2025-03-312025-04-242029-11-292025-04-242024-11-14Isadora Cruvinel, FRIGO. Síntese de nanopartículas de quitosana como sistema carreador de liberação prolongada de putrescina. 2024.37 f. Dissertação (Mestrado em Biotecnologia) - Universidade Federal de Alfenas, Alfenas, MG, 2024.https://repositorio.unifal-mg.edu.br/handle/123456789/2716The present study addresses the synthesis of chitosan nanoparticles, evolving their application as a putrescine transporter. The use of chitosan can be an economical and sustainable alternative in Brazil, considering the fact that the country has an abundant number of fishing industries and that crustacean shells, a source of chitin, a substance that after undergoing deacetylation turns into chitosan, are discarded for the most part. The synthesis encompassed four different concentrations of chitosan 0.42, 0.84, 1.25 and 2.5 mg mL-1, with the cross-linking method being used to improve the stability and effectiveness of the resulting nanoparticles. The solutions containing chitosan were prepared in water acidified with acetic acid containing Tween 80. Subsequently, a chloroform solution was used and added to this putrescine phase. The characterization was carried out using the Polydispersity Index and particle size. The release tests were carried out in three different media: acid solution, methanol and phosphate released solution pH 5. The concentration of 0.42 mg mL-1 of chitosan has a smaller size and better encapsulation with the highest concentration of putrescine (3mM). The synthesized nanoparticle presents acceptable characteristics considering size and Polydispersity Index. Studies show that prolonged release generates lower financial costs, since its use is reduced, and its action time is long. In the prolonged release study, the pH 5 vitamin phosphate medium favors the release of the largest quantity of nanoparticles, with no significant variation between times of 6 to 72 hours. It was possible to obtain chitosan nanoparticles with putrescine.application/pdfAcesso EmbargadoBioestimulanteNanotecnologiaSustentabilidadeCIENCIAS BIOLOGICAS::BIOQUIMICADissertaçãoSantos Filho, Plinio Rodrigues Dos