Improvement of submerged culture conditions to produce colorants by Penicillium purpurogenum

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Nanostructured TiO2-based composites for light absorption

Metal oxidenanocomposites were prepared by two different routes: polyol and sol-gel. Characterization by X ray diffraction showed that the first processproducesdirectly a two-phase material, while the sol-gelpowder never showed second phase below 600 degrees C. Light spectroscopy of the treated powders indicated similarities for the processed materials. Although the overall material compositions are about the same, different structural characteristics are found for each processing. With the exception of Ti-Zn materials, all the double metal oxide powders showed higher absorbance than either TiO2 powder.

Synthesis and characterization of nanostructured TiO2-SnO2 composite

Nanostructured composites based on titanium dioxide have been studied in order to improve optical and photo-catalytic properties, as well as their performance in gas sensors. In this work, titanium and tin dioxides were simultaneously synthesized by the polyol method resulting in TiO2 platelet coated with SnO2 nanoparticles as was observed by scanning electron microscopy. The thermal analysis showed that the combined synthesis promotes more easily the crystallization of the TiO2 rutile phase. The composite obtained after heat treatment at 500 degrees C showed to be formed of almost only rutile phases of both oxides. The optical properties analyzed by UV-Vis spectroscopy showed that the combined oxides have higher absorbance, which reinforces a model found in the literature based on the flow of photo-generated electrons to the conduction band of SnO2 delaying the recombination of charges.

Uma nova abordagem analítica sobre teores de 'Zn' por HR-CSAAS em plantas medicinais voltadas ao emagrecimento

The following research project deals with the development of new analytical procedures aimed at the identification and quantification of the element zinc in different fractions of vegetable drugs used for weight loss, using the high-resolution continuum source atomic absorption spectrometry in flame. The determination of the levels of zinc was made in an AnalytikJena ContrAA 300 spectrometer in the principal line of Zn at 213.857 nm and wavelength integrated absorbance equal to 3 pixels. Calibration curves were obtained with linear dynamic range from 0.10 to 1.00 mg L-1, correlation coefficient equal to 0.9991 and limit of detection equal to 0.020 mg L-1. The total Zn content in the samples obtained after microwave-assisted acid digestion system were: 28.06 mg kg-1 (Artichoke), 31.49 mg kg-1 (Chamomile), 77.16 mg kg-1 (Gorse), 105.38 mg kg-1 (Horsetail), 32.37 mg kg-1 (Fennel) and 5.00 mg kg-1 (Senna). The extraction in aqueous environment assisted by microwave radiation produced extracts containing: 5.40 mg kg-1 (Artichoke), 10.65 mg kg-1 (Chamomile), 14.83 mg kg-1 (Gorse), 18.90 mg kg-1 (Horsetail), 7.80 mg kg-1 (Fennel), 3.24 mg kg-1 (Senna), corresponding to 19%, 34%, 19%, 18%, 24% and 64% of their total content of Zn, respectively. The amounts of Zn in the extracted samples from some plants indicate that this metal was strongly bounded to the plant's matrix. The sequential extraction using solvents and mixtures with different polarities (n-hexane, ethyl acetate, propanol, methanol, ethanol-water 1:1 (v/v), water) aimed the separation of different Zn containing species and water was considered the most efficient extractor. The Zn contents extracted were: 14.82 mg kg-1 (Artichoke), 16.82 mg kg-1 (Chamomile), 34.09 mg kg-1 (Gorse), 4.75 mg kg-1 (Senna), corresponding to 53% in the first two samples, 44% and 95% for the last two, respectively. It was observed that Zn is found complexed under

Técnica híbrida de plasma para a deposição de filmes de alumina

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Materiais derivados de hidróxidos duplos lamelares: síntese, caracterização e aplicação em adsorção e processos avançados de oxidação

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of first derivative spectrophotometric method for quantification of darunavir in tablets

Aims: Darunavir is widely used in HIV/AIDS therapy. It is a HIV protease inhibitor that has excellent efficacy against the virus. The aim of this study is to develop and validate an analytical method fast and free of interferences for determination of darunavir ethanolate as raw material and tablet dosage form. Methodology: As the formulation excipients show high interference in darunavir determination by a direct UV absorption measurement a derivative spectrophotometry was applied. A selective, easy and fast method was achieved employing simple and cheap instrumentation by using first-order derivative spectrophotometry. Results: The first-derivation of spectrum of the drug measured between 200 and 400 nm allowed identification of the analyte and showed absence of placebo interference. The assay was based on the absorbance at 276nm. The linear concentration range was established from 11 to 21 μg/mL. The intra-day and inter-day precision expressed as RSD was 0.06% and 3.75% respectively with mean recovery of 99.84%. Conclusion: The proposed analytical method is able to quantify darunavir as raw material and tablets and can be used routinely by any laboratory applying a spectrophotometer with a derivative accessory. The great difference of the method proposed here is that it proves to be free of placebo interferences as well as simple, fast and low cost.

A platform for designing quantitative infrared spectrophotometric method for drugs and pharmaceuticals analysis: a rediscover for an ecological and safer technique in the routine quality control laboratories

This paper describes the importance of an innovative analytical technique for drugs and pharmaceuticals quantification, using Fouriertransform infrared (FTIR) transmission spectroscopy. This method does not use organic solvents, which is one great advantage over the most common analytical methods. This fact contributes to minimize the generation of organic solvent waste by the industry and thereby reduces the impact of its activities on the environment. The method involved absorbance measurements of the band corresponding to one of the chosen group in the molecule. Obviously, the method should be validated according to ICH guidelines, showing linearity, precision, accuracy and robustness, over a concentration range, using small amounts to prepare the analyte. The validated method is able to quantify drugs and pharmaceuticals and can be used as an environmentally friendly alternative for the routine analysis in pharmaceutical industry quality control.

Development and validation of the quantitative analysis of cefuroxime sodium in powder for injection by infrared spectroscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development and validation of the quantitative analysis of ampicillin sodium in powder for injection by Fourier-transform infrared spectroscopy (FT-IR)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biossorção & biodegradação de azo corante: desenvolvimento de processos utilizando resíduos como fonte de microorganismos = Azo dye biosorption & biodegradation : process development with residues as source of microorganisms

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Nanostructured TiO2-based composites for light absorption

Metal oxide nanocomposites were prepared by two different routes: polyol and sol-gel. Characterization by X ray diffraction showed that the first process produces directly a two-phase material, while the sol-gel powder never showed second phase below 600°C. Light spectroscopy of the treated powders indicated similarities for the processed materials. Although the overall material compositions are about the same, different structural characteristics are found for each processing. With the exception of Ti-Zn materials, all the double metal oxide powders showed higher absorbance than either TiO2 powder.

Synthesis and characterization of nanostructured TiO2-SnO2 composite

Nanostructured composites based on titanium dioxide have been studied in order to improve optical and photo-catalytic properties, as well as their performance in gas sensors. In this work, titanium and tin dioxides were simultaneously synthesized by the polyol method resulting in TiO2 platelet coated with SnO2 nanoparticles as was observed by scanning electron microscopy. The thermal analysis showed that the combined synthesis promotes more easily the crystallization of the TiO2 rutile phase. The composite obtained after heat treatment at 500 °C showed to be formed of almost only rutile phases of both oxides. The optical properties analyzed by UV-Vis spectroscopy showed that the combined oxides have higher absorbance, which reinforces a model found in the literature based on the flow of photo-generated electrons to the conduction band of SnO2 delaying the recombination of charges.

Investigação das propriedades ópticas, morfológicas e elétricas da heterojunção SnO2: Ce3+/ GaAs

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da adição de flúor e cálcio no gel clareador a base de peróxido de hidrogênio na penetração, cor e microdureza

The objective of this study was to evaluate the effect of adding calcium ions and fluoride in the formulation of a whitening gel 35% hydrogen peroxide in its penetration through the dental structure, whitening efficacy and surface hardness of dental enamel. 80 teeth bovine incisors were used, which were obtained enamel and dentin disks of the buccal surface with 6mm diameter and 2mm thick (1 mm of enamel and dentin 1mm). The samples were divided into four groups stratified according to the protective substance / remineralizing added to the gel of hydrogen peroxide 35%: Group Ca - Calcium gluconate 0.5%; Group F - Sodium fluoride 0.2%; Group Ca + F - Calcium gluconate 0.5% and Sodium Fluoride 0.2%; Control group - no substance was added. The initial color of the samples and the hardness of the enamel were measured before the bleaching procedures. The specimens from each group were placed on a metallic support on which there was a simulated pulp chamber, which was filled with acetate buffer to collect and stabilize the penetrated peroxide. The respective bleaching treatments were applied 3 times, total of 30 minutes of application. The amount of peroxide which passed through the samples was determined by absorbance spectrophotometry. The hardness of the samples was measured immediately after bleaching. Next, the samples were immersed in artificial saliva for 7 days, after which the final color was evaluated. Data were statistically analyzed adopting a 5% significance level