Banca de DEFESA: GABRIELA MARQUES DE ALBUQUERQUE

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : GABRIELA MARQUES DE ALBUQUERQUE
DATE: 26/07/2024
TIME: 10:00
LOCAL: Programa de Pós-Graduação em Ciência de Materiais
TITLE:

DEVELOPMENT OF MULTIMODAL OPTICAL-PARAMAGNETIC NANOPLATFORMS FOR IMAGING DIAGNOSIS

KEY WORDS:

Semiconductor nanocrystals, gadolinium chelates, fluorescence, contrast agent, magnetic resonance imaging, photothermia.

PAGES: 123
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

Quantum Dots (QDs) are semiconductor nanocrystals with excellent optical properties due to their quantum  onfinement regime. They have found applications in various fields, such as biomedicine, particularly as  diagnostic and theranostic agents. For example, the association of fluorescent QDs with Gd3+ complexes, already used clinically, results in contrast agents (CAs) for magnetic resonance imaging (MRI), thus enabling their use in more than one imaging technique. The development of these nanoparticulate CAs helps to overcome the low sensitivity of MRI, enhancing the observable contrast in the images. In this work, multimodal systems were prepared using QDs with different compositions, conjugated with Gd3+ complexes derived from DOTA and folic acid (FA) molecules. Initially, CdTe QDs, well-known in the literature, were used to study the conjugation route with the complexes through the thiol-metal bond. Subsequently, the focus shifted to low-toxicity QDs, such as Ag2Se, AgInSe2 and Cu2-xSe. Followed by conjugation with FA to prepare multimodal nanosensors or theranostic agents. The optical characterization of the developed systems indicate that the conjugation did not impair the optical properties of the nanocrystals and, in some cases, reduced surface defects. From the relaxometric characterizations, it was observed that the systems showed promising results, increasing the r1 by up to 2.5 times compared to commercial DOTA, indicating that the preparation method was efficient in associating QDs with Gd3+ complexes. The results obtained so far demonstrate the potential of the prepared systems based on silver QDs to be used as CAs for MRI and optical imaging. Furthermore, the systems with Cu2-xSe QDs have shown potential as CAs for MRI and photothermal agents for cancer treatment.

COMMITTEE MEMBERS:
Presidente - 2330165 - MARIA GORETI CARVALHO PEREIRA
Interno - 2215007 - FERNANDO HALLWASS
Interno - 1354207 - SEVERINO ALVES JUNIOR
Externo ao Programa - 3340257 - DENYS EWERTON DA SILVA SANTOS - UFPEExterna ao Programa - 1995320 - LAIS ARAUJO SOUZA - UFPE