Paulo Sergio Tonello

Publications (3)7.92 Total impact

• Article: Determination of labile inorganic and organic species of Al and Cu in river waters using the diffusive gradients in thin films technique.

  Paulo Sergio Tonello, Danielle Goveia, André Henrique Rosa, Leonardo Fernandes Fraceto, Amauri Antonio Menegário
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  ABSTRACT: The diffusive gradients in thin films (DGT) technique, using a diffusive gel or a restrictive gel, was evaluated for the determination of labile inorganic and organic species of Al and Cu in model synthetic solutions and river water samples. Experiments were performed both in situ and in the laboratory. In the solutions containing Al ions, the major labile fraction consisted of inorganic species. The organic complex fractions were mainly kinetically inert. For the model Cu solutions, the most labile fraction consisted of inorganic species; however, significant amounts of labile organic complexes of Cu were also present. A comparison was made between the results obtained using restrictive gel DGT and tangential flow ultrafiltration (TF-UF). The Cu fraction determined by restrictive gel DGT (corresponding to the "free" ions plus the labile fraction of small molecular size complexes) was larger than that determined by TF-UF (corresponding to all small molecular size ions), suggesting that the techniques exhibited different porosities for discrimination of inorganic species. For the river water samples analyzed in the laboratory, less than 45% of the analytes were present in labile forms, with most being organic species. For the in situ measurements, the labile inorganic and organic fractions were larger than those obtained in the laboratory analyses. These differences could have been due to errors incurred during sample collection and storage. All results were consistent with those found using two different methods, namely, solid-phase extraction and the DGT technique employing the apparent diffusion coefficient.
  Analytical and Bioanalytical Chemistry 03/2011; 399(7):2563-70. · 3.78 Impact Factor
• Article: Controlled release system for ametryn using polymer microspheres: preparation, characterization and release kinetics in water.

  Renato Grillo, Anderson do Espirito Santo Pereira, Nathalie Ferreira Silva de Melo, Raquel Martins Porto, Leandro Oliveira Feitosa, Paulo Sergio Tonello, Newton L Dias Filho, André Henrique Rosa, Renata Lima, Leonardo Fernandes Fraceto
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  ABSTRACT: The purpose of this work was to develop a modified release system for the herbicide ametryn by encapsulating the active substance in biodegradable polymer microparticles produced using the polymers poly(hydroxybutyrate) (PHB) or poly(hydroxybutyrate-valerate) (PHBV), in order to both improve the herbicidal action and reduce environmental toxicity. PHB or PHBV microparticles containing ametryn were prepared and the efficiencies of herbicide association and loading were evaluated, presenting similar values of approximately 40%. The microparticles were characterized by scanning electron microscopy (SEM), which showed that the average sizes of the PHB and PHBV microparticles were 5.92±0.74 μm and 5.63±0.68 μm, respectively. The ametryn release profile was modified when it was encapsulated in the microparticles, with slower and more sustained release compared to the release profile of pure ametryn. When ametryn was associated with the PHB and PHBV microparticles, the amount of herbicide released in the same period of time was significantly reduced, declining to 75% and 87%, respectively. For both types of microparticle (PHB and PHBV) the release of ametryn was by diffusion processes due to anomalous transport (governed by diffusion and relaxation of the polymer chains), which did not follow Fick's laws of diffusion. The results presented in this paper are promising, in view of the successful encapsulation of ametryn in PHB or PHBV polymer microparticles, and indications that this system may help reduce the impacts caused by the herbicide, making it an environmentally safer alternative.
  Journal of hazardous materials 02/2011; 186(2-3):1645-51. · 4.14 Impact Factor
• Article: Research and extension in Environmental Engineering at CREUPI: History and trends

  Gerson de Araújo Medeiros, Gilberto José Hussar, Rogéria Maria Alve de Almeida, André Luiz Paradela, Vasco Luiz Altafin, Celso Henrique Zuppi da Conceição, Rosana Maria Alberici, Nirlei Maria Oliveira, Paulo Sergio Tonello, Carlos Antonio Centurion Maciel, Fábio Augusto Gomes Vieira Reis, Marcelo Della Mura Jannini, Maristela Dellalibera Reis Piccinini, Delbin João, Mônica Luri Giboshi
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  ABSTRACT: CREUPI – Centro Regional Universitário de Espírito Santo do Pinhal established its first Environmental Engineering course in February 2000. Since then and despite its recent creation, our teachers and students have become increasingly involved in research and extension-related activities, which has resulted not only in the steadily growing participation of the course in scientific and technical events, but also in services rendered by the course to the community. The main purpose of this article is to report on the course’s research and extension activities and to outline its future trends. The research and extension activities of our environmental engineering course have been backed by the university’s laboratories of Microbiology, Biotechnology, Limnology and Soil, and have focused on issues relating to rural environments, such as the treatment of water and effluents from agriculture, the reuse of industrial residues in agriculture, the recycling of residues, environmental impacts, and the microbiological quality of water in urban and rural environments. The creation of the Freshwater Project in our extension course has introduced a new approach, which involves activities of extension and environmental education with joint community participation.
  Engenharia Ambiental : Pesquisa e Tecnologia. 01/2004;