An evaluation of cell proliferation and adhesion on biocompatible film supports was performed. A series of films were compression molded from commercially available poly (L-lactide), PLLA, and poly(epsilon-caprolactone), PCL, and from their melt mixed blends (PLLA/PCL blends). These were compared with compression molded films of PLLA-b-PCL model diblock copolymers. The samples were analyzed by differential scanning calorimetry (DSC), contact angle measurements, and scanning force microscopy (SFM). Cell adhesion and proliferation were performed with monkey derived fibroblasts (VERO) and with osteoblastic cells obtained either enzymatically or from explants cultures of Sprague-Dawley rat calvaria. Migration studies were performed with bone explants of the same origin. The results obtained indicate that although all materials tested were suitable for the support of cellular growth, a PLLA-b-PCL diblock copolymer sample with 93% PLLA was significantly more efficient. This sample exhibited a unique surface morphology with long range ordered domains (of the order of 2-3 mum) of edge-on PLLA lamellae that can promote "cell contact guidance." The influence of other factors such as chemical composition, degree of crystallinity, and surface roughness did not play a major role in determining cell preference toward a specific surface for the materials employed in this work.

No abstract

Available online xxx Keywords:TiO 2 Photocatalyst Microscopy Nanoparticles Morphologic-control a b s t r a c t This paper provides direct evidence to support the role of capping agents in controlling the evolution of TiO 2 seeds into nanocrystals with a specific shape. Starting with Ti(OBut) 4 and using oleid acid, oleylamine, dioleamide, 11-aminoundecanoic acid, arginine, trifluroacetic acid or HF as capping agents, mainly TiO 2 truncated octahedrons enclosed by {1 0 1} and {0 0 1} facets were obtained. We could also selectively obtain square, rods and rounded rhombic-shaped nanoparticles by growing of {0 1 0} facets by adding oleic acid and oleylamine in ratio 6:4, respectively, while all other parameters were kept the same. This research not only offers new insights into the role played by a capping agent in shape-controlled synthesis but also provides, a versatile approach to controlling the shape of metal oxide nanocrystals. Fotocatalizadores Microscopía NanopartículasControl-morfológico r e s u m e n El presente trabajo proporciona una evidencia directa del papel de los surfactantes en el control de la cristalización de nanopartículas de TiO 2 con una determinada morfología.Empleando Ti(OBut) 4 como producto de partida y usando ácido oleico, oleilamina, dioleilamida, ácido 11-aminoundecanoico, arginina, ácido trifluoroacético o HF como surfactantes se han obtenido, principalmente y de un modo selectivo, octaedros truncados de TiO 2 , formados por caras {1 0 1} y {0 0 1}. También se han obtenido de modo selectivo cubos, varillas y romboedros-redondeados, por crecimiento de las caras {0 1 0}, mediante la adición de ácido oleico y oleilamina en relación de 6:4, respectivamente, mientras que el resto de paráme-tros se mantuvieron iguales. Esta investigación no sólo ofrece nuevas perspectivas sobre el papel desempeñado por un surfactante en la obtención de nanocristales con una morfología específica, sino que también ofrece un enfoque versátil para controlar la forma final de nanopartículas de óxidos metálicos.

Ti0 2 nanoparticles with tailored morphology have been synthesized under exceptionally soft conditions. The strategy is based on the use of a non-aqueous alcoholic reaction medium in which water traces, coming either from the air (atmospheric water) or from an ethanol-water azeotropic mixture (ethanol 96%), are incorporated in order to accelerate hydrolysis of the Ti-precursor. Moreover, organic surfactants have been used as capping agents so as to tailor crystal growth in certain preferential directions. Combinations of oleic acid and oleylamine, which lead to the formation of another surfactant, dioleamide, are employed instead of fluorine-based compounds, thus increasing the sustainability of the process. As a result, Ti0 2 nanostructured hierarchical microspheres and individual nanoparticles with exposed high-energy facets can be obtained at atmospheric pressure and temperatures as low as 78 °C.

This work focuses on the coupling of three different approaches into the same reactor at 11 the same time: microfluidic cells, anodic oxidation with diamond anodes and an electro-12 Fenton process. In order to supply oxygen a jet aerator was used and a CB/PTFE 13 Duocel ® Al foam cathode was installed to promote the formation of hydrogen peroxide. 14 This novel concept is applied for the direct treatment (without the addition of salts or 15 other reagents) of soil washing wastes obtained in the remediation of soil spiked with 16 clopyralid. Results obtained pointed out that this approach can increase the efficiency of 17 the process by folds as compared to traditional treatment technologies. The chemical 18 analysis of the intermediates showed different reaction mechanisms: anodic oxidation, 19 electro-Fenton and a negligible contribution of coagulation. The coupled system studied 20 in this work present several advantages such as high treatment efficiency and short 21 treatment time which indicates that the development of electrochemical reactors for 22 diluted liquid wastes is progressing in an adequate direction.