Banca de DEFESA: ELISÂNGELA DA COSTA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ELISÂNGELA DA COSTA SILVA
DATE: 27/10/2023
TIME: 14:00
LOCAL: Sala Carl Peter von Dietrich
TITLE:

TOXICITY ANALYSIS OF THE BIOMATERIAL HYDROXYAPATITE FUNCTIONALIZED WITH STRONTIUMION

(Sr-HA) IN ZEBRAFISH (Danio rerio)

KEY WORDS:

 

Nanostructured biomaterials, ionic substitution, synthesis temperature, embryonicbiosafety.

PAGES: 67
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

 

Hydroxyapatite (HA) is an essential inorganic component found in human bone tissue, and its compatibility with biological systems makesitwidelyapplicableinvariousbiomedicalfields.Theabilityto incorporate different ions into the HA structure allows the modification of its properties, making them more similar to those of bone tissue itself. One of these ions that can be incorporated is strontium, known for its ability to stimulate osteogenic activity. However, the biological effects of strontium-functionalized HA nanoparticles(SrHA)arenotyetcompletelyunderstood.Toaddress this gap, an embryotoxicity study was performed using zebrafish (Danio rerio), following OECD 236 guidelines. Zebrafish embryos were exposed to microspheres containing synthesized nSrHA nanoparticles at 5 °C and 90 °C for 120 hours. The mortality rate, development parameters, and production of reactive oxygen species (ROS) were evaluated during the test. At 168 hours post fertilization (hpf), behavioral parameters were assessed through motor responses and anxiety-like behavior to verify whether the biomaterialscausedneurotoxiceffects.Theresultsrevealedthatthe survival rate decreased in the SrHA group synthesized at 5 °C, and there was an increase in ROS production in this group. However, none of the biomaterials caused morphological changes that would suggest toxicity during larval development. Furthermore,behavioral tests showed no significant differences in any experimental groups, suggesting that exposure to the tested biomaterials did not have neurotoxic effects. These findings provide valuable information on the safety of HA-based nanostructured biomaterials and highlight theirpromisingapplicabilityinbonetissuerepair.Withtheincreasing use of hydroxyapatite-based biomaterials, investigations into the safety of these materials areessential.

COMMITTEE MEMBERS:
Presidente - 1199127 - SILVIA REGINA BATISTUZZO DE MEDEIROS
Interna - 1720860 - VANESSA DE PAULA SOARES RACHETTI
Externo à Instituição - CÉSAR KOPPE GRISÓLIA - UnB