Banca de QUALIFICAÇÃO: ELTON MARLON DE ARAUJO LIMA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ELTON MARLON DE ARAUJO LIMA
DATE: 15/06/2023
LOCAL: Programa de Pós-Graduação em Ciência de Materiais
TITLE:

DEVELOPMENT OF A MAGNETIC NANOCOMPOSITE BASED ON IRON OXIDE AND CONDUCTIVE POLYMER (γ-Fe₂O₃-POLYTHIOPHENE) AS A THERAPEUTIC PLATFORM AGAINST TEGUMENTARY LEISHMANIASIS

KEY WORDS:

Magnetic nanocomposite; cutaneous leishmaniasis; nanotechnology.

PAGES: 128
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

In this work, we present a new nanobiotechnological therapeutic platform based on nanocomposites of magnetic iron oxide (γ-Fe₂O₃) and a conducting polymer (Polythiophene - PTh), which was developed to overcome the limits of conventional treatment of tegumentary leishmaniasis. The Fenton reaction was used to synthesize the γ-Fe₂O₃/PTh hybrid magnetic nanocomposite, which was then characterized by UV-Vis, FTIR, SEM-EDS, magnetization and particle size measurements. The cytocompatibility profile of the nanocomposite with mammalian cells and human erythrocytes was investigated, as well as its anti-Leishmania potential against two species that cause cutaneous leishmaniasis (L. amazonensis and L. braziliensis) in two stages of development: promastigotes (present in hosts invertebrates) and axenic amastigote (its form in vertebrate hosts). The γ-Fe₂O₃/PTh nanocomposite obtained had an average size of 41 nm, and the presence of the PTh coating was confirmed by spectroscopic measurements. The nanocomposite showed superparamagnetic behavior with magnetization saturation of 15.7 emu/g at room temperature. In cytocompatibility studies, the γ-Fe₂O₃/PTh nanocomposite did not reduce the cell viability of the strains tested (fibroblasts, Vero cells and macrophages). It was also possible to confirm that the γ-Fe₂O₃/PTh nanocomposite showed a low capacity to cause rupture in human red blood cells of different phenotypes, indicating good hemocompatibility. Overall, the in vitro cytotoxicity studies showed a promising cytotoxicological profile, allowing the possibility of using the γ-Fe₂O₃/PTh nanocomposite in medicinal formulations. Finally, it was also possible to show that the γ-Fe₂O₃/PTh nanocomposite significantly inhibits the growth of the promastigote forms of L. amazonensis (IC₅₀ = 117.63 μg/mL), while inhibiting the axenic amastigotes forms of L. braziliensis and L. amazonensis. It was verified that the γ-Fe₂O₃/PTh nanocomposite has the capacity to cause more intense mitochondrial membrane depolarization in the promastigote forms of L. amazonensis. Our results indicate that the γ-Fe₂O₃/PTh nanocomposite emerges as a new nanobiotechnological product that offers an opportunity for advances in the treatment of neglected infectious diseases, such as leishmaniasis, due to the adequate combination of good efficacy and greater selectivity for the parasite than for the host cell (macrophage).

COMMITTEE MEMBERS:
Externo à Instituição - ARNOBIO ANTONIO DA SILVA JUNIOR - UFRN
Presidente - 2199290 - BEATE SAEGESSER SANTOS
Externo à Instituição - FABIO ROCHA FORMIGA - UPE