Microencapsulação do pesticida cipermetrina em blendas de P(3HB/PCL): caracterização e ensaio de liberação in vitro
Microencapsulation of cypermethrin pesticide in P(3HB)/PCL blends: characterization and in vitro controlled release
Dall’Agnol, Evana Cássia; Suave, Jaqueline; Meier, Marcia Margarete; Soldi, Valdir; Silva, Denise Abatti Kasper; Pezzin, Ana Paula Testa
http://dx.doi.org/10.1590/0104-1428.0343
Polímeros: Ciência e Tecnologia, vol.26, n3, p.269-276, 2016
Resumo
A aplicação de polímeros biodegradáveis para encapsular pesticidas é uma estratégia que permite, a partir de diferentes proporções entre os polímeros, modificar o perfil de liberação do agente. Este trabalho avaliou a liberação controlada do pesticida cipermetrina encapsulado em microesferas de blendas de P(3HB)/PCL (100/0, 0/100, 97/03, 95/05, 90/10, 80/20 e 70/30) obtidas pelo método de emulsificação-evaporação do solvente. As imagens de microscopia eletrônica de varredura revelam a forte influência da PCL na porosidade das microesferas. As análises de infravermelho mostraram a presença do pesticida em todas as composições de polímeros avaliadas. O ensaio de liberação de cipermetrina sugere que, no intervalo de 4 horas, o teor de cipermetrina liberada é dependente da composição das blendas utilizadas. As microesferas de PHB e blendas com menores teores de PCL, 97/03 e 95/05 liberaram 75% a 85% enquanto a composição 70/30 liberou 100% de cipermetrina.
Palavras-chave
polímeros biodegradáveis, blendas, microencapsulação.
Abstract
This work evaluated the controlled release of cypermethrin pesticide loaded in microspheres of P(3HB)/PCL blends obtained by emulsion-evaporation method. SEM analysis revealed a strong influence of PCL on the porosity of the microspheres. The infrared spectra showed the presence of pesticide in all polymer compositon evaluated. DSC curves showed that with higher content of PCL, decreased the crystallinity degree of polymers, resulting in a faster release of the pesticide. The release assay of cypermethrin suggests that within an interval of four hours the amount of pesticide released varies depending on the composition of the blends.
Keywords
biodegradable polymers, blends, microencapsulation.
References
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35. Zhu, Y., An, X., Li, S., & Yu, S. (2009). Nanoencapsulation of β-Cypermethrin by complex coacervation in a microemulsion. Journal of Surfactants and Detergents, 12(4), 305-311. http://dx.doi.org/10.1007/s11743-009-1124-8.
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41. Tsuji, H., & Ikada, Y. (1996). Blends of aliphatic polyesters. I. Physical properties and morphologies of solution-cast blends from poly(DL-lactide) and poly(ε-caprolactone). Journal of Applied Science, 60(13), 2367-2375. http://dx.doi.org/10.1002/(SICI)1097-4628(19960627)60:13<2367::AID-APP8>3.0.CO;2-C.
2. Ranade, V. V., & Hollinger, M. A. (2004). Drug delivery systems (2nd ed.). Boca Raton: CRC Press.
3. El Bahri, Z., & Taverdet, J. L. (2007). Elaboration and characterisation of microparticles loaded by pesticide model. Powder Technology, 172(1), 30-40. http://dx.doi.org/10.1016/j.powtec.2006.10.036.
4. Kulkarni, A. R., Soppimath, K. S., Aminabhavi, T. M., Dave, A. M., & Mehta, M. H. (2000). Glutaraldehyde crosslinked sodium alginate beads containing liquid pesticide for soil application. Journal of Controlled Release, 63(1-2), 97-105. http://dx.doi.org/10.1016/S0168-3659(99)00176-5. PMid:10640583.
5. Scher, H. B. (2009). Controlled-release delivery systems for pesticides. New York: Marcel Dekker.
6. Junyaprasert, V. B., Mitrevej, A., Sinchaipanid, N., Boonme, P., & Wurster, D. E. (2001). Effect of process variables on the microencapsulation of vitamin A palmitate by gelatin-acacia coacervation. Drug Development and Industrial Pharmacy, 27(6), 561-566. http://dx.doi.org/10.1081/DDC-100105181. PMid:11548863.
7. Karasulu, E., Karasulu, H. Y., Ertan, G., Kirilmaz, L., & Güneri, T. (2003). Extended release lipophilic indomethacin microspheres: formulation factors and mathematical equations fitted drug release rates. European Journal of Pharmaceutical Sciences, 19(2-3), 99-104. http://dx.doi.org/10.1016/S0928-0987(03)00048-4. PMid:12791411.
8. Oneda, F., & Ré, M. I. (2003). The effect of formulation variables on the dissolution and physical properties of spray-dried microspheres containing organic salts. Powder Technology, 130(1-3), 377-384. http://dx.doi.org/10.1016/S0032-5910(02)00239-5.
9. Hirech, K., Payan, S., Carnelle, G., Brujes, L., & Legrand, J. (2003). Microencapsulation of an Insecticide by Interfacial Polymerization. Powder Technology, 130(1-3), 324-330. http://dx.doi.org/10.1016/S0032-5910(02)00211-5.
10. El Bahri, Z., & Taverdet, J. L. (2005). Optimization of an herbicide release from ethylcellulose microspheres. Polymer Bulletin, 54(4-5), 353-363. http://dx.doi.org/10.1007/s00289-005-0385-2.
11. Ryszka, F., Dolinska, B., & Waleczek, D. (2002). Sustained release and biological availability of dalarelin from the biodegradable coacervate microcapsules. Farmaco, 57(12), 985-988. http://dx.doi.org/10.1016/S0014-827X(02)01295-8. PMid:12564472.
12. Fernández-Pérez, M., González-Pradas, E., Ureña-Amate, M. D., Wilkins, R. M., & Lindup, I. (1998). Controlled release of imidacloprid from a lignin matrix: water release kinetics and soil mobility study. Journal of Agricultural and Food Chemistry, 46(9), 3828-3834. http://dx.doi.org/10.1021/jf980286f.
13. Gassner, F., & Owen, A. J. (1994). Physical properties of poly(β-hydroxybutyrate)-poly(ε-caprolactone) blends. Polymer Report, 35(10), 2233-2236. http://dx.doi.org/10.1016/0032-3861(94)90258-5.
14. Wessler, K., Nishida, M. H., Silva, J. Jr, Pezzin, A. P. T., & Pezzin, S. H. (2006). Thermal Properties and Morphology of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) with Poly(Caprolactone Triol) Mixtures. Macromolecular Symposia, 245(1), 161-165. http://dx.doi.org/10.1002/masy.200651322.
15. Casarin, S. A., Agnelli, J. A. M., Malmonge, S. M., & Francisco, R. (2013). Blendas PHB/copoliésteres biodegradáveis: biodegradação em solo. Polímeros: Ciência e Tecnologia, 23(1), 115-122. http://dx.doi.org/10.1590/S0104-14282013005000003.
16. Brydson, J. A. (1999). Plastics materials (7th ed.). London: British Library Cataloguing in Publication Data.
17. Anderson, A. J., & Dawes, E. A. (1990). Occurrence, metabolism, metabolic role, and industrial uses of bacterial polyhydroxyalkanoates. Microbiological Reviews, 54(4), 450-472. PMid:2087222.
18. Duarte, M. A. T., Hugen, R. G., Martins, E. S., Pezzin, A. P. T., & Pezzin, S. H. (2006). Thermal and mechanical behavior of injection molded Poly (3-hydroxybutyrate)/Poly (epsilon-caprolactone) blends. Materials Research, 9(1), 25-28. http://dx.doi.org/10.1590/S1516-14392006000100006.
19. Meier, M. M., Kanis, L. A., Lima, J. C., Pires, A. T. N., & Soldi, V. (2004). Poly(caprolactone triol) as plasticizer agent for cellulose acetate films: influence of the preparation procedure and plasticizer content on the physico-chemical properties. Polymers for Advanced Technologies, 15(10), 593-600. http://dx.doi.org/10.1002/pat.517.
20. Vogelsanger, N., Furlan, S. A., Schneider, A. L. S., Pires, A. T. N., Pezzin, S. H., & Pezzin, A. P. T. (2004). Filmes de P(3HB) e PCL: acompanhamento da biodegradação em solo por propriedades térmicas e morfológicas. Revista Matéria, 9, 370-377. Recuperado em 06 de julho de 2015, de http://www.materia.coppe.ufrj.br/sarra/artigos/artigo10621
21. Rosa, D. S., Chui, Q. S. H., Pantano , R. Fo., & Agnelli, J. A. M. (2002). Avaliação da Biodegradação de Poli- β -(Hidroxibutirato), Poli- β -(Hidroxibutirato-co-valerato) e Poli- ε -(caprolactona) em Solo Compostado. Polímeros: Ciência e Tecnologia, 12(4), 311-317. http://dx.doi.org/10.1590/S0104-14282002000400015.
22. Shalaby, W. S., & Burg, K. J. L. (2004). Absorbable and biodegradable polymers. Boca Raton: CRC Press.
23. Vogelsanger, N., Formolo, M. C., Pezzin, A. P. T., Schneider, A. L. S., Furlan, S. A., Bernardo, H. P., Pezzin, S. H., Pires, A. T. N. & Duek, E. A. R. (2003). Blendas biodegradáveis de poli(3-hidroxibutirato)/poli(e-caprolactona): obtenção e estudo da miscibilidade. Materials Research, 6(3), 359-365. http://dx.doi.org/10.1590/S1516-14392003000300010.
24. Siegfried, B. D. (1993). Comparative toxicity of pyrethroid insecticides to terrestrial and aquatic insects. Environmental Toxicology and Chemistry, 12(9), 1683-1689. http://dx.doi.org/10.1002/etc.5620120917.
25. Campos, A., Marconato, J. C., & Martins-Franchetti, S. M. (2012). The influence of soil and landfill leachate microorganisms in the degradation of PVC/PCL films cast from DMF. Polímeros: Ciência e Tecnologia, 22(3), 220-227. http://dx.doi.org/10.1590/S0104-14282012005000029.
26. Rocha, M. C. G., & Moraes, L. R. C. (2015). Low Density Polyethylene (LDPE) blends based on Poly(3-Hydroxi-Butyrate) (PHB) and Guar Gum (GG) biodegradable polymers. Polímeros: Ciência e Tecnologia, 25(1), 42-48. http://dx.doi.org/10.1590/0104-1428.1495.
27. Jones, D. (1995). Environmental fate of Cypermethrin: environmental monitoring and pest management. Sacramento: Department of Pesticide Regulation.
28. Clarke, E. E., Levy, L. S., Spurgeon, A., & Calvert, I. A. (1997). The problems associated with pesticide use by irrigation workers in Ghana. Occupational Medicine, 47(5), 301-308. http://dx.doi.org/10.1093/occmed/47.5.301. PMid:9302813.
29. Beaumont, P. (1993). Pesticides policies and people: a guide to the issues. London: Pesticides Trust.
30. Freidberg, S. (2003). Cleaning up down South: supermarkets, ethical trade and African horticulture. Social & Cultural Geography, 4(1), 27-43. http://dx.doi.org/10.1080/1464936032000049298.
31. Pretty, J., & Hine, R. (2005). The pesticide detox: towards a more sustainable agricultura. London: Earthscan.
32. Singh, A. K., Tiwari, M. N., & Prakash, O. (2012). A current review of cypermethrin-induced neurotoxicity and nigrostriatal dopaminergic neurodegeneration. Current Neuropharmacology, 10(1), 64-71. http://dx.doi.org/10.2174/157015912799362779. PMid:22942879.
33. Xia, C.-M., Zhou, Y.-F., Nie, W.-Y., Song, L.-Y., Dai, M.-D., Xu, X.-L., & Wang, Z. (2012). Fabrication and characterization of cypermethrin nanocapsules in miniemulsion polymerization system. Journal of Applied Polymer Science, 126(6), 1859-1866. http://dx.doi.org/10.1002/app.36866.
34. Bang, S. H., Hwang, I. C., Yu, Y. M., Kwon, H. R., Kim, D. H. & Park, H. J. (2011). Influence of chitosan coating on the liposomal surface on physicochemical properties and the release profile of nanocarrier systems. Journal of Microencapsulation, 28(7), 595-604. http://dx.doi.org/10.3109/02652048.2011.557748.
35. Zhu, Y., An, X., Li, S., & Yu, S. (2009). Nanoencapsulation of β-Cypermethrin by complex coacervation in a microemulsion. Journal of Surfactants and Detergents, 12(4), 305-311. http://dx.doi.org/10.1007/s11743-009-1124-8.
36. Zeng, H., Li, X., Zhang, G., & Dong, J. (2008). Preparation and characterization of beta Cypermethrin nanosuspensions by diluting O/W microemulsions. Journal of Dispersion Science and Technology, 29(3), 358-361. http://dx.doi.org/10.1080/01932690701716085.
37. Suave, J., Dall’Agnol, E. C., Pezzin, A. P. T., Meier, M. M., & Silva, D. A. K. (2010). Biodegradable microspheres of poly(3-hydroxybutyrate)/poly(ε-caprolactone) loaded with malathion pesticide: preparation, characterization, and in vitro controlled release testing. Journal of Applied Polymer Science, 117(6), 3419-3427. http://dx.doi.org/10.1002/app.32082.
38. Stuart, M. A. C., Huck, W. T. S., Genzer, J., Müller, M., Ober, C., Stamm, M., Sukhorukov, G. B., Szleifer, I., Tsukruk, V. V., Urban, M., Winnik, F., Zauscher, S., Luzinov, I., & Minko, S. (2010). Emerging applications of stimuli-responsive polymer materials. Nature Materials, 9(2), 101-113. http://dx.doi.org/10.1038/nmat2614. PMid:20094081.
39. Quental, A. C., & Felisberti, M. I. (2001). Comportamento térmico e morfológico do poli(hidroxibutirato)-PHB. In Anais do 6º Congresso Brasileiro de Polímeros (pp. 1260-1263). Gramado: Associação Brasileira de Polímeros.
40. Rosa, D. S., Penteado, D. F., & Calil, M. R. (2000). Propriedades térmicas e biodegradabilidade de PCL e PHB em um pool de fungos. Revista de Ciência & Tecnologia, 15(8), 75-80. Recuperado em 06 de julho de 2015, de http://www.unimep.br/phpg/editora/revistaspdf/rct15art09.pdf
41. Tsuji, H., & Ikada, Y. (1996). Blends of aliphatic polyesters. I. Physical properties and morphologies of solution-cast blends from poly(DL-lactide) and poly(ε-caprolactone). Journal of Applied Science, 60(13), 2367-2375. http://dx.doi.org/10.1002/(SICI)1097-4628(19960627)60:13<2367::AID-APP8>3.0.CO;2-C.