Efeito da modificação química na solubilidade e intumescimento de microesferas à base de goma do cajueiro carboximetilada e quitosana
Effect of chemical modification on the solubility and swelling of microspheres based on carboxymethyl cashew gum and chitosan
Monteiro, Aliny Abreu de Sousa; Richter, Ana Rosa; Maciel, Jeanny da Silva; Feitosa, Judith Pessoa Andrade; Paula, Haroldo César Beserra; Paula, Regina Célia Monteiro de
http://dx.doi.org/10.1590/0104-1428.1779
Polímeros: Ciência e Tecnologia, vol.25, nSuppl, p.31-39, 2015
Resumo
Esferas de goma do cajueiro carboximetilada e quitosana foram produzidas via complexação polieletrolítica. As esferas foram modificadas quimicamente de modo a obter-se sistemas estáveis em meio ácido e que apresentassem uma resposta de intumescimento diferenciado frente à variação de pH. As esferas foram modificadas por reacetilação da quitosana e por reticulação com epicloridrina, glutaraldeído e genipina. As esferas reticuladas foram caracterizadas por meio de técnicas como: espectroscopia de absorção no infravermelho, análise termogravimétrica, microscopia eletrônica de varredura e quanto à solubilidade em pH 1,2 e ao intumescimento. As esferas de goma do cajueiro carboximetilada e quitosana reacetilada, e as esferas reticuladas com epicloridrina apresentaram baixa resistência à dissolução em pH 1,2. Entretanto, as esferas reticuladas com glutaraldeído e genipina apresentaram resistência à dissolução e baixo coeficiente de difusão. As esferas reticuladas com genipina apresentaram um grau de intumescimento maior do que as esferas reticuladas com glutaraldeído nas concentrações de 3% e 5% (massa/volume). As esferas reticuladas com genipina apresentaram intumescimento responsivo à variação de pH e estabilidade em pH 1,2, indicando que esses sistemas possuem potencial para uso em sistemas de liberação controlada de fármacos por via oral.
Palavras-chave
goma do cajueiro, carboximetilação, quitosana, reticulação.
Abstract
Chitosan/carboxymethylated cashew gum beads were produced via polyelectrolytic complexation. The beads were chemically modified to achieve stable acidic medium and to provide a swelling response in different pH. The beads were modified by chitosan reacetylation and by crosslinking with epichlorohydrin, glutaraldehyde and genipin. The beads were characterized by techniques such as: infrared spectroscopy, thermogravimetry, scanning electron microscopy and regarding their solubility at pH 1.2 and swelling. The beads of carboxymethyl cashew gum and reacetylated chitosan and those crosslinked with epichlorohydrin had low resistances to dissolution at pH 1.2. However, the beads crosslinked with glutaraldehyde and genipin showed resistance to dissolution along with low diffusion coefficients. Moreover, beads crosslinked with genipin presented a higher degree of swelling than beads crosslinked with glutaraldehyde at concentrations of 3% and 5% (weight/volume). Beads crosslinked with genipin presented responsive behavior to pH variation and stability at pH 1.2, indicating that these systems have potential for use in controlled drug delivery systems for oral administration.
Keywords
cashew gum, carboxymethylation, chitosan, crosslinking.
References
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2. Kilicarslan, M., Gumustas, M., Yildiz, S., & Baykara, T. (2014). Preparation and characterization of chitosan-based spray-dried microparticles for the delivery of clindamycin phosphate to periodontal pockets. Current Drug Delivery, 11(1), 98-111. http://dx.doi.org/10.2174/15672018113109990055. PMid:23947602.
3. Zhao, L., Li, N., Wang, K., Shi, C., Zhang, L., & Luan, Y. (2014). A review of polypeptide-based polymersomes. Biomaterials, 35(4), 1284-1301. http://dx.doi.org/10.1016/j.biomaterials.2013.10.063. PMid:24211077.
4. Berger, J., Reist, M., Mayer, J. M., Felt, O., Peppas, N. A., & Gurny, R. (2004). Structure and interactions in covalently and ionically crosslinked chitosan hydrogels for biomedical applications. European Journal of Pharmaceutics and Biopharmaceutics, 57(1), 19-34. http://dx.doi.org/10.1016/S0939-6411(03)00161-9. PMid:14729078.
5. Silva, M. A., Bierhalz, A. C. K., & Kieckbusch, T. G. (2009). Alginate and pectin composite films crosslinked with Ca2+ ions: Effects of the plasticizer concentration. Carbohydrate Polymers, 77(4), 736-742. http://dx.doi.org/10.1016/j.carbpol.2009.02.014.
6. Martins, A. F., de Oliveira, D. M., Pereira, A. G. B., Rubira, A. F., & Muniz, E. C. (2012). Chitosan/TPP microparticles obtained by microemulsion method applied in controlled release of heparin. International Journal of Biological Macromolecules, 51(5), 1127-1133. http://dx.doi.org/10.1016/j.ijbiomac.2012.08.032. PMid:22975304.
7. Chung, T., Chang, C., & Ho, C. (2011). Incorporating chitosan (CS) and TPP into silk fibroin (SF) in fabricating spray-dried microparticles prolongs the release of a hydrophilic drug. Journal of the Taiwan Institute of Chemical Engineers, 42(4), 592-597. http://dx.doi.org/10.1016/j.jtice.2010.11.003.
8. Silva, D. A., Feitosa, J. P. A., Maciel, J. S., Paula, H. C. B., & de Paula, R. C. M. (2006). Characterization of crosslinked cashew gum derivatives. Carbohydrate Polymers, 66(1), 16-26. http://dx.doi.org/10.1016/j.carbpol.2006.02.021.
9. Maciel, J. S. (2005). Géis de goma do cajueiro e derivados com quitosana: síntese, caracterização e ensaios preliminares em sistemas de liberação de fármacos (Tese de Doutorado). Universidade Federal do Ceará, Fortaleza.
10. Tirtom, V. N., Dinçer, A., Becerik, S., Aydemir, T., & Çelik, A. (2012). Comparative adsorption of Ni(II) and Cd(II) ions on epichlorohydrin crosslinked chitosan-clay composite beads in aqueous solution. Chemical Engineering Journal, 197, 379-386. http://dx.doi.org/10.1016/j.cej.2012.05.059.
11. Rocher, V., Bee, A., Siaugue, J., & Cabuil, V. (2010). Dye removal from aqueous solution by magnetic alginate beads crosslinked with epichlorohydrin. Journal of Hazardous Materials, 178(1-3), 434-439. http://dx.doi.org/10.1016/j.jhazmat.2010.01.100. PMid:20153928.
12. Dash, M., Chiellini, F., Ottenbrite, R. M., & Chiellini, E. (2011). Chitosan: a versatile semi-synthetic polymer in biomedical applications. Progress in Polymer Science, 36(8), 981-1014. http://dx.doi.org/10.1016/j.progpolymsci.2011.02.001.
13. Ramachandran, S., Nandhakumar, S., & Dhanaraju, M. D. (2011). Formulation and characterization of glutaraldehyde cross-linked chitosan biodegradable microspheres loaded with famotidine. Tropical Journal of Pharmaceutical Research, 10(3), 309-316. http://dx.doi.org/10.4314/tjpr.v10i3.13.
14. Nayak, U. Y., Gopal, S., Mutalik, S., Ranjith, A. K., Reddy, M. S., Gupta, P., & Udupa, N. (2009). Glutaraldehyde cross-linked chitosan microspheres for controlled delivery of zidovudine. Journal of Microencapsulation, 26(3), 214-222. http://dx.doi.org/10.1080/02652040802246325. PMid:18819029.
15. Tahtat, D., Mahlous, M., Benamer, S., Khodja, A. N., Oussedik-Oumehdi, H., & Laraba-Djebari, F. (2013). Oral delivery of insulin from alginate/chitosan crosslinked by Glutaraldehyde. International Journal of Biological Macromolecules, 58, 160-168. http://dx.doi.org/10.1016/j.ijbiomac.2013.03.064. PMid:23567292.
16. Silva, D. A., Feitosa, J. P. A., Paula, H. C. B., & Paula, R. C. M. (2009). Synthesis and characterization of cashew gum/acrylic acid nanoparticles. Materials Science and Engineering C, 29(2), 437-441. http://dx.doi.org/10.1016/j.msec.2008.08.029.
17. Feng, H., Zhang, L., & Zhu, C. (2013). Genipin crosslinked ethyl cellulose–chitosan complex microspheres for anti-tuberculosis delivery. Colloids and Surfaces B, Biointerfaces, 103, 530-537. http://dx.doi.org/10.1016/j.colsurfb.2012.11.007. PMid:23266829.
18. Karnchanajindanun, J., Srisa-ard, M., & Baimark, Y. (2011). Genipin-cross-linked chitosan microspheres prepared by a water-in-oil emulsion solvent diffusion method for protein delivery. Carbohydrate Polymers, 85(3), 674-680. http://dx.doi.org/10.1016/j.carbpol.2011.03.035.
19. de Paula, R. C. M., & Rodrigues, J. F. (1995). Compositions and rheological properties of cashew tree gum, the exudate polysaccharide from Anacardium occidentale L. Carbohydrate Polymers, 26(3), 177-181. http://dx.doi.org/10.1016/0144-8617(95)00006-S.
20. de Paula, R. C. M., Heatley, F., & Budd, P. M. (1998). Characterizations of Anarcardium occidentale exudate polysaccharide. Polymer International, 45(1), 27-35. http://dx.doi.org/10.1002/(SICI)1097-0126(199801)45:1<27::AID-PI900>3.0.CO;2-9.
21. Silva, D. A., de Paula, R. C. M., Feitosa, J. P. A., de Brito, A. C. F., Maciel, J. S., & Paula, H. C. B. (2004). Carboxymethylation of cashew tree exudate polysaccharide. Carbohydrate Polymers, 58(2), 163-171. http://dx.doi.org/10.1016/j.carbpol.2004.06.034.
22. Maciel, J. S., Silva, D. A., Paula, H. C. B., & de Paula, R. C. M. (2005). Chitosan/carboxymethyl cashew gum polyelectrolyte complex: synthesis and thermal stability. European Polymer Journal, 41(11), 2726-2733. http://dx.doi.org/10.1016/j.eurpolymj.2005.05.009.
23. Paula, H. C. B., Oliveira, E. F., Abreu, F. O. M. S., & Paula, R. C. M. (2012). Alginate/cashew gum floating bead as a matrix for larvicide release. Materials Science and Engineering C, 32(6), 1421-1427. http://dx.doi.org/10.1016/j.msec.2012.04.021. PMid:24364941.
24. Magalhães, G. A. Jr, Santos, C. M. W., Silva, D. A., Maciel, J. S., Feitosa, J. P. A., Paula, H. C. B., & de Paula, R. C. M. (2009). Microspheres of chitosan/carboxymethyl cashew gum (CH/CMCG): Effect of chitosan molar mass and CMCG degree of substitution on the swelling and BSA release. Carbohydrate Polymers, 77(2), 217-222. http://dx.doi.org/10.1016/j.carbpol.2008.12.037.
25. Moura, E., No., Maciel, J. S., Cunha, P. L. R., Paula, R. C. M., & Feitosa, J. P. A. (2011). Preparations and characterization of a chemically sulfated cashew gum polysaccharide. Journal of the Brazilian Chemical Society, 22(10), 1953-1960. http://dx.doi.org/10.1590/S0103-50532011001000017.
26. Rodrigues, J. F., Paula, R. C. M., & Costa, S. M. O. (1993). Métodos de isolamento de gomas naturais: comparação através da goma do cajueiro (Anacardium Occidentale L.). Polímeros Ciência e Tecnologia, 3(1), 31-36.
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