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The use of metallic nanoparticles in the field of orthopaedics as antimicrobial components of coatings is receiving particular attention. An innovative approach has been developed whereby various metal/metal oxide nanoparticles are used to prevent infection occurring on the surface of prostheses. In this study nano metallic oxides (zinc oxide - ZnO and tungsten oxide - WO3) were used. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of each nanoparticulate were determined against four species of bacteria (Staphylococcus aureus, Escherichia coli, Staphylococcus epidermidis and Pseudomonas aeruginosa). Subsequently the nanoparticles were prepared in a suspension of ethanol and sprayed onto the surface of glass using electrohydrodynamic deposition. Quantitative assessments as regards the antimicrobial properties of these coated samples were carried out. Comparisons of the antibacterial properties demonstrated that 2500 µg/ml or above of the oxides were required to kill the species of bacteria tested. WO3 was the most effective oxide tested in suspension using growth inhibition tests. However, coated samples demonstrated that ZnO was more bactericidal than WO3 under these conditions.

This article presents the data on α-Fe 2 O 3 nanoparticles synthesized via Pechini method using iron(III) oxide precursor from steel industry. It is important to highlight the added value that is given to an industrial waste. The samples were characterized by thermal analysis (DTA, TG), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The TG showed three mass changes, whereas DTA resulted in three anomalies. X-ray diffraction pattern of the samples disclosed rhombohedral structure characteristic of the nanocrystalline α-Fe 2 O 3 phase. The crystallite size was estimated for each thermal treatment. Fourier transform infrared spectroscopy confirms the phase purity of prepared nanoparticles. A detailed study on the local structure of the samples was carry out in the region of 800 and 400 cm −1 , where the associated bands of Fe–O bonds are presents. The data have not been reported nor discussed for now.

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En este trabajo se ha utilizado el método de precursor polimérico (método de Pechini) para sintetizar dióxido de titanio, proceso que ha permitido tener un mayor control sobre la pureza del óxido y el tipo de fase que ha presentado el material obtenido, fase anatasa en el presente caso. Durante el proceso de síntesis se ha obtenido una resina que se ha caracterizado utilizando la espectroscopia de Resonancia Magnética Nuclear (RMN) y la espectroscopia infrarroja con transformada de Fourier (FTIR) para determinar su estructura y con base en ella se ha propuesto un modelo para la conformación de la misma. Posteriormente esta resina se ha sometido a un tratamiento térmico para obtener los polvos cerámicos que se han caracterizado empleando diferentes técnicas, principalmente, difracción de rayos X (DRX) y microscopia electrónica (MET y MEB). Los resultados indican que se puede obtener TiO 2 fase anatasa a los 450ºC con un tamaño de partícula <100nm. Palabras claves: Óxido de titanio; anatasa; método de Pechini; caracterización. TiO 2 synthesized by the method of polymeric precursor (Pechini): structure of the intermediate resineIn this work, the polymeric precursor method (Pechini method) was used to synthesize titanium dioxide. This process allowed a bigger control on the purity of the oxide and the crystalline phase present in the material. In this case, the principal phase was anatase. The resine obtained in this process was characterized using NMR and IR spectroscopy to determine their structure. With this information we proposed a resine structure model. To finish the process, the resin was thermally treated to obtain TiO 2 . This oxide was characterized using different techniques: ray-X diffraction (RDX) and electron microscopy (TEM and SEM). The results indicated that the TiO 2 anatase phase can be obtained at 450ºC with a particle size <100nm.Keywords: Titanium dioxide; anatase; Pechini method; characterization. INTRODUCCIÓNEl dióxido de titanio, TiO 2 , es un compuesto de gran interés tecnológico. El TiO 2 presenta cuatro fases cristalinas: rutilo (estructura tetragonal), anatasa (estructura octaédrica), brookita (estructura ortorrómbica) y una de alta presión tipo α-PbO 2 [1]. El dióxido de titanio, especialmente en la variedad de anatasa, es ampliamente utilizado como fotocatalizador debido a que posee un adecuado valor de banda prohibida (∼3eV). Además es utilizado como pigmento blanco, recubrimiento anticorrosivo, sensor de gases, absorbente de rayos UV en productos cosméticos y de manera general en la industria cerámica [2]. También es muy utilizado para fotodegradar moléculas orgánicas presentes en el agua y en el aire.El polvo cerámico de dióxido de titano puede ser obtenido utilizando métodos como: Sol-Gel obtener una disolución líquida transparente. Como en el sistema se encuentran presentes cationes es posible que se conformen quelatos polibásicos, ácidos, que posteriormente, por calentamiento, se polimerizan dando origen a una resina viscosa [6,7]. Comúnmente, en el proceso Pechini, se utiliza u...

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