Yazar "Ozdemir, Sadin" seçeneğine göre listele

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    Anoxybacillus flavithermus loaded y-Fe2O3 magnetic nanoparticles as an efficient magnetic sorbent for the preconcentrations of Cu(II) and Mn(II)
    (Pergamon-Elsevier Science Ltd, 2022) Ozdemir, Sadin; Turkan, Zeynep; Kilinc, Ersin; Altuner, Elif Esra; Sen, Fatih
    It was hypothesized that-iron( oxide nanoparticles (y-Fe2O3 NPs) functionalized with Anoxybacillus flavithermus (A. flavithermus) as an effective magnetic sorbent for the preconcentrations of toxic metal ions. It is clear to conclude that the main novelty of this study is that y-Fe2O3 NPs loaded with A. flavithermus is selective-specific for Cu(II), Mn(II). Structural functional groups of the samples were elucidated by FTIR, and SEM. Significant experimental parameters were investigated in detail. 0.2 mL min(-1) of flow rate, 5 mL of 1 M of hydrochloric acid as eluent, 150 mg biogenic mass sample, and 150 mg y-Fe2O3 NPs for supporting material were found as the best conditions. This developed method has been tested and verified using certified and standard reference materials. As a result of the studies, the pre-concentration factor of the Cu(II), Mn(II) metals was calculated as 40. All measurements showed that the developed solid-phase extraction (SPE) columns are available for 32 cycles. The use of y-Fe2O3 NPs equipped with A. flavithermus as an effective magnetic sorbent for the first measurements of ions was thoroughly studied. In order of the biosorption capacities were calculated as 26.0, and 30.3 mg/g for Cu (II), Mn(II), respectively. The developed method for specifying the samples showed excellent to excellent results.
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    Anoxybacillus sp. SO B1-Immobilized Amberlite XAD-16 for Solid-Phase Preconcentration of Cu(II) and Pb(II) and Their Determinations by Flame Atomic Absorption Spectrometry
    (Taylor & Francis Inc, 2015) Oral, Elif Varhan; Ozdemir, Sadin; Dolak, Ibrahim; Okumus, Veysi; Dundar, Abdurrahman; Ziyadanogullari, Berrin; Aksoy, Zehra
    A new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1-immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0ml of 1.0mol L-1 HCI and 10.0ml of 0.25mol L-1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 +/- 1.57% and 100.3 +/- 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3s, N = 10) were found to be 0.8 and 1.6 mu g L-1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbakir and Elazig, Lake of Hazar in Elazig, and tap water in Diyarbakir. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar).
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    Antioxidant Properties of Cultured Mycelia from Four Pleurotus Species Produced in Submerged Medium
    (Taylor & Francis Inc, 2013) Dundar, Abdurrahman; Okumus, Veysi; Ozdemir, Sadin; Yildiz, Abdunnasir
    The ethanolic extracts of dried cultured mycelia of Pleurotus ostreatus, Pleurotus eryngii, Pleurotus florida, and Pleurotus sajor-caju were analyzed for antioxidant activity in different systems. Tests used are as follows: reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, metal chelating activitiy, etc.; total phenolic content was determined. The percentage inhibition of P. ostreatus, P. eryngii, P. florida, and P. sajor-caju at 20 mg/mL concentration on peroxidation in a -carotenelinoleic acid system was 57.19, 60.68, 62.12, and 58.81%, respectively. The reducing power of P. eryngii was higher than the other samples, and its value was 0.86 at 10 mg/mL concentration. P. ostreatus and P. sajor-caju proved to be better at scavenging superoxide anion radicals than the P. eryngii and P. florida. In the scavenging effect of DPPH radical test, P. ostreatus showed the highest activity potential and P. sajor-caju showed the strongest metal chelating capacity.
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    Application of magnetized fungal solid phase extractor with Fe2O3 nanoparticle for determination and preconcentration of Co(II) and Hg(II) from natural water samples
    (Elsevier Science Bv, 2018) Ozdemir, Sadin; Mohamedsaid, Siham Abdullah; Kilinc, Ersin; Yildirim, Aydil; Soylak, Mustafa
    Pleurolus eryngii loaded Fe2O3 magnetic nanoparticles were developed as novel magnetic solid phase bio-extractors for the preconcentrations and extractions of Co(II) and Hg(II) from real samples. The metal binding surface groups of the prepared magnetic solid phase bio-extractors were investigated by FT-IR spectrometry, SEM and EDX. Several parameters influencing the magnetic extractions and preconcentrations of Co(II) and Hg (II) were examined and optimized, including pH, flow rate, quantity of P. eryngii, quantity of Fe2O3 magnetic nanoparticle, eluent type, concentration and volume, sample volume, and foreign ions. A good reusage (35 times) was obtained with the relative standard deviation (RSD) of < 5.0% for both magnetic solid phase bio-extractors. The biosorption capacities were determined for Co(II) and Hg(II) as 25.4 mg g(-1) and 30.3 mg g(-1), respectively, using P. eryngii loaded Fe2O3 magnetic nanoparticle column. The preconcentration factors for Co(II) and Hg(II) were found as 80 and 100, respectively, when using P. eryngii loaded Fe2O3 magnetic nanoparticle column. The developed procedures were validated through analysis of the certified reference materials and successfully utilized for the determinations of Co(II) and Hg(II) in real samples by inductively coupled plasma optical emission spectrometry (ICP-OES) with satisfactory results.
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    Bacillus sp immobilized on Amberlite XAD-4 resin as a biosorbent for solid phase extraction of thorium prior to UV-vis spectrometry determination
    (Springer Wien, 2010) Ozdemir, Sadin; Erdogan, Sait; Kilinc, Ersin
    A method has been developed for the preconcentration of Th prior to its determination by UV-vis spectrophotometry after complexation with Arsenazo Ill. A column was packed with Amber lite XAD-4 resin containing immobilized Bacillus sp. as a solid phase extractant. Parameters such as pH of the solution and sample, the concentration of Th, the volume and type of eluent, flow rate and effect of matrix interference were studied. The optimum pH for the sorption of Th is 5.0, and quantitative eluation occurs with 1 mol L-1 HCl. The tolerance limits of some electrolytes were also studied. The loading capacity was determined to be 17.2 mg g(-1) The method was applied to the determination of Th in real ore sample and validated by analyzing a certified reference samples (NCS DC-73350; poplar leaves).
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    Bioaccumulation, tolerance, and removal of U(VI) and Th(IV) by a novel thermophilic Bacillus cereus ST14 isolated from hot spring mud samples in Afyonkarahisar, Turkey
    (Springer Heidelberg, 2024) Ozdemir, Sadin; Acer, Omer; Kilinc, Ersin
    In this study, a novel thermophilic Bacillus cereus ST14 with heavy metal tolerance was isolated from a hot spring mud sample in Afyonkarahisar (Omer). 16S rRNA analysis revealed that strain ST14 was mostly related to Bacillus cereus strain 151,007-R3_K09_40_27F (98.18%) and Bacillus cereus strain 2 k (98.10%). We hypothesized that U(VI) and Th(IV) affected B. cereus at the cell level and that this bacterium can be used as a bioindicator. Therefore, U(VI) and Th(IV) tolerance, removal, bioaccumulation, and impacts on antioxidant enzymes of thermophilic B. cereus have been examined in detail. Changes in the surface macrostructure and functionality of B. cereus following interaction with U(VI) and Th(IV) were studied using a scanning electron microscope and fourier transform infrared spectroscopy. B. cereus was found to be highly resistant to 10 and 12.5 mg/L of U(VI) and Th(IV) after 24-h incubation. Superoxide dismutase (SOD) and catalase (CAT) activities were observed to be increased by different U(VI) and Th(IV) concentrations. The highest bioaccumulation capacity quantities were detected as 100.79 and 87.96 mg metal/g dried bacteria at 24th h at 12.5 mg/L concentration for U(VI) and Th(IV), respectively. The highest U(VI) and Th(IV) cell membrane bioaccumulation capabilities of B. cereus have been measured as 318.94 and 263.89 mg metal/g wet membrane, respectively, at 24 h and 12.5 mg/L. This study's findings suggested that B. cereus could be employed as a bioindicator organism for detecting metal contamination in natural or industrial water samples. However, further research should focus on other thermophilic microorganisms.
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    Biosorption of Cd, Cu, Ni, Mn and Zn from aqueous solutions by thermophilic bacteria, Geobacillus toebii sub.sp decanicus and Geobacillus thermoleovorans sub.sp stromboliensis: Equilibrium, kinetic and thermodynamic studies
    (Elsevier Science Sa, 2009) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara; Guven, Kemal
    Biosorption of each of the ions Cd2+, Cu2+, Ni2+, Zn2+ and Mn2+ on Geobacillus toebii sub.sp. decanicus (G1) and Geobacillus thermoleovorans sub.sp. stromboliensis (G2) in a batch stirred system was investigated. The equilibrium adsorptive quantity was determined to be a function of the solution pH, contact time, biomass concentration, initial metal concentrations and temperature. The results obtained from biosorption experiments are used to understand the driving forces that govern the interaction between metal ions and a biosorbent. The experimental results were fitted well to the Scatchard plot, Langmuir, Freundlich, Dubinin-Radushkevich (D-R) isotherms. According to the parameters of the Langmuir isotherms, the maximum biosorption capacities of Cd2+, Cu2+, Ni2+, Zn2+ and Mn2+ for G2 were 38.8, 41.5, 42, 29 and 23.2 mg/g, respectively, while 29.2, 48.5, 21, 21.1 and 13.9 mg/g for G1, respectively. The mean free energy values evaluated from the D-R model indicated that the biosorptions of studied heavy metal ions onto bacteria were taken place by physical interaction. The biosorption mechanisms of studied metal ions on to the biosorbents were analysed by FT-IR spectra of G1 and G2 with and without metal ions. The first order and second order coefficients were obtained at 298, 308, 318 and 343 K. The experimental results were used to calculate the thermodynamic parameters. (C) 2009 Elsevier B.V. All rights reserved.
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    Biosorption of Heavy Metals (Cd2+, Cu2+, Co2+, and Mn2+) by Thermophilic Bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus: Equilibrium and Kinetic Studies
    (Taylor & Francis Inc, 2013) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara
    Two strains of thermophilic bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus, were employed to investigate the biosorption of heavy metals including Cd2+, Cu2+, Co2+, and Mn2+ ions. The effects of different biosorption parameters such as pH (2.010.0), initial metal concentrations (10.0300.0mg L-1), amount of biomass (0.2510g L-1), temperature (3080 degrees C), and contact time (15120min) were investigated. Concentrations of metal ions were determined by using an inductively coupled plasma optical emission spectrometry (ICP-OES). Optimum pHs for Cd2+, Cu2+, Co2+, and Mn2+ biosorption by Geobacillus thermantarcticus were found to be 4.0, 4.0, 5.0, and 6.0, respectively. For Anoxybacillus amylolyticus, the optimum pHs for Cd2+, Cu2+, Co2+, and Mn2+ biosorption were found to be 5.0, 4.0, 5.0, and 6.0, respectively. The Cd2+, Cu2+, Co2+, and Mn2+ removals at 50mg L-1 in 60min by 50mg dried cells of Geobacillus thermantarcticus were 85.4%, 46.3%, 43.6%, and 65.1%, respectively, whereas 74.1%, 39.8%, 35.1%, and 36.6%, respectively, for Anoxybacillus amylolyticus. The optimum temperatures for heavy metal biosorption were near the optimum growth temperatures for both strains. Scatchard plot analysis was employed to obtain more compact information about the interaction between metal ions and biosorbents. The plot results were further studied to determine if they fit Langmuir and Freundlich models.
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    Cd, Cu, Ni, Mn and Zn resistance and bioaccumulation by thermophilic bacteria, Geobacillus toebii subsp decanicus and Geobacillus thermoleovorans subsp stromboliensis
    (Springer, 2012) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara; Guven, Kemal
    Bioaccumulation and heavy metal resistance of Cd2+, Cu2+, Ni2+, Zn2+ and Mn2+ ions by thermophilic Geobacillus toebii subsp. decanicus and Geobacillus thermoleovorans subsp. stromboliensis were investigated. The metal resistance from the most resistant to the most sensitive was found as Mn > Ni > Cu > Zn > Cd for both Geobacillus thermoleovorans subsp. stromboliensis and Geobacillus toebii subsp. decanicus. It was determined that the highest metal bioaccumulation was performed by Geobacillus toebii subsp. decanicus for Zn (36,496 mu g/g dry weight cell), and the lowest metal bioaccumulation was performed by Geobacillus toebii subsp. decanicus for Ni (660.3 mu g/g dry weight cell). Moreover, the dead cells were found to biosorbe more metal in their membranes compared to the live cells. In the presence of 7.32 mg/l Cd concentration, the levels of Cd absorbed in live and dead cell membranes were found as 17.44 and 46.2 mg/g membrane, respectively.
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    Comparison of Cd(II) preconcentrations by using magnetized Pleurotus erygnii and Coprinus micaceus and its determination in real samples
    (Elsevier Science Bv, 2019) Ozdemir, Sadin; Yalcin, M. Serkan; Kilinc, Ersin; Soylak, Mustafa
    The utilization of the magnetized Pleurotus erygnii and Coprinus micaceus with gamma-Fe2O3 nanoparticles as biosorbents for magnetic solid phase extraction (MSPE) of Cd(II) were investigated in details. The surface structures of magnetized P. erygnii and C. micaceus were investigated by the Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The best process conditions were tested and determined as pH 5, 3 mL min(-1) flow rate, 100 mg of P. erygnii and C. micaceus on 75 mg of gamma-Fe2O3 nanoparticles, 5 mL of 1 mol L-1 HCl as eluent, and 400 mL of sample volume for both biosorbents. The limit of detections (LOD) were achieved as 0.054 ng mL(-1) and 0.040 ng(-1) for magnetized P. erygnii and C. micaceus, respectively. Preconcentration factors were determined as 80 for both magnetized biosorbents. The recommended methods were validated using certificated reference materials. Cd(II) in different real samples were determined by ICP-OES (inductively coupled plasma optical emission spectrometry) after preconcentration with developed methods.
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    Fe3O4@SiO2@Bacillus pumilis: magnetised solid phase bio-extractor for preconcentration of Pb(II) and Cu(II) from water samples
    (Taylor & Francis Ltd, 2019) Erbas, Zeliha; Soylak, Mustafa; Ozdemir, Sadin; Kilinc, Ersin
    In this study, preconcentration and separation of Cu(II) and Pb(II) ions by using Fe3O4@SiO2@Bacillus pumilis before their determinations by flame atomic absorption spectrometry (FAAS) were investigated. The thermophilic Bacillus pumilis were isolated from Meyremderesi spring, Sirnak, Turkey. Effects of important parameters such as pH, adsorbent amount, eluent type, concentration and volume of eluent and sample volume on magnetic solid phase extraction (MSPE) were examined in details. The preconcentration factors for Cu(II) and Pb(II) ions were calculated as 30 and 40, respectively. The accuracy of the proposed extraction procedure was validated analysing certificated reference materials and addition - recovery tests. The concentration of copper and lead were determined in water samples from Turkey by Flame AAS after application developed preconcentration-separation method.
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    GENOTOXICITY OF ESSENTIAL OIL OF Thymbra spicata L. var spicata IN SALMONELLA/MICROSOME AND SOS CHROMOTEST
    (Parlar Scientific Publications (P S P), 2009) Tolan, Veysel; Kizil, Sueleyman; Ozdemir, Sadin; Demirci, Ozlem
    Essential oils are concentrated, hydrophobic liquid containing, volatile aroma compounds from plants, which are called aromatic herbs or aromatic plants. Various essential oils and their monoterpenoid constituents have been widely used as fragrances in cosmetics, as flavouring food additives. and as scenting agents in a variety of household products. The present study was undertaken to investigate the mutagenic potential of essential oil of Thymbra spicata L. var spicata by Sahnonella/microsome assay TA98 and TA 100 tester strains, and also SOS chromotest with E.coli PQ37 strain, with and without addition of an S9 metabolic activation mixture. The essential oil of T spicata L. var spicata showed weakly mutagenic activity on both strains of Salmonella either without or with S9 mixture. No mutagenicity was found in the SOS chromotest either with or without S9 mixture. These results indicate a weak mutagenicity of the essential oil of Thymbra spicata in vitro.
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    Geobacillus thermoleovorans immobilized on Amberlite XAD-4 resin as a biosorbent for solid phase extraction of uranium (VI) prior to its spectrophotometric determination
    (Springer Wien, 2012) Ozdemir, Sadin; Kilinc, Ersin
    Geobacillus thermoleovorans subsp stromboliensis, was immobilized on an Amberlite XAD-4 ion exchanger and used as a solid phase extractant for the preconcentration of U(VI) ions prior to their determination by UV-VIS spectrophotometry. Parameters affecting the preconcentration (such as the pH value of the sample solution, the concentration of U(VI), the volume and type of eluent, the flow rate and the effect of potentially interfering ions) were studied. The optimum pH for the sorption of U(VI) was found to be pH 5.0. 5.0 mL of 1 M hydrochloric acid were used to eluate the U(VI) from the column. The loading capacity is 11 mg g(-1). The limits of detection and quantification are 2.7 and 9.0 mu g L-1, respectively, and relative standard deviations are < 10 %. The method was applied to the determination of U(VI) in a certified reference sample (NCS ZC-73014; tea leaves) and in natural water samples.
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    Isolation of a thermophilic Anoxybacillus flavithermus sp nov and production of thermostable ?-amylase under solid-state fermentation (SSF)
    (Bmc, 2012) Ozdemir, Sadin; Matpan, Fatma; Okumus, Veysi; Dundar, Abdurrahman; Ulutas, Mehmet Sefa; Kumru, Mert
    A new bacteria was isolated from hot-spring water of Gazligol, Afyonkarahisar in Turkey. Based on morphological and biochemical tests and 16S rRNA gene sequence analysis, the isolate belonged to the Anoxybacillus flavithermus species which has 99% similarity with the bacterium DNA. The production of alpha-amylase by thermophilic Anoxybacillus flavithermus was investigated under solid-state fermentation by using some agricultural waste as substrates. Solid substrates such as rice husk, banana husk, millet, water melon husk, lentil bran, wheat bran and maize oil cake were studied for enzyme production. Of these, rice husk was proved as the best substrate for alpha-amylase production (1,271 U/mg). The maximum alpha-amylase production was observed as 1,803 U/mg at 72 h, 1,000 mu m particle size, 70% initial moisture content (w/v), and 40% inoculum level (v/w). Among the various nitrogen sources tested, 1% peptone (3,170 U/mg) was found to be the best nitrogen source for alpha-amylase production. As additional carbon sources, 1% starch (2,364 U/mg) enhanced alpha-amylase production. The optimum temperature for the activity of alpha-amylase was found to be 70A degrees C. The enzyme was optimally active at pH 6.0 and stable in the pH range of 6.0-8.0.
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    A magnetized fungal solid-phase extractor for the preconcentrations of uranium(VI) and thorium(IV) before their quantitation by ICP-OES
    (Springer Wien, 2019) Kilinc, Ersin; Ozdemir, Sadin; Yalcin, M. Serkan; Soylak, Mustafa
    The fungus Bovista plumbea immobilized on -Fe2O3 nanoparticles is shown to be a novel sorbent for magnetic solid-phase extractions of U(VI) and Th(IV). The biosorbent was characterized by FT-IR, SEM, and EDX. The effects of pH value, flow rate and volumeof sample, amounts of biomass and support material, eluent type, foreign ions and repeated use of the sorbent on extraction efficiency were investigated. The sorption capacities are 41 and 44mgg(-1), respectively, for U(VI) and Th(IV). The results indicated that B. plumbea immobilized onto -Fe2O3 nanoparticles can be utilized as a novel material for the preconcentrations of U(VI) and Th(IV) in certified materials and in spiked tap, river and lake waters.
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    Mutagenicity of Hypericum lysimachioides extracts
    (Taylor & Francis Inc, 2009) Tolan, Veysel; Toker, Zuhal; Ozdemir, Sadin; Demirci, Oezlem; Otludil, Birol; Oezen, Hasan C.
    Hypericum (Hypericaceae) species are extensively used in several fields such as traditional medicine, food and crop protection. Despite its usage in many fields, the identification of the genotoxic potential of this herb is still incomplete. In this study, we evaluated genotoxic effects of the petroleum ether, hexane, ethyl acetate, and methanol extract of Hypericum lysimachioides Boiss. var. lysimachioides by Ames Salmonella/microsome test and SOS chromotest. The mutagenic activity of Hypericum lysimachioides var. lysimachioides extracts was investigated by using Salmonella typhimurium strains TA98 and TA 100 and also the SOS chromotest with Escherichia coli PQ37 strain, with or without S9 metabolic activation. In this initial report we demonstrated that all extracts of H. lysimachioides var. lysimachioides showed significant mutagenic activity on both strains of Salmonella either with or without S9 mixture. No mutagenicity was found in the SOS chromotest either with or without S9 mixture. These results indicate a significant mutagenicity of the petroleum ether, hexane, ethyl acetate and methanol extracts of Hypericum lysimachioides var. lysimachioides in vitro. It can be suggested that quercetin and flavonol or their synergistic effects may be main mutagenic agents in the photopharmaceuticals Hypericum lysimachioides var. lysimachioides extract.
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    A new magnetized thermophilic bacteria to preconcentrate uranium and thorium from environmental samples through magnetic solid-phase extraction
    (Elsevier, 2020) Ozdemir, Sadin; Kilinc, Ersin; Yalcin, Mustafa Serkan; Soylak, Mustafa; Sen, Fatih
    A magnetic solid-phase extraction (MSPE) method was developed for simultaneous preconcentrations of U(VI) and Th(IV) before their measurements by inductively coupled plasma optical emission spectrometry (ICP-OES). The main idea of this biotechnological application depends on the use of bacteria, thermophilic Bacillus cereus SO-14, as a solid-phase biosorbent. It was immobilized to gamma-Fe2O3 magnetic nanoparticles and used for MSPE. Characterization of the biosorbent was performed using the scanning electron microscope (SEM), the energy dispersive X-ray (EDX) and Fourier transform infrared (FT-IR) spectroscopy. Also, the the best conditions of experimental parameters were examined, and the reliability of the method developed was verified by applying the certified reference materials. Limit of detections (LODs) of the U(VI) and Th(IV) was calculated as 0.008 and 0.013 ng mL(-1) respectively. Relative standard deviations (RSDs) were found to be 1.6 and 2.4 %, respectively, for U(VI) and Th(IV). R-2 was also calculated as 0.9991. Preconcentration factors were achieved as 100 for both elements. It should be highlighted that LODs were critically improved and the sensitivity of ICP-OES was enhanced. (C) 2020 Elsevier B.V. All rights reserved.
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    A new method for preconcentration of Th(IV) and Ce(III) by thermophilic Anoxybacillus flavithermus immobilized on Amberlite XAD-16 resin as a novel biosorbent
    (Elsevier Science Bv, 2017) Yener, Ismail; Oral, Elif Varhan; Dolak, Ibrahim; Ozdemir, Sadin; Ziyadanogullari, Recep
    A novel approach has been improved for the preconcentration of Th(IV) and Ce(III) by using thermophilic Anoxybacillus flavithermus which were immobilized on Amberlite XAD-16 resin and analyzed by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The concentration of Th(IV) and Ce(III), the eluent type and volume, the pH of model solutions, influences of matrix interference parameters, and flow rate were analyzed and optimized extraction conditions were determined. The optimum pH for quantitative sorption of Th(IV) and Ce(III) was found as 7.0 and elution of Th(IV) and Ce(III) from mini-columns was studied with 1.0 mol L-1, 5 mL HNO3 with recoveries from 100%. The precision of this method was validated by comparing the analytical recovery and certified reference materials (IAEA Soil-7). Finally, this enrichment method was used to determine Th(IV) and Ce(III) in bastnaesite ore sample. (C) 2017 Elsevier B.V. All rights reserved.
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    A new method for the preconcentrations of U(VI) and Th(IV) by magnetized thermophilic bacteria as a novel biosorbent
    (Springer Heidelberg, 2021) Kilinc, Ersin; Ozdemir, Sadin; Yalcin, M. Serkan; Soylak, Mustafa
    This paper proposes the use of Anoxybacillus flavithermus SO-15 immobilized on iron oxide nanoparticles (NPs) as a novel magnetized biosorbent for the preconcentrations of uranium (U) and thorium (Th). The SPE procedure was based on biosorption of U(VI) and Th(IV) on a column of iron oxide NPs loaded with dead and dried thermophilic bacterial biomass prior to U(VI) and Th(IV) measurements by ICP-OES. The biosorbent characteristicswere explored using FT-IR, SEM, and EDX. Significant operational factors such as solution pH, volume and flow rate of the sample solution, amounts of dead bacteria and iron oxide nanoparticles, matrix interference effect, eluent type, and repeating use of the biosorbent on process yield were studied. The biosorption capacities were found as 62.7 and 56.4 mg g(-1) for U(VI) and Th(IV), respectively. The novel extraction process has been successfullyapplied to the tap, river, and lake water samples for preconcentrations of U(VI) and Th(IV).
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    Phallus impudicus loaded with ?-Fe2O3 as solid phase bioextractor for the preconcentrations of Zn(II) and Cr(III) from water and food samples
    (Elsevier Sci Ltd, 2020) Yalcin, M. Serkan; Kilinc, Ersin; Ozdemir, Sadin; Yuksel, Uyan; Soylak, Mustafa
    We investigated the application of fungus Phallus impudicus loaded gamma-Fe2O3 nanoparticles as a biosorbent for magnetic solid phase extractions of trace levels of Zn(II) and Cr(III) ions from natural samples before their measurements by inductively coupled plasma optical emission spectrometry. The characterization of magnetized P. impudicus was performed using the scanning electron microscope, the energy dispersive X-ray and Fourier transform infrared spectroscopy. Important experimental factors were investigated. The experimental results fitted well to the Langmuir adsorption model and pseudo-second order kinetic model. Limit of detections of targeted ions by magnetic solid phase extraction method based on use of P. impudicus were found as 10.5 ngL(-1) and 12.6 ngL(-1) respectively for Cr(III) and Zn(II). The sorption capacities of the biosorbent were 22.8 mgg(-1) for Cr(III) and 25.6 mgg(-1) for Zn(II). The preconcentration factors were achieved as 100 for both of ions. RSDs for inter- and intraday precisions were found as lower than 2.0% and 2.1% respectively for both of targeted ions. The accuracy of the recommended process was tested by recovery measurements on the certificated reference materials and successfully applied for quantification recoveries of Cr(III) and Zn(II) ions from water and food samples.