained nanofibers can be used in many fields such as biomaterial applications.Öğe Production of bioethanol by immobilized Saccharomyces Cerevisiae onto modified sodium alginate gel(Wiley-Blackwell, 2011) Inal, Murat; Yigitoglu, MustafaBACKGROUND: Microbial bioethanol production is an important option in view of the finite global oil reserves. Bioethanol fermentation was carried out using immobilized microorganisms (Saccharomyces cerevisiae, Zymomonas mobilis, Pichia stipitis, etc.), which has many advantages compared with the use of free cells. Various support materials have been used for bioethanol fermentation, and alginate gels have been one of the most widely used matrices for cell entrapment. The aim of this study was increased bioethanol production by Saccharomyces cerevisiae immobilized on alginate gels. First, N-vinyl-2-pyrrolidone was grafted onto sodium alginate. Then, the properties of ethanol production were investigated using the matrix obtained. RESULTS: The performance of ethanol fermentation was affected by calcium chloride concentration, N-vinyl-2-pyrrolidone grafted onto the sodium alginate, sugar concentration and the percentage of immobilized cell beads. These effects were optimized to give maximum ethanol production. Ethanol production was accelerated when sodium alginate polymer was modified with N-vinyl-2-pyrrolidone. The maximum concentration, productivity and yield of ethanol were 69.68 g L(-1), 8.71 g L(-1) h(-1) and 0.697 g g(-1), respectively. CONCLUSION: The new polymeric matrix, when compared with sodium alginate, showed better ethanol production due to the hydrophilic property of N-vinyl-2-pyrrolidone. The results suggest that the proposed method for immobilization of Saccharomyces cerevisiae has potential in industrial applications of the ethanol production process. (C) 2011 Society of Chemical IndustryÖğe Removal of various anionic dyes using sodium alginate/poly(N-vinyl-2-pyrrolidone) blend hydrogel beads(Springer, 2015) Inal, Murat; Erduran, NuranIn this study, novel blend hydrogel beads were prepared for the use in removal of anionic textile dyes due to their hazardous impact to nature. Sodium alginate and sodium alginate/poly(N-vinyl-2-pyrrolidone) beads were prepared by gelation method into calcium chloride solution. Prepared blend beads were characterized by TGA and FTIR analysis, and they were successfully used in adsorption of the reactive red-120 (RR), cibacron brilliant red 3B-A (CBR) and remazol brilliant blue R (RBB) in batch system. The effects of various parameters such as pH, initial dye concentration, contact time and temperature onto adsorption were investigated. The maximum adsorption capacities were found 116.8, 73.3 and 55.3 mg g(-1) for RR, CBR and RBB, respectively. The adsorption of dyes was well described by pseudo-second-order kinetics and Langmuir isotherm. Thermodynamic parameters indicated that the adsorption is spontaneous and exothermic. These results have shown that blend hydrogel beads can be effectively used as adsorbent in the removal of dyes from harmful wastewaters.
