Banca de DEFESA: André Luiz Teixeira

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : André Luiz Teixeira
DATE: 30/08/2022
TIME: 09:00
LOCAL: Sala Multiuso IB/GEM FT 55/8
TITLE:

Interaction between dirhodium(II) tetraacetate and PAMAM dendrimer grafted onto magnetite nanoparticles: Effects on magnetic properties and treatment of breast cancer cells

KEY WORDS:

Drug delivery; magnetic nanoparticle; PAMAM dendrimer coating; Tetrakis-DiRhodium(II) Acetate complex.

PAGES: 105
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

This study reports the success of the fabrication and characterization of a novel magnetic nanocarrier based on association of magnetite nanoparticles with poly(amidoamine) (PAMAM) dendrimers loading dirhodium(II) tetraacetate complex (DiRh(II)). Interaction between PAMAM dendrimers and DiRh(II) and its effects on magnetic properties and biological activities in 4T1 and MCF7 cancer cells were investigated. Magnetite spinel phase is confirmed via x-ray diffraction (XRD) and Raman spectroscopy data analysis. Magnetite mean crystallite size of 9.5 ± 0.3 nm is assessed from XRD data, which is close to values obtained via dynamic light scattering (DLS) and transmission electron microscopy micrographs. Our findings strongly suggest that Rh(II) ions interact with lone electron pairs of nitrogen atoms in amide-II and primary amines of PAMAM surface-terminated moieties. Magnetization data indicate that the presence of DiRh(II) attached to PAMAM dendrimer leads to strong weakening of magnetic dipole-dipole interaction in ATPS- and ATPS+PAMAM coated magnetite nanoparticles. In vitro assays performed on 4T1 and MCF7 cells show that both the DiRh(II) complex and MAPP systems do not show statistically significant cytotoxicity in the range of DirRh(II) concentration studied. On the other hand, the noanostructured MAPPRh and PPDiRh(II) systems show high cytotoxic activity in both cell lines, with the IC50 observed for the MAPPRh system being 15 times lower than that observed for the PPDiRh(II) system. Studies of the internalization profile of nanostructured systems in 4T1 and MPF7 cells show that for both cell lines the internalization of the MAPPRh and PPDiRh(II) systems was much higher than that observed for the MAPP system. Finally, apoptosis is identified as the main mechanism of cell death after treatment with the MAPPRh and PPDiRh(II) systems. This result is more pronounced for 4T1 cells when compared to MCF7 cells.

BANKING MEMBERS:
Externo à Instituição - MARTIN SCHWELLBERGER BARBOSA - UFG
Externo à Instituição - DENILSON RABELO - UFG
Externo à Instituição - CELIA MARIA DE ALMEIDA SOARES - UFG
Externo ao Programa - 1764408 - PAULO EDUARDO NARCIZO DE SOUZA
Externo ao Programa - 1210273 - SEBASTIAO WILLIAM DA SILVA