Banca de QUALIFICAÇÃO: GABRIELA MARQUES DE ALBUQUERQUE

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : GABRIELA MARQUES DE ALBUQUERQUE
DATE: 23/09/2022
LOCAL: Remoto
TITLE:

DEVELOPMENT OF MULTIMODAL OPTICAL-PARAMAGNETIC NANOPLATFORMS FOR IMAGING DIAGNOSIS

KEY WORDS:

Semiconductor nanocrystals, paramagnetic chelates, fluorescence, contrast agent.

PAGES: 126
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUMMARY:

Quantum Dots (QDs) are semiconductor nanocrystals with excellent optical properties due their quantum confinement regime. They have found application in several areas, such as biomedicine, namely in the development of nanoparticulate contrast agents (CAs). In these systems, QDs are conjugated to Gd3+ complexes already used clinically as CAs for magnetic resonance imaging (MRI), thus being able to be used in more than one technique. This association suppresses the limitations of MRI, which despite being one of the main diagnostic imaging techniques and shows several advantages over other diagnostic methods, sometimes needs to increase the contrast observable in the image. In this work, bimodal systems were prepared using QDs of CdTe and AgInSe2, conjugated to complexes derived from DOTA. Cadmium-based QDs, whose properties are well known, were used to study the conjugation route with the complexes, which was carried out by thiol-metal bonding. From the positive results of these bimodal systems, the switch to a low toxicity QD, AgInSe2, was studied. Data obtained in the optical characterization of bimodal systems developed with both QDs, indicate that the conjugation does not affect the optical properties of the nanocrystals and, in some cases, can reduce surface defects. From the relaxometric characterizations, it was observed that both systems with CdTe and AgInSe2, showed promising results, increasing the r1 at least 5 and 1.5 times, respectively, with respect to commercial DOTA, indicating that its method of preparation was efficient in the association of QDs and Gd3+ complexes. The results obtained so far show the potential of systems prepared to be used as bimodal CAs. Thus, it is intended to continue the work by associating a biomolecule (folic acid) to these systems, making them multimodal and making it possible to carry out a specific cellular labeling.

BANKING MEMBERS:
Presidente - 2215007 - FERNANDO HALLWASS
Externa à Instituição - ANDREIA GERNISKI MACEDO - UTFPR
Externo à Instituição - CARLOS FREDERICO DE GUSMÃO CAMPOS GERALDES - UC