Design of a nanostructured mucoadhesive system containing curcumin for buccal application : from physicochemical to biological aspects

Mucoadhesive nanostructured systems comprising poloxamer 407 and Carbopol 974P® have already demonstrated good mucoadhesion, as well as improved mechanical and rheological properties. Curcumin displays excellent biological activity, mainly in oral squamous cancer; however, its physicochemical characteristics hinder its application. Therefore, the aim of this study was to develop nanostructured formulations containing curcumin for oral cancer therapy. The photophysical interactions between curcumin and the formulations were elucidated by incorporation kinetics and location studies. They revealed that the drug was quickly incorporated and located in the hydrophobic portion of nanometer-sized polymeric micelles. Moreover, the systems displayed plastic behavior with rheopexy characteristics at 37 °C, viscoelastic properties and a gelation temperature of 36 °C, which ensures increased retention after application in the oral cavity. The mucoadhesion results confirmed the previous findings with the nanostructured systems showing a residence time of 20 min in porcine oral mucosa under flow system conditions. Curcumin was released after 8 h and could permeate through the porcine oral mucosa. Cytotoxicity testing revealed that the formulations were selective to cancer cells over healthy cells. Therefore, these systems could improve the physicochemical characteristics of curcumin by providing improved release and permeation, while selectivity targeting cancer cells

Waste material of propolis as a film forming agent intended to modify the metronidazole release: preparation and characterization

Metronidazole is an antimicrobial agent utilized for the treatment of protozoa and anaerobic bacteria infections. Many times, it is necessary to modify the metronidazole release, and the development of modified release systems may be suggested. In this study, we are able to investigate the use of the residue normally thrown out from the preparation of propolis extracts (BP) as strategy to modify the metronidazole release. We prepared films containing polymeric adjuvant (gelatin or ethylcellulose) and metronidazole, by solvent casting method. Density, mechanical properties, water vapor permeability (WVP), moisture uptake capacity (MUC), thermogravimetry, differential scanning calorimetry, Fourier transform infrared spectroscopy (FT-IR), and in vitro metronidazole release were investigated. Thickness and density of the preparations indicated that the compounds were homogeneously dispersed throughout. Mechanical properties were influenced by film composition. Films containing gelatin showed higher resistance to stress while those containing ethylcellulose presented greater flexibility. The greater the adjuvant concentrations lower the resistance to rupture and the elasticity, but higher MUC and WVP of formulations. FT-IR tests suggested interactions between BP and the adjuvants. Films were capable to protect the metronidazole and changed its release profile. BP films are of great practical importance constituting a novel strategy to modify the metronidazole release

Chemical Industry: Recent Developments, Problems And Opportunities [indústria Química: Evolução Recente, Problemas E Oportunidades]

Chemical industry underwent a significant upturn in the past few years. In Brazil, the position of this industry has been continuously strengthened as the second largest industrial sector. Current circumstances are discussed, especially the need for increased innovation, the impacts of nanotechnology, biotechnology and information technologies. Some misconceptions on the Brazilian chemical industry are criticized and recent improvements are described, including those related to environmental protection, to conclude that its prospects are very good, considering both the availability of basic raw materials (oil, natural gas, agribusiness products and minerals), the growing demand and increased competitiveness.30614131419Wongtschowski, P., (2002) Industria Química: Risco e Oportunidades, , 2a ed, Edgar Blucher: São PauloMiron, M.V.G., Cavalcanti, F.C.B., Wongtschowski, P., (2005) Quim. Nova, 28 (SUPL.), pp. S86Politzer, K., (2005) Quim. Nova, 28 (SUPL.), pp. S76Oliveira, N.B., (2005) Quim. Nova, 28 (SUPL.), pp. S79Facts and FiguresChem. Eng. News 2006, 84 (28), 36http://www.amrresearch.com/Content/View.asp?pmillid=20086, acessada em Fevereiro 2007Technology Vision 2020 - The U.S. Chemical Industry. American Chemical Society, American Institute of Chemical Engineers, Chemical Manufacturers Association, Council for Chemical Research, Synthetic Organic Chemical Manufacturers Association, 2002http://www.chemconference.com/events/GlobalOutlook07/index.php? eventsfolder=GlobalOutlook07&menuTitle= The%203rd%20Annual%20Chemical%20Industry%20Global %20Outlook%202007, acessada em Fevereiro 2007http://www.southerncompany.com/gapower/grc/pdf/chemical/4_growth.pdf, acessada em Fevereiro 2007http://www.finnfacts.com/english/company/chemical.html, acessada em Fevereiro 2007Storck, W.J., (2006) Chem. Eng. News, 84 (10), p. 46http://www.uic.fr/us/actualite02-c3.htm, acessada em Fevereiro 2007World Chemical OutlookChem. Eng. News 2007, 85 (2), 13http://www.abiquim.org.br/conteudo.asp?princ=ain, acessada em Fevereiro 2007http://www.abiquim.org.br/conteudo.asp?princ=ain&pag=estat, acessada em Fevereiro 2007http://www.desenvolvimento.gov.br/arquivo/ascom/imprensa/ 20060404balancoPITCE.pdf, acessada em Fevereiro 2007http://www.abiquif.org.br/br/principal.htm, acessada em Fevereiro 2007www.ache.com.br/scripts/phytomedica/lancamentos.asp, acessada em Fevereiro 2007http://www2.cristalia.com.br:8080/cristalia/site/imprensa/artigo_in.jsp? id=75&typeid=1, acessada em Fevereiro 2007Suppes, G.S., (2005) Appl. Catal., A, 281, p. 225Zhao, Q.Q., Boxman, A., Chowdhry, U., (2003) J. Nanoparticle Res, 5, p. 567http://www.chemicalvision2020.org/, acessada em Fevereiro 2007http://www.chemicalvision2020.org/nanotechnology.html, acessada em Fevereiro 2007http://www.biphorpigments.com, acessada em Fevereiro 2007Rosseto, R., Santos, A.C.M., Galembeck, F., (2006) J. Braz. Chem. Soc, 17, p. 1465McCoy, M., (2006) Chem.Eng. News, 84 (2), p. 32Nota em, (2006) Chem. Eng. News, 84 (11), p. 22http://www.lisina.com.br/noticias/noticias_destaque.asp?Acao= Noticia&ea_id=292, acessada em Fevereiro 2007http://news.bbc.co.uk/1/hi/sci/tech/889951.stm, acessada em Fevereiro 2007http://www.uspto.gov/, acessada em Fevereiro 2007http://www.espacenet.com/, acessada em Fevereiro 2007Hoffman, A.J., (1999) Academy of Management Journal, 42 (4), p. 351http://www.rachelcarson.org/, acessada em Fevereiro 2007www.unioncarbide.com/bhopal, acessada em Fevereiro 2007http://www.abiquim.org.br/conteudo.asp?princ=atu, acessada em Fevereiro 2007http://www.reachlegislation.com/, acessada em Fevereiro 2007http://news.bbc.co.uk/2/hi/europe/4446880.stm, acessada em Fevereiro 200

Condicionamento fisiológico de sementes de berinjela Priming of eggplant seeds

A pesquisa objetivou avaliar métodos de condicionamento fisiológico de sementes de berinjela (Solanum melongena L.). Para tanto, sementes de três lotes, cultivar Napoli, foram condicionadas entre papel toalha com 30, 60 e 90 mL de água a 15, 20 e 25 ºC e com soluções a -0,5, -1,0, -1,5 e -2,5 MPa de PEG 6000 a 20 ºC e, em seguida, secadas a 30 &deg;C até atingirem teores de água similares aos originais. Sementes sem (testemunha) e com condicionamento foram avaliadas quanto ao teor de água, à germinação e ao vigor (velocidade de germinação, envelhecimento acelerado, deterioração controlada e condutividade elétrica). Os tratamentos de maior desempenho (20 &deg;C, 90 mL de água ou PEG -0,5 MPa) foram novamente aplicados às sementes que, juntamente com as da testemunha, foram armazenadas e avaliadas pelos mesmos testes aos 0, 60 e 120 dias. Há a possibilidade de condicionar fisiologicamente as sementes de berinjela, a 20 ºC, entre papel toalha, com água ou com solução -0,5 MPa de PEG 6000, seguido de secagem.<br>The objective of this research was to study priming methods of eggplant seeds. Three seed lots of the Napoli cultivar were conditioned between paper towels )with 30, 60 and 90 mL of water at 15, 20 and 25 &deg;C), and with PEG solutions (-0.5, -1.0, -1.5, and -2.5 MPa at 20 &deg;C); following that, seeds were dried at 30 &deg;C until water contents similar to original ones. The unconditioned (check) and conditioned seeds were evaluated in relation to water content, germination and vigor (speed of germination, accelerated aging, controlled deterioration and electrical conductivity). The most effective treatments (20 &deg;C, with water or -0.5 MPa PEG) were again applied to other samples of same seeds which, together with the those of the check, were stored and evaluated through the same tests at 0, 60 and 120 days. Results showed that there is the possibility of conditioning eggplant seeds at 20 &deg;C, between paper towels, with water or with solution of -0.5 MPa PEG 6000, followed by drying