Facile fabrication of Fe-TiO2 thin film and its photocatalytic activity

Fe3+-TiO2 (Fe-TiO2) thin films were successfully prepared using a "sandwich" approach. TiO2 NPs were doped with different Fe3+ content (0.05%, 0.1%, 0.2% molar ratio), and the modified TiO2 NPs were deposited on glass flat support by dip coating. Structural, morphological, optical, and photocatalytic properties of Fe-TiO2 thin films were studied. XPS spectra confirm the presence of Ti, Fe, O, and defective -OH groups at the material surface. The Fe 2p spectrum demonstrates the existence of Fe3+. SEM images indicate that the incorporation of Fe3+ deforms in some degree the homogeneity of the TiO2 system. Additionally, incorporation of Fe3+ ions to the network creates an impurity band near the VB due to the oxygen vacancies, resulting in the reduction of the effective optical band gap. Photocatalytic activity of fabricated thin films in the elimination of sulfamethoxazole (SMT) follows pseudo first-order kinetics. The highest SMT removal yields were achieved using the sample with 0.05%Fe. Additionally, the use of greater thicknesses improves the removal performance. However, material detachment limits the maximum usable value around 6 mu m. Finally, stability and reusability of catalysts were confirmed studying the photocatalytic activity over three cycles and evaluating that no Fe3+ leaching occurred.This research was supported by Ministerio de Economia y Competitividad (Project AGL2016-80507-R) and University of Cadiz (Project PR2018-048)

Some ozone advanced oxidation processes to improve the biological removal of selected pharmaceutical contaminants from urban wastewater

Removal of nine pharmaceutical compounds¿acetaminophen (AAF), antipyrine (ANT), caffeine (CAF), carbamazepine (CRB), diclofenac (DCF), hydrochlorothiazide (HCT), ketorolac (KET), metoprolol (MET) and sulfamethoxazole (SMX)¿spiked in a primary sedimentation effluent of a municipal wastewater has been studied with sequential aerobic biological and ozone advanced oxidation systems. Combinations of ozone, UVA black light and Fe(III) or Fe3O4 constituted the chemical systems. During the biological treatment (hydraulic residence time, HRT = 24 h), only AAF and CAF were completely eliminated,MET, SMX and HCT reached partial removal rates and the rest of compounds were completely refractory. With any ozone advanced oxidation process applied, the remaining pharmaceuticals disappear in less than 10 min. Fe3O4 or Fe(III) photocatalytic ozonation leads to 35% mineralization compared to 13% reached during ozonation alone after about 30-min reaction. Also, biodegradability of the treated wastewater increased 50% in the biological process plus another 150% after the ozonation processes. Both untreated and treated wastewater was non-toxic for Daphnia magna (D. magna) except when Fe(III) was used in photocatalytic ozonation. In this case, toxicity was likely due to the ferryoxalate formed in the process. Kinetic information on ozone processes reveals that pharmaceuticals at concentrations they have in urban wastewater are mainly removed through free radical oxidation.The authors thank the Spanish CICYT and Feder funds for the economic support through project CTQ2009/13459/C05/05. Also, Chemical Engineer A. Espejo thanks Gobierno de Extremadura for providing her a FPI grant.Espejo, A.; Aguinaco, A.; Amat Payá, AM.; Beltrán, FJ. (2014). Some ozone advanced oxidation processes to improve the biological removal of selected pharmaceutical contaminants from urban wastewater. 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Occurrence and fate of pharmaceuticals in wastewater treatment plants and rivers in Korea. Environmental Pollution, 158(5), 1938-1947. doi:10.1016/j.envpol.2009.10.036Sui, Q., Huang, J., Deng, S., Yu, G., & Fan, Q. (2010). Occurrence and removal of pharmaceuticals, caffeine and DEET in wastewater treatment plants of Beijing, China. Water Research, 44(2), 417-426. doi:10.1016/j.watres.2009.07.010Calza, P., Massolino, C., Monaco, G., Medana, C., & Baiocchi, C. (2008). Study of the photolytic and photocatalytic transformation of amiloride in water. Journal of Pharmaceutical and Biomedical Analysis, 48(2), 315-320. doi:10.1016/j.jpba.2008.01.014Camacho-Muñoz, D., Martín, J., Santos, J. L., Aparicio, I., & Alonso, E. (2010). Occurrence, temporal evolution and risk assessment of pharmaceutically active compounds in Doñana Park (Spain). Journal of Hazardous Materials, 183(1-3), 602-608. doi:10.1016/j.jhazmat.2010.07.067Boyd, G. R., Reemtsma, H., Grimm, D. A., & Mitra, S. (2003). Pharmaceuticals and personal care products (PPCPs) in surface and treated waters of Louisiana, USA and Ontario, Canada. Science of The Total Environment, 311(1-3), 135-149. doi:10.1016/s0048-9697(03)00138-4ROBERTS, P., & THOMAS, K. (2006). The occurrence of selected pharmaceuticals in wastewater effluent and surface waters of the lower Tyne catchment. Science of The Total Environment, 356(1-3), 143-153. doi:10.1016/j.scitotenv.2005.04.031Kim, S. D., Cho, J., Kim, I. S., Vanderford, B. J., & Snyder, S. A. (2007). Occurrence and removal of pharmaceuticals and endocrine disruptors in South Korean surface, drinking, and waste waters. Water Research, 41(5), 1013-1021. doi:10.1016/j.watres.2006.06.034Yoon, Y., Ryu, J., Oh, J., Choi, B.-G., & Snyder, S. A. (2010). Occurrence of endocrine disrupting compounds, pharmaceuticals, and personal care products in the Han River (Seoul, South Korea). Science of The Total Environment, 408(3), 636-643. doi:10.1016/j.scitotenv.2009.10.049Ternes, T. A., Stüber, J., Herrmann, N., McDowell, D., Ried, A., Kampmann, M., & Teiser, B. (2003). Ozonation: a tool for removal of pharmaceuticals, contrast media and musk fragrances from wastewater? Water Research, 37(8), 1976-1982. doi:10.1016/s0043-1354(02)00570-5Rosal, R., Rodríguez, A., Perdigón-Melón, J. A., Mezcua, M., Hernando, M. D., Letón, P., … Fernández-Alba, A. R. (2008). Removal of pharmaceuticals and kinetics of mineralization by O3/H2O2 in a biotreated municipal wastewater. Water Research, 42(14), 3719-3728. doi:10.1016/j.watres.2008.06.008Fatta-Kassinos, D., Vasquez, M. I., & Kümmerer, K. (2011). Transformation products of pharmaceuticals in surface waters and wastewater formed during photolysis and advanced oxidation processes – Degradation, elucidation of byproducts and assessment of their biological potency. Chemosphere, 85(5), 693-709. doi:10.1016/j.chemosphere.2011.06.082Kasprzyk-Hordern, B., Dinsdale, R. M., & Guwy, A. J. (2009). 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Toxicity testing of wastewater and sewage sludge by biosensors, bioassays and chemical analysis. TrAC Trends in Analytical Chemistry, 22(5), 299-310. doi:10.1016/s0165-9936(03)00504-1Ten Berge, W. F. (1978). Breeding Daphnia magna. Hydrobiologia, 59(2), 121-123. doi:10.1007/bf00020772American Society for Testing and Materials (ASTM). 1987.Standard Guide for Conducting Renewal Life-Cycle Toxicity Tests with Daphnia Magna. Annual Book of ASTM Standards,Vol. E 1193, 765–781. Philadelphia: ASTM.Radjenović, J., Petrović, M., & Barceló, D. (2009). Fate and distribution of pharmaceuticals in wastewater and sewage sludge of the conventional activated sludge (CAS) and advanced membrane bioreactor (MBR) treatment. Water Research, 43(3), 831-841. doi:10.1016/j.watres.2008.11.043Lin, A. Y.-C., Lin, C.-A., Tung, H.-H., & Chary, N. S. (2010). Potential for biodegradation and sorption of acetaminophen, caffeine, propranolol and acebutolol in lab-scale aqueous environments. Journal of Hazardous Materials, 183(1-3), 242-250. doi:10.1016/j.jhazmat.2010.07.017Yang, S.-F., Lin, C.-F., Yu-Chen Lin, A., & Andy Hong, P.-K. (2011). Sorption and biodegradation of sulfonamide antibiotics by activated sludge: Experimental assessment using batch data obtained under aerobic conditions. Water Research, 45(11), 3389-3397. doi:10.1016/j.watres.2011.03.052Ternes, T. A., Herrmann, N., Bonerz, M., Knacker, T., Siegrist, H., & Joss, A. (2004). A rapid method to measure the solid–water distribution coefficient (Kd) for pharmaceuticals and musk fragrances in sewage sludge. Water Research, 38(19), 4075-4084. doi:10.1016/j.watres.2004.07.015Stevens-Garmon, J., Drewes, J. E., Khan, S. J., McDonald, J. A., & Dickenson, E. R. V. (2011). Sorption of emerging trace organic compounds onto wastewater sludge solids. Water Research, 45(11), 3417-3426. doi:10.1016/j.watres.2011.03.056Dionisi, D., Bertin, L., Bornoroni, L., Capodicasa, S., Papini, M. P., & Fava, F. (2006). Removal of organic xenobiotics in activated sludges under aerobic conditions and anaerobic digestion of the adsorbed species. Journal of Chemical Technology & Biotechnology, 81(9), 1496-1505. doi:10.1002/jctb.1561Byrns, G. (2001). The fate of xenobiotic organic compounds in wastewater treatment plants. Water Research, 35(10), 2523-2533. doi:10.1016/s0043-1354(00)00529-7Hyland, K. C., Dickenson, E. R. V., Drewes, J. E., & Higgins, C. P. (2012). Sorption of ionized and neutral emerging trace organic compounds onto activated sludge from different wastewater treatment configurations. Water Research, 46(6), 1958-1968. doi:10.1016/j.watres.2012.01.012Yang, S.-F., Lin, C.-F., Wu, C.-J., Ng, K.-K., Yu-Chen Lin, A., & Andy Hong, P.-K. (2012). Fate of sulfonamide antibiotics in contact with activated sludge – Sorption and biodegradation. Water Research, 46(4), 1301-1308. doi:10.1016/j.watres.2011.12.035Feng, W., & Nansheng, D. (2000). Photochemistry of hydrolytic iron (III) species and photoinduced degradation of organic compounds. A minireview. Chemosphere, 41(8), 1137-1147. doi:10.1016/s0045-6535(00)00024-2Rodríguez, E. M., Fernández, G., Álvarez, P. M., Hernández, R., & Beltrán, F. J. (2011). Photocatalytic degradation of organics in water in the presence of iron oxides: Effects of pH and light source. Applied Catalysis B: Environmental, 102(3-4), 572-583. doi:10.1016/j.apcatb.2010.12.041Beltrán, F. J., Aguinaco, A., García-Araya, J. F., & Oropesa, A. (2008). Ozone and photocatalytic processes to remove the antibiotic sulfamethoxazole from water. Water Research, 42(14), 3799-3808. doi:10.1016/j.watres.2008.07.019García-Araya, J. F., Beltrán, F. J., & Aguinaco, A. (2010). Diclofenac removal from water by ozone and photolytic TiO2 catalysed processes. Journal of Chemical Technology & Biotechnology, 85(6), 798-804. doi:10.1002/jctb.2363Rivas, F. J., Beltrán, F. J., & Encinas, A. (2012). Removal of emergent contaminants: Integration of ozone and photocatalysis. Journal of Environmental Management, 100, 10-15. doi:10.1016/j.jenvman.2012.01.025Rivas, F. J., Beltrán, F. J., Gimeno, O., & Acedo, B. (2001). Wet Air Oxidation Of Wastewater From Olive Oil Mills. Chemical Engineering & Technology, 24(4), 415-421. doi:10.1002/1521-4125(200104)24:43.0.co;2-cGIMENO, O., CARBAJO, M., BELTRAN, F., & RIVAS, F. (2005). Phenol and substituted phenols AOPs remediation. Journal of Hazardous Materials, 119(1-3), 99-108. doi:10.1016/j.jhazmat.2004.11.024Beltrán, F. J., Gimeno, O., Rivas, F. J., & Carbajo, M. (2006). Photocatalytic ozonation of gallic acid in water. Journal of Chemical Technology & Biotechnology, 81(11), 1787-1796. doi:10.1002/jctb.1605Aguinaco, A., Beltrán, F. J., García-Araya, J. F., & Oropesa, A. (2012). Photocatalytic ozonation to remove the pharmaceutical diclofenac from water: Influence of variables. 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Equilibrium, Kinetic, and Computational Studies on the Formation of Cu2+ and Zn2+ Complexes with an Indazole-Containing Azamacrocyclic Scorpiand: Evidence for Metal-Induced Tautomerism

Cu2+ and Zn2+ coordination chemistry of a new member of the family of scorpiand-like macrocyclic ligands derived from tris(2-aminoethyl)amine (tren) is reported. The new ligand (L1) contains in its pendant arm not only the amine group derived from tren but also a 6-indazole ring. Potentiometric studies allow the determination of four protonation constants. UV−vis and fluorescence data support that the last protonation step occurs on the indazole group. Equilibrium measurements in the presence of Cu2+ and Zn2+ reveal the formation of stable [ML1]2+, [MHL1]3+, and [ML1(OH)]+ complexes. Kinetic studies on the acid-promoted decomposition of the metal complexes were carried out using both absorbance and fluorescence detection. For Zn2+, both types of detection led to the same results. The experiments suggest that [ZnL1]2+ protonates upon addition of an acid excess to form [ZnHL1]3+ within the mixing time of the stopped-flow instrument, which then decomposes with a first-order dependence on the acid concentration. The kinetic behavior is more complex in the case of Cu2+. Both [CuL1]2+ and [CuHL1]3+ show similar absorption spectra and convert within the mixing time to a new intermediate species with a band at 750 nm, the process being reverted by addition of base. The intermediate then decomposes with a secondorder dependence on the acid concentration. However, kinetic experiments with fluorescence detection showed the existence of an additional faster step. With the help of DFT calculations, an interpretation is proposed in which protonation of [CuL1]2+ to form [CuHL1]3+ would involve dissociation of the tren-based NH group in the pendant arm and coordination of a 2H-indazole group. Further protonation would lead to dissociation of coordinated indazole, which then will convert to the more stable 1H tautomer in a process signaled by fluorescence changes that would not be affecting to the d−d spectrum of the complex

Fe3O4-TiO2 Thin Films in Solar Photocatalytic Processes

The optical properties of 5wt% Fe3O4-TiO2 thin films were evaluated in detail with the aim of proposing a mechanism for solar photocatalytic processes and highlighting the advantages over the use of bare TiO2. The results showed that the incorporation of 5wt% Fe3O4 enhanced the optical properties by a redshift to a wavelength in the visible range, reducing the anatase/rutile band gap energy from 3.2 eV to 2.8 eV. Photoluminescence studies reveal a superior separation efficiency of photoexcited electron-hole pairs when Fe3O4 nanoparticles (NPs) are present in the photocatalyst. X-ray photoelectron spectroscopy spectra confirm the presence of Fe3O4 and existence of a chemical bonding between TiO2 and Fe3O4 NPs. Moreover, in this study, a mechanism of solar photocatalytic processes involving Fe3O4-TiO2 thin films is proposed and it is supported by experimental results. Finally, solar photocatalytic experiments were carried out, indicating that the effectiveness for the removal of the selected pharmaceutical is considerably improved when the composite material is used as catalyst. Furthermore, it was demonstrated that the photocatalytic activity of the prepared Fe3O4-TiO2 thin films depends on their thickness, achieving the highest pharmaceutical removal yields using the 2 mu m thick sample. The stability and reusability of the catalyst was confirmed studying the photocatalytic activity over three cycles

Enhanced Artificial Enzyme Activities on the Reconstructed Sawtoothlike Nanofacets of Pure and Pr-Doped Ceria Nanocubes

In this work, a simple one-step thermal oxidation process was established to achieve a significant surface increase in {110} and {111} nanofacets on well-defined, pure and Pr-doped, ceria nanocubes. More importantly, without changing most of the bulk properties, this treatment leads to a remarkable boost of their enzymatic activities: from the oxidant (oxidase-like) to antioxidant (hydroxyl radical scavenging) as well as the paraoxon degradation (phosphatase-like) activities. Such performance improvement might be due to the thermally generated sawtoothlike {111} nanofacets and defects, which facilitate the oxygen mobility and the formation of oxygen vacancies on the surface. Finally, possible mechanisms of nanoceria as artificial enzymes have been proposed in this manuscript. Considering the potential application of ceria as artificial enzymes, this thermal treatment may enable the future design of highly efficient nanozymes without changing the bulk composition.This work has been supported by the Ministry of Science, Innovation and Universities of Spain with Reference Numbers of ENE2017-82451-C3-2-R, MAT2016-81118-P and MAT2017-87579-R. The research projects funded by the Natural Science Foundation of Shandong Province (Grant ZR2017LB028), Key R&D Program of Shandong Province (Grant 2018GSF118032), and Fundamental Research Funds for the Central Universities (Grant 18CX02125A) in China are also acknowledged. TEM/STEM data were obtained at DMEUCA node of the Spanish Unique Scientific and Technological Infrastructure (ICTS) of Electron Microscopy of Materials ELECMIM. M. Tinoco thanks the FPU Scholarship Program (Grant AP2010-3737) from Ministry of Education of Spain. H. Pan is grateful for financial support (Grant 201406140130) from the Chinese Scholarship Council to accomplish her Ph.D. study at the University of Cadiz (Spain). J. M. Gonzalez, G. Blanco, and X. Chen are also grateful for the financial support from the joint project (Proyectos Integradores, Grant PI20201) in IMEYMAT of the University of Cadiz

Preparación y caracterización de láminas delgadas de óxido de vanadio obtenidas por vía sol-gel y recubrimiento por inmersión

Resumen del proyecto de líneas prioritarias titulado "Preparación y caracterización de láminas delgadas de óxido de vanadio obtenidas por vía sol-gel y recubrimiento por inmersión" del IMEYMAT

Unraveling the effect of silent, intronic and missense mutations on VWF splicing: contribution of next generation sequencing in the study of mRNA

Large studies in von Willebrand disease patients, including Spanish and Portuguese registries, led to the identification of >250 different mutations. It is a challenge to determine the pathogenic effect of potential splice site mutations on VWF mRNA. This study aimed to elucidate the true effects of 18 mutations on VWF mRNA processing, investigate the contribution of next-generation sequencing to in vivo mRNA study in von Willebrand disease, and compare the findings with in silico prediction. RNA extracted from patient platelets and leukocytes was amplified by RT-PCR and sequenced using Sanger and next generation sequencing techniques. Eight mutations affected VWF splicing: c.1533+1G>A, c.5664+2T>C and c.546G>A (p.=) prompted exon skipping; c.3223-7_3236dup and c.7082-2A>G resulted in activation of cryptic sites; c.3379+1G>A and c.7437G>A) demonstrated both molecular pathogenic mechanisms simultaneously; and the p.Cys370Tyr missense mutation generated two aberrant transcripts. Of note, the complete effect of three mutations was provided by next generation sequencing alone because of low expression of the aberrant transcripts. In the remaining 10 mutations, no effect was elucidated in the experiments. However, the differential findings obtained in platelets and leukocytes provided substantial evidence that four of these would have an effect on VWF levels. In this first report using next generation sequencing technology to unravel the effects of VWF mutations on splicing, the technique yielded valuable information. Our data bring to light the importance of studying the effect of synonymous and missense mutations on VWF splicing to improve the current knowledge of the molecular mechanisms behind von Willebrand disease. clinicaltrials.gov identifier:02869074

Unraveling the effect of silent, intronic and missense mutations on VWF splicing : contribution of next generation sequencing in the study of mRNA

Large studies in von Willebrand disease patients, including Spanish and Portuguese registries, led to the identification of >250 different mutations. It is a challenge to determine the pathogenic effect of potential splice site mutations on VWF mRNA. This study aimed to elucidate the true effects of 18 mutations on VWF mRNA processing, investigate the contribution of next-generation sequencing to in vivo mRNA study in von Willebrand disease, and compare the findings with in silico prediction. RNA extracted from patient platelets and leukocytes was amplified by RT-PCR and sequenced using Sanger and next generation sequencing techniques. Eight mutations affected VWF splicing: c.1533+1G>A, c.5664+2T>C and c.546G>A (p.=) prompted exon skipping; c.3223-7_3236dup and c.7082-2A>G resulted in activation of cryptic sites; c.3379+1G>A and c.7437G>A) demonstrated both molecular pathogenic mechanisms simultaneously; and the p.Cys370Tyr missense mutation generated two aberrant transcripts. Of note, the complete effect of three mutations was provided by next generation sequencing alone because of low expression of the aberrant transcripts. In the remaining 10 mutations, no effect was elucidated in the experiments. However, the differential findings obtained in platelets and leukocytes provided substantial evidence that four of these would have an effect on VWF levels. In this first report using next generation sequencing technology to unravel the effects of VWF mutations on splicing, the technique yielded valuable information. Our data bring to light the importance of studying the effect of synonymous and missense mutations on VWF splicing to improve the current knowledge of the molecular mechanisms behind von Willebrand disease. identifier:02869074

Molecular and clinical profile of von Willebrand disease in Spain (PCM-EVW-ES) : comprehensive genetic analysis by next-generation sequencing of 480 patients

Molecular diagnosis of patients with von Willebrand disease is pending in most populations due to the complexity and high cost of conventional molecular analyses. The need for molecular and clinical characterization of von Willebrand disease in Spain prompted the creation of a multicenter project (PCM-EVW-ES) that resulted in the largest prospective cohort study of patients with all types of von Willebrand disease. Molecular analysis of relevant regions of the VWF, including intronic and promoter regions, was achieved in the 556 individuals recruited via the development of a simple, innovative, relatively low-cost protocol based on microfluidic technology and next-generation sequencing. A total of 704 variants (237 different) were identified along VWF, 155 of which had not been previously recorded in the international mutation database. The potential pathogenic effect of these variants was assessed by in silico analysis. Furthermore, four short tandem repeats were analyzed in order to evaluate the ancestral origin of recurrent mutations. The outcome of genetic analysis allowed for the reclassification of 110 patients, identification of 37 asymptomatic carriers (important for genetic counseling) and re-inclusion of 43 patients previously excluded by phenotyping results. In total, 480 patients were definitively diagnosed. Candidate mutations were identified in all patients except 13 type 1 von Willebrand disease, yielding a high genotype-phenotype correlation. Our data reinforce the capital importance and usefulness of genetics in von Willebrand disease diagnostics. The progressive implementation of molecular study as the first-line test for routine diagnosis of this condition will lead to increasingly more personalized and effective care for this patient population