The Effect of Sulphate Doping on NanosizedTiO2andMoOx/TiO2Catalysts in Cyclohexane Photooxidative Dehydrogenation

The effect of sulphate doping of titania in promoting activity and selectivity ofMoOx/TiO2catalysts for the cyclohexane photooxidative dehydrogenation has been investigated in a gas-solid fluidized bed reactor. Sulphate and/or molybdate-modified titania catalysts were prepared by incipient wet impregnation of nanosized (5–10 nm crystallite size) samples. At 60% of titania surface coverage byMoOx, sulphate surface density was obtained up to 19μmol/m2without formation ofMoO3. The catalysts were characterized byN2adsorption-desorption at−196∘C, micro-Raman and UV-visible reflectance spectroscopy, thermogravimetric analysis coupled with mass spectroscopy (TG-MS), and mass titration. Unsulphated and sulphated titania are both active in cyclohexane total oxidation, but sulphate doping of titania has a detrimental effect on the reaction rate. On Mo-based catalysts, polymolybdate species enabled sulphated titania to convert cyclohexane to benzene (99% selectivity) and cyclohexene, reducing at zero the formation ofCO2. Cyclohexane conversion to benzene is almost linearly dependent on sulphate surface density, resulting in enhanced yield to benzene. The enhanced photooxidative dehydrogenation activity and benzene yield by sulphate doping could be attributed to the increase of surface acidity and, as a consequence, of cyclohexane adsorption

Photocatalytic ethanol oxidative dehydrogenation over Pt/TiO 2: Effect of the addition of blue phosphors

Ethanol oxidative dehydrogenation over Pt/TiO 2 photocatalyst, in the presence and absence of blue phosphors, was performed. The catalyst was prepared by photodeposition of Pt on sulphated TiO 2. This material was tested in a gas-solid photocatalytic fluidized bed reactor at high illumination efficiency. The effect of the addition of blue phosphors into the fluidized bed has been evaluated. The synthesized catalysts were extensively characterized by different techniques. Pt/TiO 2 with a loading of 0.5wt of Pt appeared to be an active photocatalyst in the selective partial oxidation of ethanol to acetaldehyde improving its activity and selectivity compared to pure TiO 2. In the same way, a notable enhancement of ethanol conversion in the presence of the blue phosphors has been obtained. The blue phosphors produced an increase in the level of ethanol conversion over the Pt/TiO 2 catalyst, keeping at the same time the high selectivity to acetaldehyde. Copyright © 2012 J. J. Murcia et al.Peer Reviewe

Plasmonic optical fiber meta-tip for cancer biomarkers detection

Sensors based on Lab-On-Tip (LOT) technology, where suitably designed nanostructures are integrated onto the end face of an optical fiber, are of strategic importance especially in medicine and clinical diagnostics, where minia- turization and portability are key characteristics. To improve the performance of LOT biosensors, we proposed the integration of the optical fiber with plasmonic Metasurfaces (Optical fiber meta-tip, OFMT), sensibly enhancing the light-matter interaction. Here we report on the remarkable capabilities of plasmonic OFMTs to perform label-free detection of cancer biomarkers with improved performances with respect to state-of-the-art optical fiber senso

Photocatalytic removal of patent blue V dye on Au-TiO2 and Pt-TiO2 catalysts

In this work it was studied the efficiency of a photocatalytic process for the removal of patent blue V. This dye is very difficult to remove by conventional treatments such as adsorption or coagulation therefore the photocatalytic process is a very interesting alternative for the removal this dye mainly because it does not require expensive oxidants and it can be carried out at mild temperatures and pressures. In this work it was tested the efficiency of Au-TiO2 and Pt-TiO2 photocatalysts in the Patent blue V removal. The Au-TiO2 catalysts were prepared by two different methods: chemical reduction and photochemical deposition; Pt-TiO2 catalysts were obtained only by photochemical deposition. In the synthesis of the catalysts prepared by photochemical deposition, it was evaluated the influence of some parameters, such as deposition time and the intensity of the light source over the physicochemical properties and photocatalytic activity of the materials obtained. An analysis of the effect of the catalyst dosage and initial patent blue V concentration over the dye degradation efficiency was also attempted. In general, it was observed that the presence of Au or Pt on TiO2 enhances the patent blue V photodegradation; it was found that noble metal particle size and distribution on TiO2 surface are important factors influencing the dye removal. The highest dye degradation was obtained over the Au-TiO2 catalyst prepared by photochemical deposition, using high light intensity and 15 min of deposition time during the synthesis. A discoloration and a total organic carbon (TOC) removal of 93 and 67% respectively, were obtained over this material after 180 min of UV irradiation. These values are higher than that the obtained on S-TiO2 (discoloration and TOC removal of about 25% and 3%, respectively)

Label-free fiber optic optrode for the detection of class C beta-lactamases expressed by drug resistant bacteria

This paper reports the experimental assessment of an automated optical assay based on label free optical fiber optrodes for the fast detection of class C beta-lactamases (AmpC BLs), actually considered as one of the most important sources of resistance to beta-lactams antibiotics expressed by resistant bacteria. Reflection-type long period fiber gratings (RT-LPG) have been used as highly sensitive label free optrodes, while a higher affine boronic acid based ligand was here selected to enhance the overall assay performances compared to those obtained in our first demonstration. In order to prove the feasibility analysis towards a fully automated optical assay, an engineered system was developed to simultaneously manipulate and interrogate multiple fiber optic optrodes in the different phases of the assay. The automated system tested in AmpC solutions at increasing concentrations demonstrated a limit of detection (LOD) of 6 nM, three times better when compared with the results obtained in our previous work. Moreover, the real effectiveness of the proposed optical assay has been also confirmed in complex matrices as the case of lysates of Escherichia coli overexpressing AmpC. (C) 2017 Optical Society of Americ

Intravitreal Brolucizumab for Pachychoroid Neovasculopathy Associated With Chronic Central Serous Chorioretinopathy

Purpose: To evaluate the anatomical and functional outcomes of intravitreal brolucizumab in eyes with chronic central serous chorioretinopathy complicated by pachychoroid neovasculopathy. Methods: Retrospective analysis of 34 eyes treated with intravitreal brolucizumab. Twenty-five eyes (73.5%) had been treated with other anti-vascular endothelial growth factor agents before switching to brolucizumab, whereas nine eyes were naïve. Outcome measures included the change of central foveal thickness and subfoveal choroidal thickness, evaluation of sub/intraretinal fluid on optical coherence tomography, and change in best-corrected visual acuity. Results: Before starting brolucizumab, 23 eyes showed subretinal fluid, 8 both subretinal and intraretinal fluid, and 3 intraretinal fluid only. At the last visit, 22 eyes (64.7%) showed complete reabsorption of both intraretinal and subretinal fluid, whereas subretinal fluid was still present in 8 eyes (23.5%), and both intraretinal and subretinal fluid in 4 eyes (11.8%). The mean number of brolucizumab injections required to achieve complete fluid reabsorption was 2.8 ± 1.8. central foveal thickness decreased from 317.8 ± 109.3 μm to 239.8 ± 74.8 μm (P = 0.0005) and subfoveal choroidal thickness decreased from 399.3 ± 86.2 μm to 355.5 ± 92.7 μm at the end of the follow-up period (P = 0.0008). The mean logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.4 ± 0.2 to 0.3 ± 0.2 at 1 month after the first injection and remained stable at the same values at the end of the follow-up period (P = 0.04). Conclusions: Intravitreal brolucizumab is effective for the treatment of naïve and recalcitrant pachychoroid neovasculopathy. Translational relevance: Intravitreal brolucizumab may represent an option in patients with pachychoroid neovasculopathy complicating chronic central serous chorioretinopathy