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Objectives The purpose of the study was to prepare an effective and new drug delivery system for enhancing the stability of Phenethyl isothiocyanate (PEITC), and its hepatoprotective effect in the carbon tetrachloride (CCl4)-induced damage in hepatocellular carcinoma G2 (HepG2) cell line via nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway. Methods Gold nanoparticles were synthesized and then characterized by XRD, SEM, SEM-EDX analysis, hydrodynamic diameter and zeta potential measurements. 1.0024 mM PEITC, a naturally occurring isothiocyanate, an active ingredient was loaded onto the characterized AuNPs. The cytotoxicity test of PEITC-AuNP and effects on ALT, AST, Nrf2 levels and total antioxidant capacity (TAC) of CCI4-induced HepG2 cells were investigated. Results PEITC-AuNPs and PEITC decreased ALT and AST levels (p0.05). PEITC didn’t increase the Nrf2 level in CCI4-induced HepG2 cells. TAC of both PEITC-AuNPs and PEITC administration increased significantly compared with CCl4 group (p Conclusions PEITC-AuNPs were more effective than PEITC which resulted in more hepatoprotective and antioxidant effects via Nrf2 activation against CCl4-induced liver injury in HepG2 cells.

In this study, toxic effects caused by the degradation of fluoxastrobin, which is a commonly used fungicide where newly synthesized manganese or sulfur-doped TiO2 nanoparticles exist were evaluated. The characterization study of nanoparticles was performed by scanning an electron microscopy (SEM), X-ray diffractometry, Brunau-Emmet-Teller analysis, X-ray fluorescence spectroscopy, and UV-Vis (ultraviolet-visible) reflectance spectra. Subsequently, the photocatalytic performance of nanoparticles, their toxicity, and the photocatalytic degradation products of fluoxastrobin with the same nanoparticles were tested during the two development stages of Xenopus laevis. The LC(50)s of fluoxastrobin were determined on test organisms, and a 5 mg L-1 fluoxastrobin was selected to evaluate the photocatalytic degradation capacity due to toxicity studies. The sublethal effects of the nanoparticles and the degradation product of fluoxastrobin were assessed with embryonic malformations and biochemical marker responses. Sulfur-doped TiO2 was found to be more effective compared to manganese-doped TiO2 for the degradation of fluoxastrobin, photocatalytically. On the other hand, even if the tested nanoparticles were not lethal, they caused effects such as growth retardation and changes in biochemical responses on organisms.

The use of TiO2-based samples with nanotube (NT) shape for humidity sensing has been investigated. Sample characterization was carried out using x-ray diffraction analysis, scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy. x-Ray diffraction analysis showed that the nanotubes had TiO2, NaO3, and H2Ti2O5 phases. SEM revealed that the NTs had diameters ranging from 20 nm to 200 nm and very different lengths. TiO2-based nanotubes were coated using the drop-casting method onto a quartz crystal microbalance (QCM). The synthesis of TiO2-based NTs was performed using a hydrothermal process. Humidity sensing measurements showed that the resonant frequency of TiO2-based NTs deposited onto the QCM was very sensitive to humidity changes. It was also shown that the sensor could be used for respiratory monitoring purposes.

Photocatalytic degradation of Amoxicillin (AMX) in aqueous solution by Co-doped TiO2 and undoped TiO2 synthesized by reflux route was investigated. The catalysts were characterized using X-ray diff...

Photocatalytic degradation of Ibuprofen (IBU) which is an anti-inflammatory drug was investigated in aqueous solution by Co-doped TiO2 and bare TiO2 synthesized by reflux route. The prepared catalyst powders were fully characterized using X-ray diffraction (XRD), FT-IR spectroscopy, scanning electron microscopy (SEM), BET surface areas, X-ray Fluorescence Spectroscopy (XRF), dynamic light scattering (DLS). Efficiency of photocatalytic activity for synthesized Co-doped and bare TiO2 was evaluated for the degradation of IBU under UV-C and visible irradiation by investigating the effects of cobalt doping percentage, amount of catalyst, irradiation time, initial IBU concentration, pH and also the effect of organic and inorganic matrix. At optimum degradation conditions under UV-C light and visible light, photocatalytic degradation rates were monitored using UV/Vis spectrophotometer, HPLC and Total Organic Carbon (TOC) analysis. The results showed up the degradation of IBU was improved upon Co doping. It was detected that complete removal was achieved within 240 min of irradiation under UV-C and 98% of IBU was decomposed under visible light in 300 min.

Madimak (Polygonum cognatum Meissn.) plant is a wild edible plant with a cosmopolitan distribution and also traditionally consumed as food in anatolia. This study aims to optimize the extraction parameters in the pressurized liquid extraction (PLE) system and to search some beneficial properties of this plant. After the optimal extraction conditions was determined, the effect of PLE conditions on antioxidant properties was studied by using plant extracts in terms of total phenolic contents, free radical scavenging capacities and reducing power. A solvent including 1 M NaOH and water (1:99), 60 min of extraction time, 40 oC of extraction temperature and 1500 psi of pressure were optimized and found as the most productive operating conditions for PLE in the folic acid determination. Mainly, optimization of PLE conditions were carried out by considering folic acid amounts. Although antioxidant activity levels differ depending on solvent components, the similar results were obtained such in the other optimization parameters.

Madimak (Polygonum cognatumMeissn.) plant is a wild edible plant with a cosmopolitan distribution andalso traditionally consumed as food in anatolia. This study aims to optimizethe extraction parameters in the pressurized liquid extraction (PLE) system andto search some beneficial properties of this plant. After the optimal extraction conditions wasdetermined, the effect of PLE conditions on antioxidant properties was studiedby using plant extracts in terms of total phenolic contents, free radicalscavenging capacities and reducing power. A solvent including 1 M NaOH andwater (1:99), 60 min of extraction time, 40 oC of extractiontemperature and 1500 psi of pressure were optimized and found as the mostproductive operating conditions for PLE in the folic acid determination.Mainly, optimization of PLE conditions were carried out by considering folicacid amounts. Although antioxidant activity levels differ depending on solventcomponents, the similar results were obtained such in the other optimizationparameters., Madımak (Polygonum cognatum Meissn) bitkisi geleneksel olarak Anadolu’dagıda olarak tüketilen, kozmopolitan bir dağılıma sahip kendiliğinden yetişenbirbitkidir. Bu çalışma temelde bu bitkinin yararlı özelliklerini ortaya çıkarmakadına basınçlı sıvı ekstraksiyon sisteminin optimizasyonunu amaçlar. Optimalkoşullar belirlendikten sonra, ekstraksiyon koşullarının antioksidan özelliklerüzerine etkisi, toplam fenolik içerik, serbest radikal süpürücü etki veindirgeme gücü özelinde değerlendirildi. İdeal optimizasyon koşullarının 1 MNaOH ve suyun (1:99) çözegen karışımı ile, 60 dk boyunca , 40 oCsıcalıkta, 1500 psi basınçta folik asit için en ideal olduğu belirlendi.Temelde, antioksidan aktivite için gerekli koşullar folik asit için yapılanoptmizasyonlar dikkate alınarak belirlenmiştir. Elde edilen sonuçlara göreantioksidan aktivite seviyelerinin çözücü bileşiminden etkilendiği aynı şekildediğer optimizasyon parametrelerin de değişkenlik gösterdiği gözlenmiştir.

The toxic effects of two selected xenobiotics, bisphenol A (BPA) and atrazine (ATZ), were evaluated after photocatalytic degradation using nano-sized, Mn-doped TiO2. Undoped and Mn-doped TiO2 nanoparticles were synthesized. The samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), UV-vis-diffuse reflectance spectra (DRS), X-ray fluorescence spectroscopy (XRF), and BET surface area. The photocatalytic efficiency of the undoped and Mn-doped TiO2 was evaluated for BPA and ATZ. The toxicity of the synthesized photocatalysts and photocatalytic by-products of BPA and ATZ was determined using frog embryos and tadpoles, zebrafish embryos, and bioluminescent bacteria. Possible toxic effects were also evaluated using selected enzyme biomarkers. The results showed that Mn-doped TiO2 nanoparticles did not cause significant lethality in Xenopus laevis embryos and tadpoles, but nonfiltered samples caused lethality in zebrafish. Furthermore, Mn-doping of TiO2 increased the photocatalytic degradation capability of nanoparticles, and it successfully degraded BPA and AZT, but degradation of AZT caused an increase of the lethal effects on both tadpoles and fish embryos. Degradation of BPA caused a significant reduction of lethal effects, especially after 2-4 h of degradation. However, biochemical assays showed that both Mn-doped TiO2 and the degradation by-products caused a significant change of selected biomarkers on X. laevis tadpoles; thus, the ecological risks of Mn-doped TiO2 should be considered due to nanomaterial applications and for spilled nanoparticles in an aquatic ecosystem. Also, the risk of nanoparticles should be considered using indicator reference biochemical markers to verify the environmental health impacts. (C) 2015 Elsevier B.V. All rights reserved.

In this study, TiO2 nanotubes (TiO2-NTs) are coated with a drop-casting method on Fe40Ni38Mo4B18 amorphous ferromagnetic ribbons and the humidity response of the prepared magnetoelastic sensors (MES) is investigated. The synthesis of TiO2-NTs is performed using a hydrothermal process. Sample characterization is carried out using X-ray diffraction and scanning electron microscopy. The results show that the sensors can measure moisture values in the range of 5% to 95% with very high precision and very low hysteresis. The humidity variation between 5% and 95% shows a change in the sensor resonance frequency of ~3180 Hz, which is a significant change compared to many magnetoelastic humidity sensors developed so far.

An analytical procedure was proposed to study the operational fraction of Cu in ripe-fresh, sun-dried and sulphited-dried apricots harvested from either treated Bordeaux mixture or unexposed trees. Based on the methods that consists pressurized liquid extraction procedure and solid phase extraction to separate diverse Cu fractions on different sorbents such as Dowex 50Wx8-40 and Amberlite XAD-7, and then flame atomic absorption spectrometry (FAAS) and ion selective electrode were used for off-line determination of Cu concentrations in the effluents obtained.Total copper concentrations in different processing the apricot samples exposed to Bordeaux mixture were 4.58, 4.48 and 4.25 μg/g in ripe fresh, sun-dried, sulphuring-sun drying, respectively. However, Cu concentrations in the organic apricot samples were determined 2.92; 2.97 and 2.25 μg/g. While circa 40-59% of total copper are extractable with water solvent including about 67-68% cationic copper, 25-33% organically bound copper and 26- 44% labile in Kabaasi apricot samples. Besides, while about 27-48% of total copper are extractable with methanol: water solvents containing about 40-23% cationic copper, 60-78% organically bound copper and 56-71% of copper was absorbed in the stomach.It was applied to analytical procedures for Cu speciation in the apricot samples were verified and validated.

Photocatalytic performance of a hydrothermally synthesized pure anatase TiO 2 with 8 nm average crystallite size for decomposition of Reactive Red 141 was examined by investigating the effects of UV-light irradiation time, irradiation power, amount of TiO 2 and initial dye concentration. Change in the UV absorbance of the dye during irradiation was monitored. One wt.% TiO 2 in 30 mg/l Reactive Red 141 aqueous solution was found adequate for complete decolorization in 70 min at 770 W/m 2 irradiation power. It was realized that, compared to Degussa P-25, the synthesized nano-TiO 2 can be repeatedly used as a new catalyst. The results also proved that Reactive Red 141 is decomposed catalytically due to the pseudo first-order reaction kinetics.

Transparent nanocrystalline pure anatase titania (nano-TiO 2 ) was synthesized by hydrothermal process at 200 °C. Photocatalytic activity of the nano-TiO 2 as in the form of sol was tested for degradation of Methylene Blue (MB) and Reactive Red 120 (RR-120) in aqueous solutions. Structural and physico-chemical properties of the nano-TiO 2 were characterized using powder XRD, SEM, BET, FT-IR and elemental analyses. Complete photodegradation of RR-120 was successfully achieved by aid of the nano-TiO 2 whereas MB was not degraded, maybe because of reversible color change in nano-TiO 2 sol/MB mixture after the UV irradiation was stopped. Potocatalytic activity of the synthesized the nano-TiO 2 for degradation of RR-120 was compared with Degussa P-25 at optimum conditions determined for RR-120. It was found that the nano-TiO 2 can be repeatedly used with higher photocatalytic activity than Degussa P-25.

Biosorption is an innovative and alternative technology to remove heavy metal pollutants from aqueous solution using live, inactive and dead biomasses such as algae, bacteria and fungi. In this study, live and dried biomass of Phanerochaete chrysosporium and Funalia trogii was applied as heavy metal adsorbent material. Biosorption of copper(II) cations in aqueous solution by live and dried biomass of Phanerochaete chrysosporium and Funalia trogii was investigated to study the effects of initial heavy metal concentration, pH, temperature, contact time, agitation rate and amount of fungus. Copper(II) was taken up quickly by fungal biomass (live or dried) during the first 15 min and the most important factor which affected the copper adsorption by live and dried biomass was the pH value. An initial pH of around 5.0 allowed for an optimum adsorption performance. Live biomass of two white rot fungi showed a high copper adsorption capacity compared with dried biomass. Copper(II) uptake was found to be independent of temperature in the range of 20-45 °C. The initial metal ion concentration (10-300 mg/L) significantly influenced the biosorption capacity of these fungi. The results indicate that a biosorption as high as 40-60 % by live and dried biomass can be obtained under optimum conditions.

Hydrolysis product of alcohol modified titanium(IV)‐n‐propoxide and its coated form were prepared as new and regenerable adsorbents for adsorbing and removing Cu(II) ions from its different aqueous solutions. The hydrolysis and alcoholysis products and adsorbents were characterized using GC, 1H‐NMR, FT‐IR, SEM, and TG‐DTA analysis. It was found that Cu(II) ion adsorption rather increased when hydrolysis product of alcohol modified titanium(IV)‐n‐propoxide was coated with prehydrolyzed 3‐mercaptopropyltrimethoxy silane in n‐propanol and this coated material was used as adsorbent. Depending on the results of experiments performed at optimum conditions of initial Cu(II) concentration, amount of adsorbent, contact time, and pH, maximum adsorption of Cu(II), i.e., >98% has been achieved under the non‐competitive conditions, while almost 60% is achieved under the competitive conditions of Pb(II), Zn(II), Fe(III), and alkali and earth alkali metals. It was also concluded that Cu(II) adsorption efficienc...

Fe, Zn, Mn and Cu levels in three Turkish legumes, kidney bean (Phaseolus vulgaris L.), lentil (Lens esculenta) and chickpea (Cicer arietinum), were determined by flame atomic absorption spectrometry. Dissolution conditions in the microwave-assisted wet digestion method were studied by investigating several variables, including type of acid mixture, acid volume, digestion time, microwave power input and sample weight. Comparison with conventional wet acid digestion was also made. In order to check the element losses during digestion and the accuracy of the results, all tests were repeated after the addition of a spiked standard element solution to the legume sample. The microwave-assisted digestion procedure optimised for kidney bean was adapted for lentil and chickpea. Fe, Zn, Mn and Cu concentrations (mg per 100 g sample) were determined in kidney bean as 6.27 ± 0.94, 2.23 ± 0.36, 1.64 ± 0.14 and 0.99 ± 0.19, in lentil as 8.24 ± 1.11, 2.46 ± 0.06, 1.17 ± 0.19 and 1.01 ± 0.28 and in chickpea as 6.00 ± 1.40, 2.21 ± 0.14, 1.60 ± 0.43 and 0.58 ± 0.18 respectively. Copyright © 2005 Society of Chemical Industry

Surface modification of clay minerals has become increasingly important for improving the practical applications of clays such as fillers and adsorbents. In this study, the surface of pyrophyllite mineral was modified by coating with 3-(2-aminoethylamino) propyl-methyldimethoxysilane (APMDS) coupling agent and utility of the APMDS-modified pyrophyllite was investigated as an adsorbent for removal of Pb(II) ions from aqueous solutions. XRD, FT-IR and SEM analysis were used to characterise the surface modification and it was suggested that hydrogen bonding takes place between the hydroxyl groups and/or oxygen atoms within the structure of pyrophyllite and hydroxyl groups of APMDS. The APMDS-modified pyrophyllite adsorbed approximately 93% of Pb(II) ions at an initial concentration of 20 mg/l, while natural pyrophyllite did only 35% under the same conditions. The adsorption of Pb(II) increased with increasing pH and reached a maximum value in the pH range 6.5–7. The effects of various factors on the adsorption, such as pH of the solution, contact time, amount of adsorbent and initial Pb(II) concentration, were studied. The adsorption isotherm has been determined and data have been analysed according to the Langmuir model and found to be favourable, i.e., the separation parameter is less than unity ( R L

Fluoride ievels of underground vvater show variations reiated to chemicai composition of contacted earth layers and atmospheric conditions of fail regions. In this study, underground vvater fluoride İevels were investigated in two separate geographicai environments where fluorite rocks are abundant in Malatya. The fluoride İevels of vvater in research districts were found dearty high than control vaiues, aithough being lovver than WHO standards. Key words: Fluoride, underground vvaters, geo-chemical environment, Yeraltı sularının florür içeriği temas ettiği katmanların kimyasal bileşimine ve yağış bölgelerinin atmosferik koşullarına bağlı olarak değişiklikler göstermektedir. Bu çalışmada Malatya Hinin jeo-kimyasal çevresinde florit kayaçları içeren iki bölgenin yeraltı sularının florür içeriği araştırılmıştır. Araştırma bölgesi sularındaki florür düzeyi, karşılaştırma amacıyla belirlenen kontrol bölgesi sularına oranla belirgin ölçüde yüksek bulunmuşsa da, WHO standartlarının altında kaldığı belirlenmiştir. Anahtar kelimeler: Florür, yeraltı suları, jeo-kimyasal çevre

Degradation of Congo Red (CR) dye in aqueous solutions was investigated by means of photocatalysis of TiO2 which was hydrothermally synthesized at 200 degrees C in 2 h, in anatase phase with 8 nm crystallite size. Efficiency of TiO2 in photocatalytic degradation under visible irradiation was studied by investigating the effects of amount of TiO2, irradiation time, initial CR concentration and pH. It was found that complete decolorization is achieved within 30 min of irradiation. Effects of nitrate and sulphate ions and humic acid on the degradation were also tested. The results were compared with Degussa P-25 TiO2 at the same degradation conditions. Degradation products were detected using LC-MS technique. The probable pathways for the formation of degradation products were proposed. International Bureau of Federal Ministry for Education and Research (JULICH 42.6) Firat University Scientific Research Projects Management Unit (AFP 2002/53)

In this study, an analytical method for indirect measurement of Al bound with tannin in tea infusion was studied. This method utilizes the ability of the tannins to precipitate with protein. Separation conditions were investigated using model solutions. This method is uncomplicated, inexpensive and suitable for real samples. About 34% of the total Al in brew extracted from commercially available teas was bound to condensed and hydrolyzable tannins.

Pure anatase-TiO2 nanoparticles with 8 nm average crystallite size was synthesized hydrothermally at 200 degrees C in 2 h. The structural and physico-chemical properties of nano-TiO2 were determined by powder XRD, FT-IR, BET and SEM analyses. The behavior of anatase nano-TiO2 in catalytic degradation of Rhodamine B (RB) dye in transparent nano-TiO2 sol under UV-light was examined as a function of irradiation power of UV-light, irradiation time, amount of nano-TiO2 and initial RB concentration in the sol. Rhodamine B was fully degraded with the catalysis of the nano-TiO2 in a short time as low as 60 min. Photocatalytic activity of the nano-TiO2 for degradation of RB was compared with Degussa P-25 at optimum catalysis conditions determined for the nano-TiO2. It was found that, when compared to Degussa P-25, the nano-TiO2 could be repeatedly used with increasing photocatalytic activity. It was found that the photodegradation obeys the pseudo first-order reaction kinetics with the rate constant of 0.0658 min(-1), and the half period t1/2 was 10.53 min.

The surface of naturally hydrophobic mineral pyrophyllite was modified to hydrophilic by treatment with prehydrolyzed N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (APEO) coupling agent to prepare a novel and effective adsorbent for the removal of 4-nitrophenol (4-NP) from aqueous solutions. XRD, FTIR, and SEM analyses were used to characterize the surface modification. It was found that after the grafting procedure, heat treatment at 110 degrees C results in condensation reaction between the OH groups of the APEO molecule and the hydroxyl groups and/or oxygen atoms on the pyrophyllite surface and the adsorption of 4-NP by APEO-modified pyrophyllite involves interactions between dissociated 4-NP molecules and protonated amine groups of APEO molecules attached to the mineral surface. Adsorption equilibrium data for 4-NP adsorption on APEO-treated and untreated pyrophyllite were most satisfactorily fitted using the Freundlich adsorption isotherm and adsorption capacity was found to be 0.268 mg/g for modified pyrophyllite whereas it was only 0.105 mg/g for untreated pyrophyllite.

Speciation of metallic compunds is important especially for their bioavailability. In this present study fluoride bound aluminium species were determined in tea infusion. Total aluminium was measured using name atomic absorption spectrometry (FAAS). Free fluoride and total fluoride were measured by fluoride selective ion electrode (FISE) with the assistance of TISAB buffer solution used for adjustment of pH and total ionic strength, and ALCOA buffer solution which decomposes all of the Al-fluoride complexes in solution. During the studies, the effects of pH and time on the formation of Al-F complexes and interference of some metal ions found in tea infusion such as Al3+, Mg2+, Fe2+, Fe3+ and Mn2+ on the concentration of free fluoride were investigated. The concentration of each Al-fluoride complexes in tea infusion were determined indirectly by calculation using pF-Mole Fraction Diagram. It was found that 1.13+/-0.15 mg l(-1) of 12.00+/-0.86 mg l(-1) total aluminium is fluoride bound aluminium, which means that approximately 10% of total aluminium in tea infusion is complexed with fluoride.

There is a need to develop innovative and alternative technologies that can remove toxic heavy metal pollutants from wastewater. In this study, two agricultural residues, cotton stalks and apricot seeds, were used to adsorb copper and lead in solutions. Sorption capacities of agricultural wastes were significantly affected by solution pH, adsorbent mass and adsorbent particle size. The adsorption efficiency of two agricultural waste was in the order cotton stalk > apricot seed and the agricultural wastes adsorbed metal ions in the order of Pb > Cu. Treatment of these metals with agricultural wastes reduced their toxic effects on P. aeruginosa. This reduction in toxic effect is important both in respect of environmental biotechnology and waste detoxification. This study has indicated that cotton stalk and apricot seed could be employed as low-cost alternatives in wastewater treatment for the removal of heavy metals.